Content:

GI – Geosciences Instrumentation & Data Systems

GI1.1 – Open session on geoscience instrumentation and methods

EGU2020-4991 | Displays | GI1.1

Polarisation Based Interferometric Optical Fibre Geophone Sensor Designed for High Resolution Seismic Detection

James Jena, Shukree Wassin, Lucian Bezuidenhout, Moctar Doucouré, and Tim Gibbon

Geophones are essential for monitoring seismic activity to study the structure of the earth for ground surveys, mineral exploration and early warning detection of geo-hazards. Traditional electromagnetic based geophones are fairly effective in detecting micro-seismic activity and ambient signals. Their induction based mass-spring sensing mechanism can however be somewhat performance limiting. Limitations include reduced frequency response, resolution and recovery times between successive activities. This ultimately impacts the sensitivity and performance of the device. In this paper, we present a novel optical fiber geophone sensor that addresses these issues through superior sensitivity, performance and ease of deployment. Our optical fiber geophone is polarization based, single ended and operates on a Michelson interferometric principle. Tests were performed to compare the performance of our optical fibre geophone to that of a commercial electromagnetic geophone. Vibrations of varying magnitude were remotely generated at 1.065 m from both devices. Sensor signal responses to disturbances of energy lower than 1.1 mJ were plotted and analysed. Observed traces from the sensor responses were compared, showing that the fiber geophone has significantly shorter response and recovery times. As a result, the resolution between rapidly succeeding signals is considerably greater for the optical fiber geophone. Sensitivity plots of the amplitude response to the vibration energy gave a scatter of points depicting a higher degree of precision and accuracy for the fiber geophone. Response slopes of 11.70 a.u/mJ and 10.31 a.u/mJ respectively were obtained for the sensitivity of the optical fiber geophone versus the electromagnetic geophone. While the typical spurious frequency is close to 150 Hz for the traditional geophone, the bandwidth of the optical fiber geophone is an order of magnitude greater.

Keywords- Geophone, Optical fibre, Polarisation, Michelson Interferometer

How to cite: Jena, J., Wassin, S., Bezuidenhout, L., Doucouré, M., and Gibbon, T.: Polarisation Based Interferometric Optical Fibre Geophone Sensor Designed for High Resolution Seismic Detection, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4991, https://doi.org/10.5194/egusphere-egu2020-4991, 2020.

The chemical, mineralogical and textural investigation of drill cores demands objective and repeatable information unaffected by the human bias to be able to correlate significant features across drillcores. Imaging Laser induced Breakdown Spektroscopy (LIBS) can be applied to large scales at high spatial resolution in relatively short times to obtain detailed chemical, mineralogical and textural information with a minimum of sample preparation. The application of the Spectral Angle Mapper (SAM) algorithm for supervised classification of the LIBS hyperspectral data cubes provides a relatively fast, but easy to handle tool to visualize and quantify variations in the chemical, mineralogical composition of complex ores from the sub-millimetre to the metre scale. The information derived offers novel and barely investigated interpretation opportunities in a very detailed manner which directly can be used for exploration purposes. The investigated Merensky Reef is about 1 m thick. It consists of pegmatoidal pyroxenite framed by the lower and upper thin chromitite seams. The Merensky Reef is one major ore body out of three for platinum-group elements (PGE) within the Bushveld Igneous Complex which is the world’s largest known layered intrusion and largest PGE resource on Earth   Detailed LIBS-based imaging measurements with 200µm spotsize were accompanied by space-resolved reference measurements based on SEM/MLA (4µm) and µ-EDXRF (20µm), as well as bulk chemical analyses for multiple core slices. The SAM algorithm was applied for classification of hyperspectral LIBS images as being sensitive for differences in mineral chemistry. Focus was put on the pre-processing of LIBS spectra prior to SAM classification, on the development of the spectral library, and on the validation of the classified data. The SAM classification algorithm, which is solely based on ratios between spectral intensities, was found insensitive to normal shot-to-shot plasma variations and to chemically induced matrix effects. However, the algorithm may become inaccurate at low signal to noise ratios, at the border between different mineral grains (mixed spectra), or when classifying chemically similar phases such as pyrite and pyrrhotite. The extent of mixed spectra depends both on the size of the mineral grains as well as on the spot size of the LIBS laser. The SAM algorithm was successfully applied for classification of several base metal sulphides, rock-forming minerals, accessory minerals, as well as several mixed phases representing the main borders between different mineral grains. The obtained classified LIBS image images the spatial distribution of the different phases, which corresponds very well to the reference measurements based on highly space-resolved  EDXRF and SEM/MLA mineral distribution maps. The investigated core piece highlights the extremely heterogeneous distribution of e.g. the sulphide phases. The LIBS-SAM classification image was used to estimate metal concentrations based on point counting. The applicability has been explored for Cu, Ni, S, and Cr. This approach, when applied on sufficiently large surfaces, enables quantification of well-defined mineral phases, as well as the possible detection of trace elements (e.g. Pt, Pd) that occur in very small nuggets.

How to cite: Rammlmair, D. and Meima, J.: Quantitative mineralogy of chromite ore based on imaging Laser Induced Breakdown Spectroscopy and Spectral Angle Mapper Classification Algorithm, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19373, https://doi.org/10.5194/egusphere-egu2020-19373, 2020.

EGU2020-1503 | Displays | GI1.1

Monitoring African Bush Elephants with the OSOP Raspberry Shake and Boom

Oliver Lamb, Michael Shore, Jonathan Lees, and Stephen Lee

In terms of terrestrial animal communication, elephants are especially noteworthy because they have been documented to produce some of the loudest sounds at frequencies between 10-35 Hz. Their vocalisations, or ‘rumbles’, with fundamental frequencies in the infrasonic range (≤ 20 Hz) can have amplitudes as high as 117 dB. Here we present our efforts to evaluate the performance of the Raspberry Shake and Boom, a low-cost seismic and acoustic sensor, for identifying and monitoring the movements of African Bush Elephants (Loxodonta africana). The test area was the Adventures with Elephants elephant reserve in South Africa which includes a herd of 7 elephants (3 females, 2 males, and 2 juveniles). Within the reserve we deployed a local network of 5 Raspberry Shake and Boom units in October 2019 in order to record seismo-acoustic waves generated by the herd. The network also included other seismic and acoustic sensors of different sensitivities which were used to assess the performance Raspberry Shake and Boom units. We show that the Raspberry Shake and Boom units performed well during the deployment, with clear recordings of elephant movement and rumbles. The acoustic data also suggests that we may be able to discriminate between individual elephants due to the distinct frequencies of their rumbles. This presentation will provide general information on the potential use of low-cost sensor units for the purpose of unobtrusively monitoring vulnerable wildlife such as elephants.

How to cite: Lamb, O., Shore, M., Lees, J., and Lee, S.: Monitoring African Bush Elephants with the OSOP Raspberry Shake and Boom, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1503, https://doi.org/10.5194/egusphere-egu2020-1503, 2020.

EGU2020-7426 | Displays | GI1.1 | Highlight | Christiaan Huygens Medal Lecture

Multi-length probes in GPR and TDR data

Raffaele Persico

I will expose some possibilities regarding the use of metallic probes of different lengths in GPR and TDR prospecting. With regard to GPR, multi-length probes are dipole-like antennas whose length can be changed by means of switches. The switches can be implemented with PIN diodes, and can act as electronic “knifes”. Therefore, they allow to cut (switched off) or prolong (switched on) the branches of a couple of antennas, and this allows to have more couples of equivalent antennas making use of a unique physical couple of antennas. This allows to contain the size of the system. In particular, a reconfigurable prototypal stepped frequency GPR system was developed within the project AITECH (http://www.aitechnet.com/ibam.html)  and was tested in several cases histories  [1-3]. Within this reconfigurable GPR, it is also possible to reconfigure vs. the frequency the integration times of the harmonic tones constituting the radiated signal. This feature allows to reject external electromagnetic interferences without filtering the spectrum of the received signal [4] and without increasing the radiated power.

With regard to TDR measurements, a multi-length probe consists of a TDR device where the rods (in multi-wire version) or the length of internal and external conductor (in coaxial version) can be changed. This can be useful for the measurements of electromagnetic characteristics of a material under test (MUT), in particular its dielectric permittivity and magnetic permeability, both meant in general as complex quantities. Multi-length TDR measurements allow to acquire independent information on the MUT even at single frequency, and this can be of interest in the case of dispersive materials [5-6].

Acknowledgements

I collaborated with several colleagues about the above issues. To list of them would be long, so I will just mention their affiliations: Florence Engineering srl, University of Florence, IDSGeoradar srl, 3d-radar Ltd, Institute for Archaeological and Monumental Heritage IBAM-CNR, University of Bari, University of Malta. Finally, a particular mention is deserved for the Cost Action TU1208.

References

[1] R. Persico, M. Ciminale, L. Matera, A new reconfigurable stepped frequency GPR system, possibilities and issues; applications to two different Cultural Heritage Resources, Near Surface Geophysics, 12, 793-801, 2014.

[2] L. Matera, M. Noviello, M. Ciminale, R. Persico, Integration of multisensor data: an experiment in the archaeological park of Egnazia (Apulia, Southern Italy), Near Surface Geophysics, 13, 613-621, 2015.

[3] R. Persico, S. D'Amico, L. Matera, E. Colica, C. De, Giorgio, A. Alescio, C. Sammut and P. Galea, P. (2019), GPR Investigations at St John's Co‐Cathedral in Valletta, Near Surface Geophysics, 17, 213-229, 2019.

[4] R. Persico, D. Dei, F. Parrini, L. Matera, Mitigation of narrow band interferences by means of a reconfigurable stepped frequency GPR system, Radio Science, 51, 2016.

[5] R. Persico, M. Pieraccini, Measurement of dielectric and magnetic properties of Materials by means of a TDR probe, Near Surface Geophysics, 16,1-9, 2018.

[6] R. Persico, I. Farhat, L. Farrugia, S. d’Amico, C. Sammut, An innovative use of TDR probes: First numerical validations with a coaxial cable, Journal of Environmental & Engineering Geophysics, 23, 437-442, 2018.

How to cite: Persico, R.: Multi-length probes in GPR and TDR data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7426, https://doi.org/10.5194/egusphere-egu2020-7426, 2020.

EGU2020-7227 | Displays | GI1.1

Induction Magnetometer transported by UAV for power lines monitoring

Valery Korepanov, Vira Pronenko, Fedir Dudkin, and Andrii Prystai

Assessment of a power lines condition is an important task for all countries. It includes GPS mapping of the: 1) wire breaks; 2) places of the increased current leakage, for example corona detection; 3) degree of wires sagging between power line towers; 4) location and conditions of the power line towers; 5) vegetation encroachment along a power line corridor.  Considering that power line currents, including leakage currents, create strong magnetic field, use of magnetometers in the range from DC to sound frequencies for the solution of tasks 1-4 is highly prospective. At the same time, it is possible the control of the vegetation critical proximity to a power line adjacent zone by the increased leakage current (threats of the increased leakage current or breakdown to a tree crown). Thus the task 5 also can be solved.

The goal of the present report is to introduce the new design of miniature low-weight three-component sensor for measurement of alternative vector magnetic field onboard UAV – induction magnetometer (IM) - with autonomous system including two-component tiltmeter and GPS antenna inside in order to obtain precise measurement timing, UAV coordinates and altitude during movement. These data are stored in the SD memory card. Construction details, tests results and technical specifications of this IM for are presented.

How to cite: Korepanov, V., Pronenko, V., Dudkin, F., and Prystai, A.: Induction Magnetometer transported by UAV for power lines monitoring, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7227, https://doi.org/10.5194/egusphere-egu2020-7227, 2020.

EGU2020-4885 | Displays | GI1.1

The attenuation of coda waves in the RIF area.

Oussama Arab, mimoun harnafi, Ibrahim ouchen, roumaissae azguet, younes El Fellah, and sebbani Jamal

This work is presenting the attenuation of coda waves in the Rif region. Using 15 broadband stations, we investigate the attenuation of coda waves utilizing the single backscattering model of aki and chouet. We collect 70 local earthquakes during 2014 for five laps time window 20, 30, 40, 50 and 60s. We computed the quality factors at different central frequencies band on which start from 1.5, 3.0, 6.0, 9.0, 12.0 and 18.0 Hz. For 40s window length, the Qc gives average value for the whole zone of about 128,51 for 1.5 Hz and 993,44 for 18 Hz band frequencies. We observed a clear dependency between the quality factor and the frequency. Also, we have found that this region is tectonic active comparing to previous studies around the world.

How to cite: Arab, O., harnafi, M., ouchen, I., azguet, R., El Fellah, Y., and Jamal, S.: The attenuation of coda waves in the RIF area., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4885, https://doi.org/10.5194/egusphere-egu2020-4885, 2020.

EGU2020-407 | Displays | GI1.1

Cost-effective recreational-grade single beam echosounder with side scan sonar system in imaging bubbly coastal submarine groundwater discharge

Mary Rose Gabuyo, Fernando Siringan, Keanu Jershon Sarmiento, and Paul Caesar Flores

Submarine groundwater discharge (SGD) is any direct flow of fluid across the seafloor, which forms bubbly or leaky springs and seeps from the intertidal zone to the deep sea. SGDs can significantly alter physico-chemical conditions of seepage zones. Identifying and mapping SGD is crucial to further recognize its influence in both marine and terrestrial ecosystems. However, mapping this phenomenon has been a continuing challenge, mainly due to the difficulty in its detection and quantification. This study explores the capability and applicability of an inexpensive, commercially available, recreational-grade combination of depth meter and side scan sonar system to image different types and identify point sources of coastal SGDs. Standard and systematic methodologies for efficient imaging and processing were established. The utility of the recreational-grade system was assessed and validated using a research-grade side scan sonar. SCUBA diving and CTD casting were conducted for ground-truthing and further characterization. Lower frequency sonars (83/200 kHz) showed more distinct acoustic signatures of discrete and dispersed bubbly SGDs, than the higher frequency system (455 kHz and 780 kHz research-grade unit). Sonar images showed that SGD plumes can be indicated by near seafloor to midwater cloud-like features. Spring-type SGDs tend to form cloud features with a funnel-shaped morphology. In sites where SGDs are dispersed, the acoustic signature is a curtain-like cloud, with higher bubble density in the upper water column. This is consistent with diver-based observation of increasing bubble sizes (<1 mm to ~30 mm) from point source to water surface. CTD casts indicate that the SGDs have recirculated seawater, with increasing temperature and salinity with depth. In the assessment of system and data processing requirements, and costing, a recreational-grade unit provides a good alternative for coastal SGD works.

How to cite: Gabuyo, M. R., Siringan, F., Sarmiento, K. J., and Flores, P. C.: Cost-effective recreational-grade single beam echosounder with side scan sonar system in imaging bubbly coastal submarine groundwater discharge, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-407, https://doi.org/10.5194/egusphere-egu2020-407, 2020.

EGU2020-21715 | Displays | GI1.1

Benchmark of multiple geophysics tools to study the voids in the upper levels of a decommissioned iron mine

Simon Bouteille, Adnand Bitri, Michel Dietz, and Julien Gance

Absorption muon imaging is a technique that can measure density variations underground down to a few hundred meters. Then, it can prove to be useful in a mining environment: to help assess the ore bodies volumes and/or to monitor the underground for natural hazards that can happen at the surface because of the mining exploitation. Here we report the result of an experiment designed to test the capabilities and resolution power of a cosmic muon measurement in a mining environment compared to other standard geophysics tools: gravimetry and seismic studies. It consists of three independent measurement of a subset of the decommissioned iron mine of May-sur-Orne (France). The first one was made using a 50x50cm² micromegas based muon telescope installed at the deepest non-submerged level (50m underground) during 3 months. The second one is a gravimetry survey of the surface area inside the muon telescope acceptance cone. And the third one is a study of refracted and reflected seismic waves along a single line above the muon telescope location. The investigation volume was chosen because of the presence of surface risks (neighborhood), the unknown of some uncharted volume and the presence of an ore storage volume of several meter cubed that was used during the mine exploitation and which filling state is unknown.

The data analysis showed that while muon tomography is able to detect the negative density anomaly of the storage volume, the gravimetry measurement is not sensible to it. However, the seismic study was able to detect the volume as well and its location and extension is compatible with the muon measurement.

How to cite: Bouteille, S., Bitri, A., Dietz, M., and Gance, J.: Benchmark of multiple geophysics tools to study the voids in the upper levels of a decommissioned iron mine, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21715, https://doi.org/10.5194/egusphere-egu2020-21715, 2020.

EGU2020-18524 | Displays | GI1.1

Building a perfomance protocol of a low cost seismograph

Markos Avlonitis, Spiridon Krokidis, Ioannis Vlachos, Vasileios Karakostas, and Anastasios Kostoglou

The low cost seismograph under study consists of low cost open source hardware and software microprocessor boards (Arduino Uno R3  and Raspberry Pi 3 B+ ), customized low noise design signal amplifiers, low power dissipation sophisticated power supply, two (2) kinds of earth ground shaking sensors a) Ceramic Accelerometer with cutoff frequency fc=0.15Hz and b) moving coil geophone with cutoff frequency fc=4.5Hz. The signals from the two sensors are amplified independently, while an active second order low-pass anti-alias filter and an 8th order active low-pass anti-alias filter have been used. Finally, a low-cost microprocessor board is responsible for digitizing the analog data from the amplified signal of the sensors with a frequency sampling rate of 345Hz. The aim of the present work is to design and test a systemic protocol in order to evaluate the performance of the proposed low cost seismograph for monitoring local to regional seismicity and micro seismicity. The proposed low-cost system was installed in an area of high seismic activity (Lefkada Island – Village Evgiros) and the recordings are transmitted to the database continuously from the day of its installation up today. Thus have create an amount of data for more than 280 days and all of those data have been stored to our database. Collocated with a high resolution 24 bits digitizer equipped with a broad band seismometer give us the opportunity to compare the recordings. To this end, a testing list of 15 local events has been created with different epicenters and magnitudes. For each event the recording signals have been analyzed in terms of a) power spectrum analysis, b) estimation of first arrival times of both P and S waves, c) signal amplitudes and d) earthquake duration. The choice of those specific measures was done in order to evaluate the performance of the low-cost seismograph in terms of certain seismic parameters such as magnitude, epicenter and source properties. Initial results in terms of the proposed protocol are also presented showing an adequate performance of the propose low cost seismograph.

 

Keywords:
low-cost instruments, Ionian islands, performance protocol

Acknowledgements
«Telemachus – Innovative Seismic Risk Management Operational System of the Ionian Islands» which is part of the Operational Program «Ionian Islands 2014-2020» and is co-financed by the European Regional Development Fund (ERDF) (National Strategic Reference Framework - NSRF 2014-20).

How to cite: Avlonitis, M., Krokidis, S., Vlachos, I., Karakostas, V., and Kostoglou, A.: Building a perfomance protocol of a low cost seismograph, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18524, https://doi.org/10.5194/egusphere-egu2020-18524, 2020.

EGU2020-19522 | Displays | GI1.1

Simplifying Instrument Pools: The Next Generation Family of Smart Instrumentation.

Sally Mohr, Marie Balon, Sofia Filippi, Neil Watkiss, and Phil Hill

As the community further expands their scope of study, pushing into different sub-disciplines and evermore challenging environments, the need for dynamic and highly adaptable systems grows. One of the challenges for instrument pool managers is finding a system that can cater for a wide range of possible use scenarios.

This is where traditional broadband, force-feedback sensors meet their limitations: with constrained frequency responses and sensitivities, they tend to target very narrow applications offering limited flexibility. When managing a pool of instruments, this translates into increasing pressure to acquire multiple units within different instrument ranges to meet the requirements for each specific application. This in turn leads to complex pool maintenance and may require operators to use unfamiliar instruments if their first choice is being used owing to a reduced number of instruments for each application within the pool.

Güralp’s 35 years’ experience in working with major national instrument pools revealed the necessity to develop flexible, easy-to use systems that could fit a wider scope of applications. This has led to a new, highly versatile smart sensor that supports extensive user configuration and ultra-wide tilt ranges.

The new sensor has a configurable long period corner allowing for rapid deployment in a range of environments: the 1s mode ensures the sensor settles quickly for rapid response purposes, and the 120s mode is ideally suited for long period observation.

The group of products that use this technology deliver high sensor reliability, sophisticated tools for ease of instrument and data management as well as industry standard data formats. The sensors have been integrated into various instruments: the Certimus for surface and shallow burial, the Radian for deeper postholes and boreholes, and the Fortimus for strong-motion applications.  The same philosophy also brought about Aquarius, an Ocean Bottom Seismometer that utilises the same sensor technology for the benefit of OBS pools.

This family of just four instruments covers the vast majority of seismic monitoring requirements. They represent Güralp’s solution to make instrument pool management easier and more affordable.

 

 

How to cite: Mohr, S., Balon, M., Filippi, S., Watkiss, N., and Hill, P.: Simplifying Instrument Pools: The Next Generation Family of Smart Instrumentation., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19522, https://doi.org/10.5194/egusphere-egu2020-19522, 2020.

Exploitation of super-critical water from deep geothermal resources can potentially give a 5-10 fold increase in the power output per well. Such an improvement represents a significant reduction in investment costs for deep geothermal energy projects, thus improving their competiveness.

In the previous European Horizon2020 DESCRAMBLE (Drilling in dEep, Super-CRitical AMBients of continental Europe) project it was demonstrated drilling of a deep geothermal well with super-critical conditions (>375°C, >220 bar) by extending an existing well in Larderello, Italy to a depth of around 4km. As state-of-the-art electronic logging tools could not operate reliably at these conditions, DESCRAMBLE developed and tested a novel pressure and temperature logging tool for these supercritical conditions. Target specification for the slickline operated tool was 8 hours logging operation time at 450°C/450 bar, limited by the critical temperature for the available battery technology used for the application. During testing in the supercritical well in Larderello, Italy in 2017, the tool recorded a maximum well temperature of 443.6°C.

The instrument developed in the DESCRAMBLE project, although being state-of-the-art in its performance, was costly and advanced in addition to having a larger outer diameter than desired in for example slim-well applications. Therefore, there is a need for a simpler, lower cost version of this tool with a smaller outer diameter.

The tool being developed, based on the H2020 DESCRAMBLE project, consists of off-the-shelf high temperature electronics, sensors and batteries shielded from the environment by a heat and pressure shield (Dewar). The target specification for the tool is 600°C/500Bar, with a shorter operational time than the DESCRAMBLE tool.

In this work, we describe the tool requirements and discuss the design choices made regarding mechanical parts, seals, electronics platform, sensors, and available battery technology. 3D CAD drawings and simulations of the thermal performance of the tool will be presented, as well as preliminary test results of the electronic platform combined with the sensors and batteries. Production and testing of the physical tool will not be within the scope of the project.

 

How to cite: Hamremoen Røed, M.: Development of a Low Cost Novel PT Logging Tool for High Temperature Operation (600°C), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21488, https://doi.org/10.5194/egusphere-egu2020-21488, 2020.

GI1.2 – COST Actions in geosciences: breakthrough ideas, research activities and results

EGU2020-22484 | Displays | GI1.2 | Highlight

Creating Impact through COST Action networks

Deniz Karaca

The European Cooperation in Science and Technology (COST) has a very important role in fostering the establishment of scientific excellence in many fields such as: Geoscience, Planetary and Environment. Over the years, COST Actions have contributed to European competitiveness through their many contributions to standardisation bodies, the small to medium enterprises originating from COST networks and the transfer of results to the European industry.

A series of COST Actions in the field of Meteorology developed global data transfer standards on the basis of infra-networks in collaboration with the World Meteorological Organization advantaging the competitiveness of the industrial participation. Such achievements include harmonisation of UV-index, developing operational programmes, services, networks and phenological responses to climate on a Pan-European Scale and were recognised by the Intergovernmental Panel on Climate Change.  European Centre for Medium-Range Weather Forecasts (ECMWF) is another good example as a result of an Action through its evolution to become an independent intergovernmental organisation with its own structure and headquarters supported by 34 states.

The key findings of COST networks not only contribute to the atmospheric drivers on the impacts of the global change but also increase the understanding of the function of marine ecosystems and its response to climate change. A number of Actions in the field of marine science have developed observing system to integrate the dynamic response of sea-level variations to combine effects of various natural drivers into multi-criteria tools by bringing together oceanographers and meteorologists. These developments urged for an integrated implementation of technology in sea-level monitoring, and for further international agreements on data storage and exchange.

A wide range of disciplines, evaluating the complex interactions between the oceans and the global change, geosciences, natural resources management, environmental monitoring, biogeochemical cycles,  ecology, hydrology, natural disasters, water cycle have well undertaken through COST Action networks. The results were published in high impact journals, guidelines were represented in position papers leading to new research projects on a global scale.  Participation in COST leads to significant results and follow-up in terms of number of proposals submitted for collaborative research in Horizon 2020, with a striking success rate of 33% (the Horizon 2020 average is at 12.2%). By enabling researchers and innovators from all career levels to network, COST connects complementary funding schemes, facilitating the entry of promising young talents into these schemes.

COST is committed to reinforcing its role as the leading networking instrument in the European Research Area (ERA), while creating even higher tangible impact on society.

How to cite: Karaca, D.: Creating Impact through COST Action networks, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22484, https://doi.org/10.5194/egusphere-egu2020-22484, 2020.

About 6 million years ago, the Mediterranean basin was the focus of one of the most extraordinary events in the recent geological history of the Earth: the so-called Messinian Salinity Crisis (MSC). MEDSALT aims to create a new flexible scientific network addressing the causes, timing, emplacement mechanisms, and consequences – at local and planetary scale – of the largest and most recent ‘salt giant’ on Earth: the Mediterranean Salt Giant (MSG). The MSG is a 1.5 km thick salt layer that was deposited on the bottom of deep Mediterranean basins about 5.5 million years ago, in late Miocene (Messinian), and is preserved beneath the deep ocean floor today. The origin of the Mediterranean salt giant is linked the Messinian Salinity Crisis. Research on the MSC has initiated one of the longest-living scientific controversies in Earth Science. Pioneering scientific drilling in 1970 induced some researchers to publish the theory of the ‘desiccation’ of the Mediterranean during the Messinian. In their view the Mediterranean Sea level dropped by 1–2 km and the basin was transformed into a huge hot, dry salt lake as a consequence of the tectonically-driven closure of the Atlantic gateway at the present-day Gibraltar strait.

This interpretation was successful not only among the scientific community, but also in public opinion. On one hand, the progress of scientific research provided additional evidence for the desiccation theory. On the other hand, researchers questioned the theory, providing alternative interpretations of the geological data, and theoretical arguments supporting a model of salt deposition from a deep brine, assuming a very limited sea level change. Controversial views also exist on the mechanisms that ended the MSC: was it a catastrophic flood of Atlantic waters from the re-opening of the Atlantic gateway, or a slow mixing with brackish water from the Black Sea area first before the re-establishment of the normal marine connection with the Atlantic Ocean? In order to trigger progress on the understanding of the MSC, a widespread international scientific community has promoted the largest coordinated research on the MSC since its discovery, clustered around scientific drilling. COST (European Cooperation in Science and Technology) was identified as the most appropriate tool, as COST Actions provide tools for networking, training, mobility and dissemination. The network has further promoted one Marie Skłodowska-Curie European Training Network (SALTGIANT) offering 15 PhD fellowships across Europe. New contacts have been activated with a variety of stakeholders, including governmental administrations, non-governmental organizations, the industry and, indirectly, society at large, demonstrating the importance that science and society renew a relationship of trust and confidence. In all, 200 scientists are working together – across disciplines such as geophysics, geology, biology, microbiology, and also social sciences – towards a common scientific goal: uncovering the Mediterranean salt giant.

How to cite: Camerlenghi, A. and Aloisi, V.: Uncovering the Mediterranean Salt Giant (MEDSALT) – Scientific Networking as Incubator of Cross- disciplinary Research in Earth Sciences, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3657, https://doi.org/10.5194/egusphere-egu2020-3657, 2020.

EGU2020-12910 | Displays | GI1.2

EU COST Action ES1404-HarmoSnow

Ali Nadir Arslan

The European Cooperation in Science and Technology (COST) promoted and funded the Action ES1404 called “A European network for a harmonized monitoring of snow for the benefit of climate change scenarios, hydrology, and numerical weather prediction,” or “HarmoSnow” (2014-2018). With 29 European COST countries and the international partners Andorra and Taiwan (https://www.cost.eu/actions/ES1404/) HarmoSnow coordinated efforts towards harmonized snow data processing and handling practices by promoting new observing strategies. The vision was to connect different communities, facilitating data transfer, upgrading and enlarging knowledge through networking and linking them to activities in international agencies and global networks (www.harmosnow.eu).

The main aim of HarmoSnow was to enhance the capability of the research community and operational services to provide and exploit quality-assured and comparable observation data on the variability of the state and extent of snow. The overall objectives were (1) Establish a European-wide science network on snow measurements for their optimum use with interactions across disciplines and expertise, (2) Assess and harmonise practices, standards and retrieval algorithms applied to snow measurements, (3) Develop a rationale and long term strategy for snow measurements and their dissemination, (4) Advance snow data assimilation in NWP and hydrological models, (5) Establish a validation strategy for climate, NWP and hydrological models against snow observations and foster its implementation, (6) Training of a new generation of scientists on snow science and measuring techniques with a broader and more holistic perspective.

We will present outcomes from the HarmoSnow activities and discuss how to move forward.

How to cite: Arslan, A. N.: EU COST Action ES1404-HarmoSnow, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12910, https://doi.org/10.5194/egusphere-egu2020-12910, 2020.

EGU2020-22084 | Displays | GI1.2

Results of the cyberparks cost action tu 1306

Eva Savina Malinverni, Roberto Pierdicca, Carlos Smaniotto Costa, Alfonso Bahillo Martinez, and Ernesto Marcheggiani

The present abstract is aimed at describing the activities and results about Cyberparks COST Action TU 1306. The purpose of the action was to increase the knowledge about the existing relationship between Information and Communication Technologies (ICT) and Public Spaces, supported by strategies to improve their use and attractiveness. In such scenario, the project developed several case studies to develop best practices and digital tools able to collect information directly from the users, in real time. Indeed, sensors where installed in Public Spaces, as well as mobile applications that allowed to provide user’s with contextual information and Location Based Services and, at the same time, to collect the so called User Generated Data. In such way, people experiencing a certain place could enhance their knowledge and administration (or public authorities) could understand how user’s exploit it. Moreover, the project stimulated the use of new technologies like Augmented Reality as an additional service, useful to discover the surrounding and enhance the sense of presence of the users. CyberParks allowed to uncover opportunity and risks related to the use of ICTs via the appreciation, design and usage of public spaces. It exploited the benefits of interweaving a green experience with digital engagement via sharing knowledge, experiences and ideas, and analyzing public spaces.

The methodology developed can be of great interest especially for urban planning purposes; in fact, the pen-and-pencil approach for redesigning and rethinking a place can be partially replaced by a data driven approach, that can be more objective and reliable.

More than 50 scientific papers were published and very fruitful Short Term scientific missions. A great number of data was collected from real scenario, demonstrating the effectiveness of the methods adopted to conduct researches and experiment. Another noteworthy output of the project is the exploitation of a multidisciplinary group. In fact, the amalgamation of researchers coming from different scientific disciplines allowed to enhance the knowledge and strength cooperation between humanistic disciplines and digital sciences.

How to cite: Malinverni, E. S., Pierdicca, R., Smaniotto Costa, C., Bahillo Martinez, A., and Marcheggiani, E.: Results of the cyberparks cost action tu 1306, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22084, https://doi.org/10.5194/egusphere-egu2020-22084, 2020.

Underground4value (COST Action CA18110) is a four years’ project (2019-2023) establishing an expert network from twenty-nine countries, with the objective of promoting balanced and sustainable approaches for the conservation and promotion of underground built heritage (UBH). Every year, four underground sites and their local communities become places for experimenting studies, new policies, and participatory approaches. During the first year (April 2019 - March 2020), the sites of Naples (Italy), La Union (Murcia, Spain), Postojna (Slovenia) and Göreme (Cappadocia, Turkey) have been selected. The originality of the approach is that it is geared towards assisting local communities’ decision-making with cultural, scientific and technical knowledge of the underground built heritage, from many different perspectives: archaeology, geo-technics, history, urban planning, cultural anthropology, economics, architecture, cultural tourism, ecology.

The Living Lab approach is used to organise fieldwork, spending time on each site with a mix of participants (international scientists and local practitioners). The idea is to identify and explore social innovations models for empowering local communities and making them part of the UBH promotion process. Collected information is then the basis for developing new research and training, which remain open and accessible. Knowledge transfer is secured by several dedicated tasks, including a Training School, held in last February in Naples, where the trainees have morning learning sessions and afternoon research activities on specific topics occurred in the living labs’ activities.

How to cite: Pace, G.: COST Action Underground4value: Living Labs for the Underground Built Heritage valorisation , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10408, https://doi.org/10.5194/egusphere-egu2020-10408, 2020.

EGU2020-21733 * | Displays | GI1.2 | Highlight

The COST action CA17133 "Circular city"

Natasa Atanasova and Guenter Langergraber

Resource depletion, climate change and degradation of ecosystems are challenges faced by cities worldwide and will increase if cities do not adapt. In order to tackle those challenges, it is necessary to transform our cities into sustainable systems using a holistic approach. One element in achieving this transition is the implementation of nature-based solutions (NBS). They can provide a range of ecosystem services beneficial for the urban biosphere such as regulation of micro-climates, flood prevention, water treatment, food provision and more. However, most NBS are implemented serving only one single purpose. Adopting the concept of circular economy by combining different types of services and returning resources to the city, would increase the benefits gained for urban areas.

The COST Action CA17133 "Implementing nature-based solutions for creating a resourceful circular city" aims to establish a network testing the hypothesis that a circular flow system that implements NBS for managing nutrients and resources within the urban biosphere will lead to a resilient, sustainable and healthy urban environment.

To tackle this challenge the Action comprises five working groups (WGs):

  • WG1: Built environment
  • WG2: Sustainable urban water utilisation
  • WG3: Resource recovery
  • WG4: Urban Farming
  • WG5: Transformation tools

The network of researches, companies and stakeholders from more than 40 countries spread over whole Europe brings together a large diversity of disciplines and is therefore well equipped taking holistic approach on embedding NBS within circular economy. In the presentation we will present the first results already achieved and the future plans of the Action.

How to cite: Atanasova, N. and Langergraber, G.: The COST action CA17133 "Circular city", EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21733, https://doi.org/10.5194/egusphere-egu2020-21733, 2020.

EGU2020-22165 | Displays | GI1.2

Ambient seismic noise suppression in COST action G2Net

Velimir Ilić, Alessandro Bertolini, Fabio Bonsignorio, Dario Jozinović, Tomasz Bulik, Ivan Štajduhar, Iulian Secrieru, and Soumen Koley

The analysis of low-frequency gravitational waves (GW) data is a crucial mission of GW science and the performance of Earth-based GW detectors is largely influenced by ability of combating the low-frequency ambient seismic noise and other seismic influences. This tasks require multidisciplinary research in the fields of seismic sensing, signal processing, robotics, machine learning and mathematical modeling.

In practice, this kind of research is conducted by large teams of researchers with different expertise, so that project management emerges as an important real life challenge in the projects for acquisition, processing and interpretation of seismic data from GW detector site. A prominent example that successfully deals with this aspect could be observed in the COST Action G2Net (CA17137 - A network for Gravitational Waves, Geophysics and Machine Learning) and its seismic research group, which counts more than 30 members. 

In this talk we will review the structure of the group, present the goals and recent activities of the group, and present new methods for combating the seismic influences at GW detector site that will be developed and applied within this collaboration.

 

This publication is based upon work from CA17137 - A network for Gravitational Waves, Geophysics and Machine Learning, supported by COST (European Cooperation in Science and Technology).

How to cite: Ilić, V., Bertolini, A., Bonsignorio, F., Jozinović, D., Bulik, T., Štajduhar, I., Secrieru, I., and Koley, S.: Ambient seismic noise suppression in COST action G2Net, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22165, https://doi.org/10.5194/egusphere-egu2020-22165, 2020.

EGU2020-19560 | Displays | GI1.2

Soil Moisture Retrievals from Unmanned Aerial Systems (UAS)

ruodan zhuang, Salvatore Manfreda, Yijian Zeng, Zhongbo Su, Nunzio Romano, Eyal Ben Dor, Antonino Maltese, Fulvio Capodici, Antonio Paruta, Paolo Nasta, Nicolas Francos, Giuseppe Ciraolo, Brigitta Szabó, János Mészáros, and George P. Petropoulos

Quantification of the spatial and temporal behavior of soil moisture is vital for understanding water availability in agriculture, ecosystems research, river basin hydrology and water resources management. Unmanned Aerial Systems (UAS) offer a great potential in monitoring this parameter at sub-meter level and at relatively low cost. The standardization of operational procedures for soil moisture monitoring with UAS can be beneficial to understanding and quantify the quality of retrieved soil moisture (e.g., from different platforms and sensors).

In this study, soil moisture retrieved from UAS using different retrieval algorithms was compared to collocated ground measurements. The thermal inertia model builds upon the dependence of the thermal diffusion on soil moisture. The soil thermal inertia is quantified by processing visible and near-infrared (VIS-NIR) and thermal infrared (TIR) images, acquired at two different times of a day. The temperature–vegetation trapezoidal model is also used to map soil moisture over vegetated pixels. This trapezoidal model depicts the soil moisture dependence of the surface energy balance. The comparison of the two algorithms helps define a preliminary standard procedure for retrieving soil moisture with UAS.

As a case study, a typical cropland area with olive orchard, cherry and walnut trees in the region of Monteforte Cilento (Italy, Salerno) is used, where optical and thermal images and in situ data were simultaneously acquired. In the Alento observatory, long-term studies on vadose zone hydrology have been conducting across a range of spatial scales. Our findings provide an important contribution towards improving our knowledge on evaluating the ability of UAS to map soil moisture, in support of sustainable natural resources management and climate change studies.

This research is a part of EU COST-Action “HARMONIOUS: Harmonization of UAS techniques for agricultural and natural ecosystems monitoring”.

Keywords: soil moisture, Unmanned Aerial Systems, thermal inertia, HARMONIOUS

How to cite: zhuang, R., Manfreda, S., Zeng, Y., Su, Z., Romano, N., Ben Dor, E., Maltese, A., Capodici, F., Paruta, A., Nasta, P., Francos, N., Ciraolo, G., Szabó, B., Mészáros, J., and Petropoulos, G. P.: Soil Moisture Retrievals from Unmanned Aerial Systems (UAS), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19560, https://doi.org/10.5194/egusphere-egu2020-19560, 2020.

EGU2020-5122 * | Displays | GI1.2 | Highlight

Accelerating Global Science on Tsunami Hazard and Risk Analysis (AGITHAR)

Joern Behrens, Inigo Aniel-Quiroga, Sebastiano D'Amico, Frederic Dias, Ira Didenkulova, Serge Guillas, Stefano Lorito, Finn Lovholt, Jorge Macias, Shane Murphy, Ocal Necmioglu, Rachid Omira, Simone Roedder, and Mathilde Sorensen

Recent tsunami disasters revealed severe gaps between the anticipated level of hazard and the true extent of the event, with resulting loss of life and property. The severe consequences were underestimated in part due to the lack of rigorous and accepted hazard analysis methods and large uncertainty in forecasting the tsunami source mechanism and strength. Uncertainty and underestimation of the hazard and risk resulted in insufficient preparedness measures. While there is no absolute protection against disasters of the scale of mega tsunamis, a more accurate analysis of the potential risk can help to minimize losses from tsunami.
After the major events in 2004 and 2011 many new initiatives originated novel methods for tsunami hazard and risk analysis. However, rigorous performance assessment and evaluation – with respect to guiding principles in tsunami hazard and risk analysis – has not been conducted. In particular, comprehensive uncertainty assessments and related standards are required in order to implement more robust and reliable hazard analysis strategies and, ultimately, better mitigate tsunami impact. This is the core challenge of the proposed COST Action Accelerating Global science In Tsunami HAzard and Risk analysis (AGITHAR).
In our presentation we will demonstrate first results of the Action, assessing research gaps, open questions, and a very coarse roadmap for future research.

How to cite: Behrens, J., Aniel-Quiroga, I., D'Amico, S., Dias, F., Didenkulova, I., Guillas, S., Lorito, S., Lovholt, F., Macias, J., Murphy, S., Necmioglu, O., Omira, R., Roedder, S., and Sorensen, M.: Accelerating Global Science on Tsunami Hazard and Risk Analysis (AGITHAR), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5122, https://doi.org/10.5194/egusphere-egu2020-5122, 2020.

EGU2020-10625 * | Displays | GI1.2 | Highlight

BOTTOMS-UP: Biodiversity of Temperate Forest Taxa to Orient Management Sustainability by Unifying Perspectives

Murat Sarginci, Péter Ódor, Inken Doerfler, Thomas Nagel, Yoan Paillet, Tommaso Sitzia, Flóra Tinya, Admir Avdagić, and Julie Ballweg and the COST Action CA18207

Forests provide essential economic, social, cultural and environmental services. To be able to maintain the provision of these services, sustainable forest management (SFM) is a vital obligation. The maintenance of biodiversity, ranging from gene to ecosystem levels, is essential for functions and associated services, and it is one of the most important criterion for assessing sustainability in the Pan-European region. 
Currently, the majority of SFM Criteria and Indicators focuses on attributes relative to tree species or to the whole forest. With reference to biodiversity conservation, this means that the collected information cannot fully assess whether forests are being managed sustainably. To understand the drivers of forest biodiversity and drive sustainable management, several taxonomic groups should be investigated, since they may respond differently to the same environmental pressures. However, up to now, broad multi-taxonomic analyses were mainly performed through reviews and meta-analyses which limit our holistic understanding on the effects of forest management on different facets of biodiversity. Recently, several research institutions took up the challenge of multi-taxonomic field sampling. These local efforts, however, have limited extrapolation power to infer trends at the European scale. It is high time to share, standardize and use existing multi-taxon data through a common platform to inform sound management and political decisions. Biodiversity indicators have also some potential to be used in evaluation of impact of forest management on soils and surface waters in terms of naturalness, degradation and reclamation.
We present the COST Action CA18207 “Biodiversity of Temperate forest Taxa Orienting Management Sustainability by Unifying Perspectives” (Bottoms-Up). It will gather the most comprehensive knowledge of European multitaxonomic forest biodiversity through the synergy of research groups that collected data locally in more than 2200 sampling units across approximately 300 sites covering nine different European forest types. For each sampling unit, information will be available on at least three taxonomic groups (vascular plants, fungi, lichens, birds and saproxylic beetles being the most represented) and on live stand structure and deadwood. Multi-taxon biodiversity will be associated with: (i) information on forest management based on observational studies at the coarse scale, and (ii) structural data deriving from forest manipulation experiments at the fine scale. 

Specific objectives are:
• Developing a standardized platform of multi-taxon data;
• Establishing a network of forest sites with baseline information for future monitoring;
• Designing shared protocols for multi-taxon sampling;
• Assessing the relationships between multi-taxon biodiversity, structure and management;
• Creating a coordinated network of forest manipulation experiments;
• Evaluating indicators and thresholds of sustainability directly tested on biodiversity;
• Developing management guidelines defining sustainable management to be applied in forest certification and within protected areas.

The Action involves about 80 researchers and stakeholders from 29 countries and represents an outstanding opportunity to develop a strong network of collaboration for standardized broad-scale multitaxon studies in Europe.

Keywords:  Multi-taxon, Pan-European region, Sustainable Forest Management. 

 

How to cite: Sarginci, M., Ódor, P., Doerfler, I., Nagel, T., Paillet, Y., Sitzia, T., Tinya, F., Avdagić, A., and Ballweg, J. and the COST Action CA18207: BOTTOMS-UP: Biodiversity of Temperate Forest Taxa to Orient Management Sustainability by Unifying Perspectives, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10625, https://doi.org/10.5194/egusphere-egu2020-10625, 2020.

EGU2020-14370 * | Displays | GI1.2 | Highlight

inDust: International Network to encourage the use of monitoring and forecasting DUST products

Sara Basart and Slodoban Nickovic and the inDust Core Group

Sand and Dust Storms (SDS) are extreme meteorological phenomena that generate significant amounts of airborne mineral dust particles. SDS plays a significant role in different aspects of weather, climate and atmospheric chemistry. Also, SDS represents a severe hazard for life, health, property, environment and economy, which is aligned with several Sustainable Developed Goal (SDG) targets established by the United Nations (UN). Understanding, managing, and mitigating SDS risks and effects requires fundamental and cross-disciplinary knowledge.

Over the last few years, there is an increasing need for SDS accurate information and predictions to support early warning systems, and preparedness and mitigation plans in addition to growing interest from diverse stakeholders, such as solar energy plant managers, health professionals, aviation and policymakers from environmental and health public sectors. Current attempts to transfer tailored products to end-users are not coordinated, and the same technological and social obstacles are tackled individually by all different groups, a process that makes the use of data slow and expensive.

The EU-funded COST Action inDust (www.cost-indust.eu, CA16202) has an overall objective to establish a network involving research institutions, service providers and potential end-users of information on airborne dust that can assist the diverse socio-economic sectors affected by the presence of high concentrations of atmospheric dust. In line with this main objective, the network is being worked on the identification and engagement of representatives of dust affected socio-economic sectors (targeting on air quality and health, aviation and solar energy) from different countries in Europe but also in North Africa and the Middle East. Moreover, the participation of South African, American and importantly Asian partners brings the possibility of extending the application of the developed products, protocols and tools well beyond the European borders, including areas like Asian regions where dust particles play a significant role in the air quality and meteorological processes.

The primary outcomes of the network are the identification of the needs of the various and new dust-related products and services able to satisfy these needs. As a result, the network has been working on a dust catalogue which includes an overview of (ground-based and satellite) observations and model products.

How to cite: Basart, S. and Nickovic, S. and the inDust Core Group: inDust: International Network to encourage the use of monitoring and forecasting DUST products, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14370, https://doi.org/10.5194/egusphere-egu2020-14370, 2020.

EGU2020-20728 | Displays | GI1.2

Profiling the Atmospheric Boundary Layer at European Scale - COST Action

Kreso Pandzic and Tanja Likso

A three-dimensional spatial analysis of atmosphere, including its boundary layer, has become possible after upper air vertical atmospheric observation started. Mountain observatories, as e.g. at the Sonnblick Observatory in Austrian Alpine, which operates since 1866, belong to a group of such observation. During 18-th and 19-th century upper air observations have been made by balloons equipped with meteorological instruments. The first such observation was done at Glasgow in 1749. The first radiosounding vertical profile observation was done in 1927. At the end of 1940-s an operative network of radiosounding stations has been started to use for construction of upper air synoptic maps and three-dimensional spatial atmospheric analyses. The first meteorological satellite was launched in 1960. Weather radar, airplane observation and wind and air temperature profilers take place since then. A description of these developments in Europe are the main subject of this study. Criteria for vertical profile observation, data processing and analysis have  been continuously done by the World Meteorological Organization and their development by states and European Union research projects including COST actions. Details are also represented.

KEY WORDS: vertical profiling of atmosphere, Europe, COST actions

How to cite: Pandzic, K. and Likso, T.: Profiling the Atmospheric Boundary Layer at European Scale - COST Action, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20728, https://doi.org/10.5194/egusphere-egu2020-20728, 2020.

EGU2020-11216 | Displays | GI1.2

X-MINE project (H2020): testing the capabilities of X-ray techniques in drill core scanning and ore sorting

Marian Munteanu, Stefan Sädbom, Janne Paaso, Mikael Bergqvist, Nikolaos Arvanitidis, Ronald Arvidsson, Jacek Kolacz, Evangelos Bakalis, Desislav Ivanov, Kleio Grammi, Juha Kalliopuska, Stepan Polansky, Michael Gielda, Jan-Erik Björklund, Lotta Sartz, Karin Högdahl, Paul Attiwell, Edward Lynch, Stefan Luth, and Edine Bakker

The X-MINE project (Real-Time Mineral X-Ray Analysis for Efficient and Sustainable Mining), under the Horizon 2020 program (grant agreement no. 730270), combines high-energy XRF sensors, multi-energy XRT sensors and optical sensors to be able to support both drill core analysis and mineral sorting applications, including high speed processing of low-grade ores.

The aims of the project are: (1) smart exploration, (2) selective (more efficient) drilling and (3) optimal extraction in existing mine operations. The expected effects of project outputs include: reduced quantity of mining waste by a better selection of the ore; reduced consumption of energy, explosives and other chemicals thus less CO2 and NO2 emissions; further critical raw materials acquisition for the EU; better planning of mining operations; increased resource efficiency.

On the purpose of smart exploration, multi-parameter 3D near-mine ore deposit models were built, under SGU coordination, for 4 mining areas: Lovisagruvan(Sweden), Assarel(Bulgaria), Skouriotissa-Apliki(Cyprus) and Mavres Petres-Piavitsa(Greece).

The project improves and combines various online sensing technologies, integrates the multi-sensor solution in an online analysis platform and demonstrates the solution in real mining operations. Two prototypes are being developed and demonstrated in the X-MINE project.

(1) A sensitive transportable X-ray Analyser based on undertaken drill core scanning (GeoCore X10, delivered by Orexplore and further developed within X-Mine project). This performs penetrative combined and integrated XRF-XRT scanning, providing assaying of exploration drill cores and 3D tomographic imaging, that also allows linear and structural annotations and measures bulk density.

(2) A complex analyser, developed by X-Mine consortium, integrated in a sorting line by Comex. The multisensory analyser unit uses XRT-XRF based scanners and 3D cameras, platforms, algorithms and software developed by Orexplore, VTT, Advacam, and Antmicro.

The X-Mine project has reached the phase of pilot demonstration. The prototypes are being tested on various types of mineralisations and rocks from the four operating mines mentioned above. The tests done so far showed that the drill core scanner allows the tomographic observation and structural study of the cores, which could be ore-genetically evaluated and interpreted. Elemental composition is analysed and bulk density is measured for 1 m of core and calculated for segments as short as 8 mm based on estimated mineralogy. The scanning can be done at a speed of 3-4 meters of NQ-size drill core per hour with results available immediately and therefore useful while the drill rig is still on site.

The development of the new X-MINE sorting application started with laboratory and full-scale tests, and base line studies of previously available dual-energy X-ray technology. A first full-scale initial test at Lovisagruvan indicated that 75% of available size fractions are amenable for sorting, although alternative crushing/size screening may increase sortable fractions. Laboratory and base line studies performed so far, at a speed of 17-20 tons / hour, indicate that waste rock may be reduced by as much as 22 % for some materials.

The testing of the prototypes continues, with special focus on the calibration for different matrix/grade combinations and optimization of hardware, software, algorithms and productivity.

How to cite: Munteanu, M., Sädbom, S., Paaso, J., Bergqvist, M., Arvanitidis, N., Arvidsson, R., Kolacz, J., Bakalis, E., Ivanov, D., Grammi, K., Kalliopuska, J., Polansky, S., Gielda, M., Björklund, J.-E., Sartz, L., Högdahl, K., Attiwell, P., Lynch, E., Luth, S., and Bakker, E.: X-MINE project (H2020): testing the capabilities of X-ray techniques in drill core scanning and ore sorting, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11216, https://doi.org/10.5194/egusphere-egu2020-11216, 2020.

EGU2020-11212 | Displays | GI1.2

BSUIN – Baltic Sea Underground Innovation Network

Jari Joutsenvaara and the BSUIN collaboration

The Baltic Sea region hosts numerous underground facilities or underground laboratories (Uls). The Baltic Sea Underground Innovation Network (BSUIN) there are six such facilities, all unique in their characteristics and operational settings, e.g. located in existing or historical mines, research tunnel networks or as a dedicated underground laboratory for a specific purpose. BSUIN project concentrates on the making the Uls more accessible for current and new users,  helping the Uls to understand their infrastructural challenges and possibilities, and through joint marketing to attract a broader spectrum of users into their facilities.

The underground laboratories participating in BSUIN are Callio Lab (Pyhäjärvi Finland), ÄSPÖ Hard Rock Laboratory (Oskarshamn, Sweden), Ruskela Mining Park (Ruskeala, Russia), Educational and research mine Reiche Zeche (Freiberg, Germany), Underground Low Background Laboratory of the Khlopin Radium Institute (St.Petersburg, Russia) and the Conceptual Lab development co-ordinated by KGHM Cuprum R&D centre (Poland).

We will present the overview of the project, key outcomes, findings and recommendations for underground laboratories in general. The key outcomes of the project for the individual underground laboratories consist of characterisation of the structural, geological and operational environments together with information on the governing legislation and authorities for the underground sites. Underground risks and challenges in the underground working environment have been documented to help the further development of the individual underground laboratories. Service designs were developed together with the ULs to enhance user support and to attract a broader spectrum of users.  To help users with innovation and innovation management the variety of the innovation services was documented to be used as bases for the future operational development of the ULs. To support the marketing, coordinate activities and develop the cooperation an umbrella organisation European Underground Laboratories association (EUL) will be established to carry on the work started in BSUIN.

The Baltic Sea Underground Innovation Network, BSUIN, is funded by the Interreg Baltic Sea Region Programme. 

How to cite: Joutsenvaara, J. and the BSUIN collaboration: BSUIN – Baltic Sea Underground Innovation Network , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11212, https://doi.org/10.5194/egusphere-egu2020-11212, 2020.

EGU2020-19835 | Displays | GI1.2

TU1208 GPR Association: Why? How? What?

Lara Pajewski

TU1208 GPR Association (www.gpradar.eu/tu1208/) is a follow-up initiative of COST Action TU1208 “Civil engineering applications of ground penetrating radar” (www.gpradar.eu), which ended in October 2017. The association inherited the same primary objective of the Action, namely, to exchange and increase scientific-technical knowledge and experience of ground penetrating radar (GPR) technique, whilst promoting a wider and more effective use of this safe and non-destructive inspection method. Currently (2019) the association involves 41 Members from 30 Institutes in 14 Countries; participating institutions include universities, research centers, public agencies, GPR manufacturers and end-users. The association is open to experts from all over the world and not 'only' to Members of COST Action TU1208. The research activities supported by the association cover all areas of GPR technology, methodology, and applications.

Why? 

The motivations to maintain, expand and leverage our COST network after the end of the Action could be summarized by saying that during the Action’s lifetime we acquired awareness that “we are stronger together.” There can be different ways to keep a COST network alive after the Action’s end, the most common being continuation through funding of another Action or EU/international collaborative research projects. We realized that establishing an association would offer a great added value. An association is actually a platform to coordinate, complement, and support any new initiatives undertaken by its members; it helps to avoid fragmentation of research, achieve better harmonization of activities and approaches, and constantly attain involvement of new actors. In perspective, an association can potentiate the contact of a community of innovators with policy makers. Moreover, an association gives identity to the group and encourages the discussion of general principles alongside more strictly scientific topics.

How?

TU1208 GPR association was founded in September 2017, before the Action’s Final Conference. The financial model is a non-profit scientific association with statutes, registered with the Italian Revenue Agency. Administrative and operative offices are in Rome. The simplest financial structure was chosen for the association, which has a fiscal code but does not have a VAT number; thus, the association can receive social quotas, donations, and occasionally other types of incomes. This model is the easiest to run and can be upgraded in the future, if useful.

What?

We believe that the key principles and values that we experienced together in COST Action TU1208 continue to matter notwithstanding the Action ended, so we aim to apply them and spread them out.

The association publishes books, proceedings, and educational material. We have founded the first peer-reviewed scientific journal dedicated to GPR, “Ground Penetrating Radar” (www.gpradar.eu/journal/): this is the most challenging and ambitious initiative that the association has initiated and carried out so far. Our publications are distributed in true open access, free to both Authors and Readers.

We organize networking and educational events, such as workshops, training schools, roundtables and scientific sessions in international conferences (including the EGU session «COST Actions in Geosciences», wherein this abstract is presented, and the EGU session «Ground Penetrating Radar: Technology, Methodology, Applications, and Case Studies»). The association has also funded/co-funded a few scientific missions.

How to cite: Pajewski, L.: TU1208 GPR Association: Why? How? What?, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19835, https://doi.org/10.5194/egusphere-egu2020-19835, 2020.

Scientists and experts participating in COST Actions can benefit from a wide range of COST networking tools. Meetings, workshops, conferences and training schools can be organized. Short-term scientific missions (STSM) can be funded: these are exchange visits where an Action Member spends five days up to six months abroad, in a host institution; the aim of STSMs is to foster collaboration between institutions and sharing of new techniques that may not be available in a participant’s home institution. COST also funds dissemination and communication of Action’s outcomes within research communities and beyond. Finally, conference grants for early-career researchers from Inclusiveness Target Countries (ITC) aim at helping participants from ITC to attend international science and technology related conferences that are not organised by COST Actions.

In this presentation, we discuss the challenges and lessons learnt in COST Action TU1208 “Civil engineering applications of ground penetrating radar” [1] while using COST networking tools to fulfill the objectives of the Action, enhance its impact, and maximize the benefits of its Members. We consider one tool at a time focusing on the obstacles that we encountered and how we overcame them, as well as giving hints on how the Action and its Members made the most from the use of the tool. We describe how the use of the tools changed during the Action’s lifetime. 

COST networking tools can of course be used in a customary way and they are all extremely frutiful. More creative solutions can be implemented too, to keep Members engaged or achieve particular goals. Therefore, this presentation continues with examples of less-common exploitations of the tools in TU1208. For instance, we used the “Meeting” tool for the organization of a series of science communication initiatives aimed at increasing public awareness about ground penetrating radar capabilities and applications and at establishing a dialogue with policymakers, stakeholders and end-users of our research (TU1208 GPR RoadShow [2]); the Roadshow included non-scientific workshops, practical demonstrations, and a series of educational activities with children and citizens. We repeatedly exploited the “Meeting” tool also for one week gatherings with a small number of Members, where we worked full-time together at bringing forward specific Action’s activities, one of the challenges of COST Actions being the lack of funds to finance research and the difficulty to “make Members work” for the Action when they are at their home institutions.

We hope that recently started Actions can build upon our experience.

 

[1] L. Pajewski, A. Benedetto, X. Dérobert, A. Giannopoulos, A. Loizos, G. Manacorda, M. Marciniak, C. Plati, G. Schettini, I. Trinks, "Applications of Ground Penetrating Radar in Civil Engineering – COST Action TU1208," Proc. 7th IWAGPR, 2013, Nantes, France, pp. 1-6, doi.org/10.1109/IWAGPR.2013.6601528

[2] L. Pajewski, H. Tõnisson, K. Orviku, M. Govedarica, A. Ristić, V. Borecky, S. S. Artagan, S. Fontul, and K. Dimitriadis, “TU1208 GPR Roadshow: Educational and promotional activities carried out by Members of COST Action TU1208 to increase public awareness on the potential and capabilities of the GPR technique,” Ground Penetrating Radar, Volume 2(1), March 2019, pp. 67-109, doi.org/10.26376/GPR2019004

How to cite: Ristic, A., Pajewski, L., Govedarica, M., and Vrtunski, M.: Use of COST networking tools to achieve the objectives of a COST Action, enhance its impact, and maximize the benefits of its Members – challenges and lessons learnt in COST Action TU1208, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19699, https://doi.org/10.5194/egusphere-egu2020-19699, 2020.

EGU2020-20324 | Displays | GI1.2

The European Astrobiology Institute – a sustainable structure launched by a COST Action and other European initiatives

Wolf Geppert

EGU2020-13066 * | Displays | GI1.2 | Highlight

BioLink: Linking belowground biodiversity and ecosystem function in European forests

Douglas Godbold, Mark Bakker, Ivanno Brunner, and Martin Lukac

Biodiversity of ecosystems is an important driver for the supply of ecosystem services to people. Soils often have a larger biodiversity per unit surface area than what can be observed aboveground. Here, we present what is to our knowledge, the most extensive literature-based key-word assessment of the existing information about the relationships between belowground biodiversity and ecosystem services in European forests. The belowground diversity of plant roots, fungi, prokaryota, soil fauna, and protists was evaluated in relation to the supply of Provisioning, Regulating, Cultural, and Supporting Services. The soil biota were divided into 14 subgroups and the ecosystem services into 37 separate services. Out of the 518 possible combinations of biotic groups and ecosystem services, no published study was found for 374 combinations (72%). Of the remaining 144 combinations (28%) where relationships were found, the large majority (87%) showed a positive relationship between biodiversity of a belowground biotic group and an associated ecosystem service. We concluded that (1) soil biodiversity is generally positively related to ecosystem services in European forests; (2) the links between soil biodiversity and Cultural or Supporting services are better documented than those relating to Provisioning and Regulating services; (3) there is a huge knowledge gap for most possible combinations of soil biota and ecosystem services regarding how a more biodiverse soil biota is associated with a given ecosystem service. Given the drastically increasing societal demand for knowledge of the role of biodiversity in the functioning of ecosystems and the supply of ecosystem services, we strongly encourage the scientific community to conduct well-designed studies incorporating the belowground diversity and the functions and services associated with this diversity.

How to cite: Godbold, D., Bakker, M., Brunner, I., and Lukac, M.: BioLink: Linking belowground biodiversity and ecosystem function in European forests, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13066, https://doi.org/10.5194/egusphere-egu2020-13066, 2020.

EGU2020-11057 | Displays | GI1.2

Growing the Urban Forest. From our Practitioners’ perspective to Field Initiatives

Maria Beatrice Andreucci and Naomi Zürcher

EGU2020-10977 | Displays | GI1.2

Carbonate System and Acidification of the Adriatic Sea

Valentina Turk, Nina Bednarsek, Jadran Faganeli, Blaženka Gasparovic, Michele Giani, Roberta Guerra, Nives Kovac, Alenka Malej, Bor Krajnc, Donata Melaku Canu, and Nives Ogrinc

Although the marginal seas represent only 7% of the total ocean area, the CO2 fluxes are intensive and important for the carbon budget, exposing to an intense process of anthropogenic ocean acidification (OA). A decline in pH, especially in the estuarine waters, results also from the eutrophication-induced acidification. The Adriatic Sea is currently a CO2 sink with an annual flux of approximately -1.2 to -3 mol C m-2 yr-1 which is twice as low compared to the net sink rates in the NW Mediterranean (-4 to -5 mol C m-2 yr-1). Based on the comparison of two winter cruises carried out in in the 25-year interval between 1983 and 2008, acidification rate of 0.003 pHT units yr−1 was estimated in the northern Adriatic which is similar to the Mediterranean open waters (with recent estimations of −0.0028 ± 0.0003 units pHT yr−1) and the surface coastal waters (-0.003 ± 0.001 and -0.0044 ± 0.00006 pHT units yr−1). The computed Revelle factor for the Adriatic Sea, with the value of about 10, indicates that the buffer capacity is rather high and that the waters should not be particularly exposed to acidification. Total alkalinity (TA) in the Adriatic (2.6-2.7 mM) is in the upper range of TA measured in the Mediterranean Sea because riverine inputs transport carbonates dissolved from the Alpine dolomites and karstic watersheds. The Adriatic Sea is the second sub-basin (319 Gmol yr-1), following the Aegean Sea (which receives the TA contribution from the Black Sea), that contribute to the riverine TA discharges into the Mediterranean Sea. About 60% of the TA inflow into the Adriatic Sea is attributed to the Po river discharge with TA of ~3 mM and TA decreases with increasing salinity. Saturation state indicates that the waters of the Adriatic are supersaturated with respect to calcite (ΩCa) and aragonite (ΩAr) throughout the year. However, saturation states are considerably lower in the bottom water layers, due to the prevalence of benthic remineralization processes in the stratification period. The seasonal changes of the chemical and environmental conditions and relatively small size of the Adriatic Sea area the microbial community composition, function (growth, enzymatic activity) and carbon and nitrogen biogeochemical cycles. Significant effects on calcifying organisms and phytoplankton are expected while the effects of possible OA on microbially-driven processes are not known yet.

How to cite: Turk, V., Bednarsek, N., Faganeli, J., Gasparovic, B., Giani, M., Guerra, R., Kovac, N., Malej, A., Krajnc, B., Melaku Canu, D., and Ogrinc, N.: Carbonate System and Acidification of the Adriatic Sea, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10977, https://doi.org/10.5194/egusphere-egu2020-10977, 2020.

EGU2020-1282 * | Displays | GI1.2 | Highlight

COST Action LAND4FLOOD - Natural Flood Retention on Private Land: Overview of recent activities and future plans

Nejc Bezak, Lenka Slavíková, and Thomas Hartmann

Every devastating large flood usually leads to initiation of different flood risk reduction activities. There are numerous options available how to approach flood risk management. Only limited part of approaches considered land management as significant topic in the flood risk management. Therefore, efficient and effective land management for flood retention and resilience is needed. COST action LAND4FLOOD (CA 16209) deals with natural flood retention on private land. More information about the specific cost action can be found on the web-page http://www.land4flood.eu/ and LAND4FLOOD twitter account @Land4Flood.

Some of the recent activates of the COST action include:

-Organization of series of workshops on different topics such as “Strategies for achieving flood resilience”, “Delivering Nature-Based Solutions (NBS)”, “NBS for flood retention in Southern Europe”, “Compensation Mechanism for Flood Storage”, “Innovative and successfully implemented strategies for achieving resilience in Flood Risk Management with a special focus on private and public property flood resilience” and organization of stakeholders meetings.

-Publication of policy briefs entitled “How Private Land Matters in Flood Risk Management?” that is also translated in French and Spanish and “Compensation for Flood Storage” that is available in Portuguese, Spanish, Czech and French versions.

-Support of multiple Short Term Scientific Missions (STSM) and ITC and conference grants.

-Publication of book about “Nature-based Flood Risk Management on Private Land” and multiple scientific papers.

-Preparation of the LAND4FLOOD leaflet (i.e. http://www.land4flood.eu/wp-content/uploads/2019/10/Leaflet-LAND4FLOOD-final.pdf) that is translated into Albanian, Bulgarian, Slovakian and Slovenian languages.

Moreover, the COST action will finish in September 2021, thus there are still several ongoing projects such as open STSM calls, workshop initiations, research project application and book proposals. For example, a recent book proposal that has just been launched will review what we know about flooding land and how to implement spatial flood risk management and resilience. More specifically, as pointed out land is needed for flood risk management. Thus, to store excess water and retain it without major damage. However, this land is often in private ownership. This book proposal will explore different options regarding storage of water in the catchment during flood events: in the hinterland with decentral measures, along the rivers in polders, washlands and in resilient cities. The book will put the focus on land as a biophysical system (including hydrological aspects), as a socio-economic resource, and as a possible solution for flood risk reduction (i.e. asking for policy interventions to activate the land for flood protection measures). These three areas (i.e. hinterland, along the streams, in resilient cities) and the three analytical lenses (i.e. processes to influence stakeholders and interests in land, socio-economic context of land and environmental conditions of land for retention) will indicate how to use land to reduce the impact of flooding.

How to cite: Bezak, N., Slavíková, L., and Hartmann, T.: COST Action LAND4FLOOD - Natural Flood Retention on Private Land: Overview of recent activities and future plans, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1282, https://doi.org/10.5194/egusphere-egu2020-1282, 2020.

EGU2020-22143 | Displays | GI1.2

Perspectives for Planning Approaches in Promoting Underground Built Heritage - COST Action Underground4value

Carlos Smaniotto Costa, Tatiana Ruchinskaya, and Konstantinos Lalenis

The COST Action 18110 Underground4value (http://underground4value.eu) aims to advance knowledge on how to guarantee continuity of use and significance of underground historic fabric. It is collecting information, experiences and knowhow to base the development of research and training. The Action focusses on underground regeneration, revitalisation of the public realm and skills development for people concerned with underground heritage.

This contribution centres the attention of the Working Group on Planning Approaches. It also looks at the role of local authorities, as enablers and facilitators, in coordination, use  and management of underground built heritage. In this framework underground built heritage is considered as a social resource with integrated programmes of physical, economic and social measures, backed by strategic stakeholder dialogue.

On the one hand, this contribution discusses the structure and goals of the WG, as it pays attention to the necessary complementarities between functional approaches – at the level of regions and city – and social and cultural approaches involving citizens’ engagement and empowerment – at the local level. This WG aims to provide a reflection on sustainable approaches to preserve the underground built heritage and, at the same time, to unfold the case by case approach for potential use of underground space. On the other hand, to achieve its objectives the WG on Planning Approaches is setting together potentials and constraints in the efforts to make better use of underground heritage. This contribution, therefore, sheds lights on the preliminary results of the WG. It is centred on the learned lessons, challenges and barriers - from a planning science perspective - that experts met in their efforts to tackle Underground Built Heritage. Achieving this goal makes the call for an educational paradigm shift - as the Action is not only interested in compiling the results, rather on experiences that can be analysed and learned. This requires a dynamic understanding of knowledge, abilities and skills, towards creating more effective coalitions of ‘actors’ within localities, by developing structures, which encourage long term collaborative relationships. Enabled by the gained knowledge, the WG will define the best tailored ways to forward this knowledge for planners and decision-makers.

How to cite: Smaniotto Costa, C., Ruchinskaya, T., and Lalenis, K.: Perspectives for Planning Approaches in Promoting Underground Built Heritage - COST Action Underground4value, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22143, https://doi.org/10.5194/egusphere-egu2020-22143, 2020.

EGU2020-20601 | Displays | GI1.2

A European Network for Extreme Atmospheric Events Detection and Monitoring

Riccardo Biondi and Stefano Corradini

Deep convective systems and explosive volcanic eruptions are destructive events causing deaths, injuries, damage to infrastructure. They account for the major economic damages in several countries, present several serious hazards to society, including impact to aviation safety and potential longer-term deleterious effects on weather and climate. The number and the intensity of severe convective events have increased in the last decades in some areas of the globe including Europe and it is going to further increase in a climate change environment. Relatively small eruptions could affect the economy of an entire continent as demonstrated in 2010 by the Eyjafjallajokull eruption. Due to the multi- and trans-disciplinary effects at local, regional and global scales, convective and volcanic clouds include impacts to several economic sectors such as telecommunications, transportation, health, insurances, agriculture, solar energy etc., raising the interest of diverse stakeholders and policymakers. However, the coordination between the different communities is still very difficult. On the one hand, measurement products lack harmonised quality indicators, data formats and measurement schedules. On the contrary, current attempts to transfer tailored products to end-users are not coordinated, and the same technological and social obstacles are tackled individually by different groups, a process that makes the use of data slow and expensive. The flow of information and knowledge between measurement, models, and society requires translation across disciplinary and cultural boundaries. The result is that current data-model-user cooperation becomes increasingly fractured and a potentially immense benefit for Europe’s end users remains unexplored. 

The overall objective of this action is to establish a network involving different communities interested on extreme atmospheric events, such as pilots, aircraft engines manufacturers, air traffic managers, modellers, aircraft companies, atmospheric physicists, meteorologists, policymakers and stakeholders. The network should coordinate the research activity for creating user-oriented operational and tailored products, understanding the needs of final users, to define a standard product format easily understandable by all the players, better coordinate the early warning activities, and establishing a new fast and efficient information transfer process within all the parties at international level. From scientific point of view, there is an urgent need to share ideas among scientists in nearby fields, to educate and train future researchers in the techniques and instruments for monitoring, detecting and modeling “extreme clouds”, to develop new techniques and to integrate data coming from different systems. Extreme atmospheric events do not have any border, thus the involvement of as many countries as possible would be beneficial for the action. The monitoring network of such kind of phenomena is not adequate in several countries due to different reasons such as unpopulated areas, political instability, and poverty. Conversely, availability of observational data from source regions is fundamental for monitoring and forecasting. Thus, the involvement and collaboration with near neighbour countries is very important. We have already established a good network with the aim of creating a future COST Action on this topic, with 23 countries and 35 different institutes involved but we are still missing collaborations from several eastern and southern European countries.

How to cite: Biondi, R. and Corradini, S.: A European Network for Extreme Atmospheric Events Detection and Monitoring, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20601, https://doi.org/10.5194/egusphere-egu2020-20601, 2020.

EGU2020-13645 | Displays | GI1.2

Ground penetrating radar investigations in Quebrada Montes, Lobitos, Peru

Lai Bun Lok, Diego Almendrades, Michael Alderson, Alejandro Pizarro, Andres Bustamante, and John Shi

The dry equatorial forests in the north-western coast of Peru suffer from acute water stress and man-driven deforestation. Recent estimates indicate that the forests have reduced to approximately 10% of their original size. There are local reforestation efforts currently underway, for example to prevent the extinction of native species such as the Peruvian Plantcutter songbird (Phytotoma raimondii). However, irrigation needed to support such efforts is severely challenged by the issues of water scarcity in the region. These adverse effects are also being experienced at a local level by the nearby rural community in Lobitos.

The groundwater resources in Lobitos could potentially offer a solution to the above issues for the local community. However, a scientifically informed and sustainable method of mapping and utilising this resource is needed. To provide supporting evidence in this effort, an extensive ground penetrating radar survey was conducted using a commercial 80 MHz impulse radar to characterise the near subsurface within a 90 hectare plot called Ecológica Tallán, which is part of a natural dry water channel in Quebrada Montes and declared as an important conservation area for the district.

Through a pilot study between Lancaster University, EcoSwell Peru and University of Glasgow, we report on initial results from our ground penetrating radar survey to provide a better understanding of the subsurface characteristics in Quebrada Montes, Lobitos.

 

How to cite: Lok, L. B., Almendrades, D., Alderson, M., Pizarro, A., Bustamante, A., and Shi, J.: Ground penetrating radar investigations in Quebrada Montes, Lobitos, Peru, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13645, https://doi.org/10.5194/egusphere-egu2020-13645, 2020.

EGU2020-7248 | Displays | GI1.2

The Norwegian node for the European Multidisciplinary Seafloor and water column Observatory

Thibaut Barreyre, Ilker Fer, and Bénédicte Ferré

NorEMSO is a coordinated, large-scale deep-ocean observation facility to establish the Norwegian node for the European Multidisciplinary Seafloor and water column Observatory (EMSO). The project aims to explore the under-sampled Nordic Seas to gain a better understanding of the critical role that they play in our climate system and global ocean circulation. An overarching scientific objective is to better understand the drivers for the temporal and spatial changes of water mass transformations, ocean circulation, acidification and thermo-chemical exchanges at the seafloor in the Nordic Seas, and to contribute to improvement of models and forecasting by producing and making available high quality, near real time data. NorEMSO will achieve this by combining expansion of existing and establishment of new observatory network infrastructure, as well as its coordination and integration into EMSO.

NorEMSO comprises of three main components: moored observatories, gliders, and seafloor and water column observatory at the Mohn Ridge (EMSO-Mohn).

Moored observation systems include an array of four moored observatories located at key positions in the Nordic Seas (Svinøy, Station M, South Cape, and central Fram Strait).

Gliders will be operated along five transects across both the Norwegian and the Greenland Seas to monitor circulation and water mass properties at those key locations. Transects in the Norwegian and Lofoten basins will focus on monitoring the Norwegian Atlantic Current, and a transect in Fram Strait will monitor properties and variability in the return Atlantic Water along the Polar Front in the northern Nordic Seas. In addition, transects in the Greenland and Iceland Seas will address the water mass transformation processes through wintertime open ocean convection, and the southbound transport of surface water from the Arctic Ocean and dense water that feeds the lower limb of the Atlantic Meridional Overturning Circulation in the East Greenland Current.

EMSO-Mohn will establish, at the newly discovered hydrothermal site on the Mohn Ridge, a fixed-point seabed-water-column-coupled and wireless observatory with a multidisciplinary approach – from geophysics and physical oceanography to ecology and microbiology. It is primarily directed at understanding hydrothermal fluxes and associated hydrothermal plume dynamics in the water column and how it disperses in an oceanographic front over the Mohn Ridge.

Following EMSO philosophy, NorEMSO will provide data and platforms to a large and diverse group of users, from scientists and industries to institutions and policy makers. The observations will serve climate research, ocean circulation understanding, numerical operational models, design of environmental policies, and education.

How to cite: Barreyre, T., Fer, I., and Ferré, B.: The Norwegian node for the European Multidisciplinary Seafloor and water column Observatory, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7248, https://doi.org/10.5194/egusphere-egu2020-7248, 2020.

EGU2020-3052 | Displays | GI1.2

LIDI 2 – New Evaluation Strategy for Accurate and Precise Clumped Isotope CO2 Analysis on Carbonate Samples

Magda Mandic, Mario Tuthorn, Nils Stoebener, Jens Radke, and Johannes Schwieters

Long Integration Dual Inlet (LIDI) is an established technology which enabled improved accuracy and precision of Δ47 analysis from carbonate samples by utilizing sequential measurement of the full sample and reference, rather than alternating between sample and reference on shorter time periods, as it is done in the classical Dual Inlet method. As of today, there are two key challenges that were limiting further improvements to Δ47 determination: the IRMS must be in a stable temperature environment during long measurement of sample and reference gas, and the crimping of the sample and reference capillaries must be precisely matched, otherwise the produced data will be inaccurate and have reduced precision.

Here we present the improvements made on the sample gas measurement and data evaluation, which we define as LIDI 2.

By applying the LIDI 2 method, sample bracketing is possible following a four-step approach, resulting in fully corrected temperature drift (i.e. eliminated from the data), decreasing the standard deviation by factor of 2. This is a substantial improvement for acquiring clumped isotope data as reaching a very stable temperature of ±0.1°C/h is a challenge for most laboratories.

Alongside eliminating variation in the Δ47 data caused by unstable laboratory air temperature, LIDI 2 also improves the overlap of sample and reference gas signals due to non-perfect crimping of the capillaries. The crimping procedure is laborious and rarely delivers perfect results. Additionally, the pressure adjustment before reference measurement must ensure there is no significant offset between sample and reference intensities. LIDI 2 delivers perfect sample versus reference intensity matching, which results in significantly higher precision on each sample gas analyzed. Standard error of a single sample measurement is improved by up to factor of 2.

The LIDI 2 method delivers improved accuracy and precision on Δ47 measurement from small Carbonate samples, which in combination with the latest advancements in inert capillaries coating and automated contaminant trapping contributes to enhanced clumped isotopes data quality.

 

How to cite: Mandic, M., Tuthorn, M., Stoebener, N., Radke, J., and Schwieters, J.: LIDI 2 – New Evaluation Strategy for Accurate and Precise Clumped Isotope CO2 Analysis on Carbonate Samples, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3052, https://doi.org/10.5194/egusphere-egu2020-3052, 2020.

Geodesists have a different mindset; major or minor involvement in mapping, navigation, positioning, surveying, gravity, coordinate frames and systems, geographical information systems, photogrammetry, 3D laser scanning, satellite orbit determination, orbital mechanics, interferometry and many other fields all help in the grand builtup of a resilient scientist who can emerge with an explorer attitude towards various facets of life; archaeology being one of them, needless to say. If this hybrid composite of mindset and attitude is combined with disciplined and smart usage of geophysical 3D imaging instrumentations deployed frequently by treasure hunters, geodesists might be in a very unique position to make a big bang in the world; finding archaeological Black Swans that might serve to rewrite certain narratives of ancient history is something geodesists must consider deeply. In this presentation, an approach and a discovery will be presented.

How to cite: Hawarey, M.: A Geodesist's Involvement Into Archaeology; A Beginning of Huge Discoveries, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17, https://doi.org/10.5194/egusphere-egu2020-17, 2020.

GI1.3 – The use of historical images and high resolution topography in geosciences

Today, photos play an important role in geoscience and public discussion. When photographical techniques developed during the second half of the 19th century, it took several decades uuntil high mountain areas and specific features could be captured with this technique, as a follow upt o traditional paintings and drawings. In European geography, Friedrich Simony developed the idea of tackling geomorphological processes by time lapse photography. Contemporary literature shows that his technique of combining photography with empirical data and theories was convincing, and that he established a new style of scientific discussion. Still, the comparison of historical with contemporary photography offers scientific insights and information which is not covered by any other type of empirical evidence as measurements, maps or descriptions. For example not only extent, but also firn and debris cover of glaciers, information on type and extent of vegetation,  the width and style of roads, details of infrastructure and cultural practices can be tackled from early photographs.  Several archives do allow not only acess to photographic documents, but also to metadata. Interdisciplinary effort has to be taken to further analyse this wealth of information.

How to cite: Fischer, A.: The role of repeat photography in establishing theories of transition in high mountain environments, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7070, https://doi.org/10.5194/egusphere-egu2020-7070, 2020.

EGU2020-19910 | Displays | GI1.3

Unearthing the forgotten record of glacier change in southeast Greenland

Michael Cooper, Paulina Lewinska, Julian Dowdeswell, Edwin Hancock, William Smith, and David Rippin

Prior to the satellite era (pre-1970s) knowledge of long-term glacier change is sparse. Although some glacier-wide mass balance datasets are available, few records extend beyond twenty years in length, or indeed, start prior to the 1980s; as such, identifying long-term trends between glacier change and global temperatures is difficult. As a result, extending the record of glacier change will not only help to identify such trends, but may also facilitate more robust understanding of future glacier response under a perturbed and varying climate.

Since the ‘heroic age of Arctic (and Antarctic) exploration’, many photographs of polar environments have been captured and stored for historic interest. These photographs, depicting images of past glaciers and ice sheet margins, have, as of yet, untapped potential to provide important insights into past glacier extent, and long-term behaviour.

Using computer-vision methodologies, we present a unique record of georeferenced 3-D elevation models using declassified aerial imagery dating from the 1930s—1980s at quasi-regular time steps. This study focusses upon two sections (ca. 190 km total length) of the southeast margin of the Greenland Ice Sheet (in the vicinity of Kangerlussuaq Glacier), capturing the history of both land- and marine-terminating outlet glaciers, and local glaciers. We examine quantitative information extracted from these reconstructions, allowing us to ‘back extend’ the record of glacial change in this region, by measuring changes in glacial extent, surface profiles and height (elevation), and calculating volume estimates.

How to cite: Cooper, M., Lewinska, P., Dowdeswell, J., Hancock, E., Smith, W., and Rippin, D.: Unearthing the forgotten record of glacier change in southeast Greenland, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19910, https://doi.org/10.5194/egusphere-egu2020-19910, 2020.

EGU2020-9153 * | Displays | GI1.3 | Highlight

Multidecadal elevation changes from spy satellite images: application to glaciers and landslides

Amaury Dehecq, Alex Gardner, Oleg Alexandrov, David Shean, and Pascal Lacroix

Earth’s surface has evolved dramatically over the last 50 years as a consequence of anthropogenic activities and climate change. The observation of such changes at decadal scales is often limited to sparse in-situ observations. The growth of satellite remote-sensing has enabled such monitoring at regional/global scales but generally over less than two decades.

More than 2 million images have been acquired by American reconnaissance (“spy”) satellites on photographic film from the 1960s to the 1980s, and progressively declassified. With near-global coverage and meter to sub-meter resolution, these images have a large potential for many geoscience applications. However the photographic archive represents a unique set of challenges: pre-processing of the scans, correction of the image distortion caused during storing and scanning, poorly known camera positions and parameters. The vast majority of studies using these data rely on tedious manual processing of the data, hindering regional scale applications.

Here, we present the existing datasets and the development of an automated processing pipeline. We will focus in particular on images acquired by the Hexagon mapping camera (1973-1980, 12 missions) at 6-9 m ground resolution. A fully automated workflow has been developed to detect the 1081 fiducial markers present on the image, correct for distortion and stitch the different parts of the image, scanned in multiple sections. The pre-processed images are then used to generate Digital Elevation Models (DEMs) at 24 m resolution with the open-source NASA Ames Stereo Pipeline. The developed workflow is able to automatically solve for the unknown camera positions/orientations and optimally aligns the DEMs to an ancillary DEM for the determination of elevation changes. The application to ~600 images has revealed systematic biases in the retrieved elevation, up to 30 m error, linked to uncertainties in the camera parameters (focal length, lens distortion). We present a methodology to refine these parameters using an ancillary DEM only, without use of manual Ground Control Points. The KH-9 elevation is then validated against existing maps in Europe and Alaska and shows a vertical accuracy of ~5 m (68% interval) to 10-15 m (95% interval), sufficient for the study of large surface deformation (glaciers, landslides).

Finally, we conclude with several use of these data for the estimation of 40 years geodetic glacier mass balance in Europe and Alaska, and irrigation-triggered landslides in South Peru.

How to cite: Dehecq, A., Gardner, A., Alexandrov, O., Shean, D., and Lacroix, P.: Multidecadal elevation changes from spy satellite images: application to glaciers and landslides, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9153, https://doi.org/10.5194/egusphere-egu2020-9153, 2020.

Most large-format analogue aerial photography, especially in the form of roll negatives, is now held in centralised archives, but much still exists elsewhere, notably in the form of positive prints. Whilst many large archiving bodies have been and continue to digitise their holdings of such aerial photography using professional photogrammetric scanners, they are often prohibitive (on the grounds of cost and/or logistics) for use with low-volume, dispersed collections. Therefore, alternative methods are sought, which are presented here. Such alternatives can be subject to relatively poor geometric accuracy, making photogrammetric processing problematic. Here the results of photogrammetric processing with prints digitised using alternative methods are compared and contrasted with digitised roll negatives of the same frames. The quality of resulting elevation data are assessed against reference elevations, using a test site with topography which has remained stable over decades.

How to cite: Ford, A. and Papworth, H.: Digitising archive large-format analogue aerial photography with alternative methods; Implications for photogrammetric processing, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20294, https://doi.org/10.5194/egusphere-egu2020-20294, 2020.

EGU2020-6255 | Displays | GI1.3

Orthomosaics of Historical Aerial Photographs and Horizontal Accuracy Analysis

Ji Won Suh and William Ouimet

Orthomosaics from aerial photographs play a pivotal role in understanding land-use/land cover in broad area and the advent of image processing technology allows us to produce orthoimagery. However, recent advanced technologies are seldom applied to produce historical orthophotos from early or mid 20C old aerial photos in broad extent since they have limited information (e.g. camera position, flying altitude, and yaw) which is critical information for orthomosaics. In this context, this study aims to orthomosaic and georectify historical aerial photographs and validate the horizontal accuracy of orthomosacicked outputs. In order to achieve this, firstly, we collected 117 aerial photographs of 1934 (scale 1:12,000) and 68 of 1951 (scale 1:20,000) from UConn air photo achieve focused on Woodstock town in Connecticut, USA. Secondly, we created GCPs (Ground Control Points) as referenced points where they have not changed over time by overlaying multiple datasets such as LiDAR DEM, hillshade map, recent orthoimagery. Thirdly, we align photos with Control Points (CPs), build a mesh, and build orthomosaics of 1934 and 1951, respectively, using Agisoft Photoscan 1.5. Lastly, calculating RMSE (Root Mean Square Error) and offsets comparing between set of GCPs and CPs from Lidar DEM and set of them digitized from orthomosaics. As a result, RMSE values of GCPs and CPs between 1934 and 1951 mostly show that output of this work is acceptable to use for standard mapping and GIS work or visualization based on ASPRS 1990 horizonal accuracy standard. In addition, we found several factors affect horizontal accuracy of orthomosaics; resolution of aerial photos, spatial distribution of GCPs and CPs, the number of CPs and GCPs, the percentage of lateral overlapping area along flight strips, and margin area. Overall, applying automated orthomosaicking image processing to historical aerial photographs has the potential to represent historical landscape and even detect its change in broad extent.

How to cite: Suh, J. W. and Ouimet, W.: Orthomosaics of Historical Aerial Photographs and Horizontal Accuracy Analysis, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6255, https://doi.org/10.5194/egusphere-egu2020-6255, 2020.

Countrywide surface models from historical panchromatic and true color stereo imagery – a retrospective analysis of forest structures in Switzerland

Mauro Marty1, Lars T. Waser1, Christian Ginzler1

1 Swiss Federal Institute for Forest, Snow and Landscape Research WSL,
Zürcherstrasse 111, CH - 8903 Birmensdorf, Switzerland

Remote sensing methods allow the acquisition of 3D structures of forests over large areas. Active systems, such as Airborne Laser Scanning (ALS) and Synthetic Aperture Radar (SAR) and passive systems, such as multispectral sensors, have been established to acquire 3D and 2.5D data of the earth's surface. Nationwide calculations of surface models with photogrammetric methods from digital stereo aerial images or ALS data are already in operation in some countries (e.g. Switzerland, Austria, some German states).

The availability of historical stereo aerial images allows the calculation of digital surface models from the past using photogrammetric methods. We present a workflow with which we have calculated nationwide surface models for Switzerland for the 1980s, 1990s and 2000s. Current surface models are available from the National Forest Inventory (LFI) Switzerland.

In the context of the Swiss land use and land cover statistics, the Federal Office of Topography (swisstopo) scanned and oriented the analogue black and white stereo aerial photographs with a mean scale of ~1:30'000 of the nationwide flights of 1979 - 84 and1993 - 1997 with 14 µm. The true colour image data from 1998 – 2007 were scanned for the production of the orthoimages swissimage by swisstopo. All these data – the scanned images and the orientation parameters - are also available to the National Forest Inventory (NFI). Within the framework of the NFI, we developed a highly automated workflow to generate digital surface models (DSMs) from many thousands of overlapping frame images covering the whole country. In total, more than 25'000 individual stereo models were processed to nationwide surface models. For their normalization, the digital terrain model of Switzerland 'swissAlti3D' was used. As the image orientation in some areas showed high vertical inaccuracies, corrections had to be made. Data from the Swiss land use and land cover statistics were used for this purpose. At places with constant surface cover since the 1980s (e.g. grassland), correction grids were calculated using the digital terrain model and applied to the surface models.

The results are new data sets on the 2.5D surface of Switzerland from the 1980s, 1990s and 2000s with a high spatial resolution of 1 m. It can be stated that the completeness of the image correlation in forested areas was quite satisfactory. In open areas with agricultural land, however, the matching points were often reduced to the road network, as the meadows and fields in the scanned SW stereo aerial images had very little texture.

This new historical, nationwide data on the horizontal and vertical structure in forests now allows their analysis of changes over the last 40 years.

How to cite: Ginzler, C., Marty, M., and Waser, L. T.: Countrywide surface models from historical panchromatic and true color stereo imagery – a retrospective analysis of forest structures in Switzerland, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12741, https://doi.org/10.5194/egusphere-egu2020-12741, 2020.

EGU2020-22327 | Displays | GI1.3

Development of a 3D Viewer for georeferencing and monoplotting of historical terrestrial images.

Sebastian Flöry, Camillo Ressl, Gerhard Puercher, Norbert Pfeifer, Markus Hollaus, Andreas Bayr, and Wilfried Karel

Mountain regions are disproportionately affected by global warming and changing precipitation conditions. Especially the strong variations within high mountain ranges at the local scale require additional sources in order to quantify changes within this challenging environment. With the emergence of alpine tourism, terrestrial photographs became available by the end of 1800, predating aerial imagery for the selected study areas by 50 years. Due to the earlier availability and oblique acquisition geometry these images are a promising source for quantifying changes within mountainous regions at the local scale. Within the research project SEHAG, methods to process these images and to analyse their potential to quantify and describe environmental changes are developed and applied to study areas in Austria and Italy.

One of the prerequisites for the estimation of changes based on terrestrial imagery is the calculation of the corresponding object point for each pixel in a global coordinate system resulting in a georeferenced orthorectified image. This can be achieved by intersecting the ray defined by the projection center of the camera and each pixel with a digital terrain model, a process known as monoplotting.

So far 1000 terrestrial images with unknown interior and exterior orientation have been collected from various archives for the selected study areas Kaunertal, Horlachtal (both Tyrol, Austria) and Martelltal (South Tyrol, Italy). In order to estimate all camera parameters a 3D viewer for the selection of ground control points has been developed and implemented. The estimation of the exterior and interior orientation is done in OrientAL. 

Preliminary results for selected images show, that especially the developed 3D viewer is an important improvement for the selection of well distributed ground control points and the accurate estimation of the exterior and interior orientation. Monoplotting depends on a digital terrain model, which cannot be computed from the terrestrial images alone due to missing overlap and different acquisitions times. Hence, the combination with historical digital terrain models derived from aerial imagery is necessary to minimize errors introduced due to changes in topography until today. While the large amount of terrestrial images with their oblique acquisition geometries can be exploited to fill occluded areas by combining the results from multiple images, the partly missing or inaccurate temporal information poses another limitation.

With this large image collection, for the first time, we are able to evaluate the use of historical oblique terrestrial photographs for change detection in a systematic manner. This will promote knowledge about challenges, limitations and the achievable accuracy of monoplotting within mountainous regions. The work is part of the SEHAG project (project number I 4062) funded by the Austrian Science Fund (FWF).

How to cite: Flöry, S., Ressl, C., Puercher, G., Pfeifer, N., Hollaus, M., Bayr, A., and Karel, W.: Development of a 3D Viewer for georeferencing and monoplotting of historical terrestrial images. , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22327, https://doi.org/10.5194/egusphere-egu2020-22327, 2020.

EGU2020-595 | Displays | GI1.3

Observing the cryosphere with millimetre wave radar: The case study of Rhône Glacier

William D. Harcourt, David G. Macfarlane, Duncan A. Robertson, Brice Rea, and Matteo Spagnolo

Improving our understanding of the processes governing mass loss from the cryosphere is inhibited by a lack of data at high spatial and temporal resolution. Satellite sensors can provide regional to global scale coverage of glacier processes but fail to resolve processes that occur rapidly, for example glacier calving. To observe these processes, the glaciology community must invest in new techniques that can monitor these processes adequately and fill this major research gap. Here, we will discuss the implementation of an exciting new radar system that is capable of imaging glacial terrain at a high angular resolution and during most weather conditions. The system, named AVTIS2, operates at 94 GHz (~3 mm) and offers a compromise between imaging resolution and penetration through atmospheric obscurants. AVTIS2 scans mechanically across a scene of interest in defined increments of azimuth and elevation angles and generates a 3D data cube of backscattered power. We use a point to maximum power criterion to generate point clouds and construct Digital Elevation Models (DEMs) of the terrain. Because AVTIS2 is a real aperture radar it does not require the phase stability of interferometric radars and can acquire DEMs irrespective of local environmental conditions. In this work, we have used the AVTIS2 radar to map Rhône Glacier in the Swiss Alps, representing the first ever time a millimetre wave radar has been used in this way. To improve our understanding of the performance of AVTIS2 for mapping glaciers, we have characterised the scattering properties of glacial ice at 94 GHz by calculating its Radar Cross Section (RCS). This is key to understanding the performance of AVTIS2 for mapping glaciers. This study represents the first investigation into the reflectivity of ice at millimetre wavelengths and the utility of millimetre wave radar as a surveying tool. We will report on the future application of this instrument in glaciological studies and the unique perspective it can offer.

How to cite: Harcourt, W. D., Macfarlane, D. G., Robertson, D. A., Rea, B., and Spagnolo, M.: Observing the cryosphere with millimetre wave radar: The case study of Rhône Glacier, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-595, https://doi.org/10.5194/egusphere-egu2020-595, 2020.

The geometric characterization of riverbed material is fundamental piece of information for the management of river basins because it allows, for example, the determination of bed-load and hydrodynamics roughness and the study of geo-morphological phenomenona.
However information such the grading curve are not easily achievable by means of traditional field sampling methods, mostly intrusive, and to the hydraulic conditions of rivers that may have high water levels and strong flows.

Multibeam sonars represent an important alternative to traditional survey methods. Nowadays, thanks to advanced scientific knowledge, it is possible to make full use of an equipment increasingly accurate and precise. State of the art solutions have dimensions compact enough to be installed on remotly piloted vehicles and allow to obtained high resolution digital surface models of river beds. The feasibility of having models of such quality and the possibility to conduct surveys more frequently, allowing the monitoring of sedimentation and erosion phenomena as well as the dynamics of the armouring layer, have motivated the development of advanced and innovative technology to analyse these models.

The aim of this work is the development of a workflow that provides an effective method to characterize riverbed material. In order to achieve this target we start from an advanced and original survey technique, that allows to obtain high resolution digital surface models, and use an appropriate post-processing procedure.
We introduce first some results obtained from the analysis of digital surface models produced in laboratory or relative to well known site. In particular advanced techniques for the study of 3D model and the detection and geometric characterization of forms are investigated.
Then we present some data acquired at high resolution (few centimeters) with a multibeam sonar mounted on a remote controlled vessel. Field surveys were conducted in real fluvial environment with the aim of produce qualitative and quantitative information about the surface layer of riverbed.
Even considering some sources of uncertainty that may be present from field survey to modeling, the obtained results show how it is possible to identify and geometrically characterize several of the forms present on the surfaces analyzed. 

How to cite: Rover, S., Avancini, G., and Vitti, A.: Management and analysis of high resolution multibeam sonar surveys for geometry characterization of riverbed material, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-981, https://doi.org/10.5194/egusphere-egu2020-981, 2020.

EGU2020-10187 | Displays | GI1.3

Time-SIFT : a frugal method for leveraging multi-temporal photogrammetric data without ancillary data

Denis Feurer, Sean Bemis, Guillaume Coulouma, Hatem Mabrouk, Sylvain Massuel, Romina Vanessa Barbosa, Yoann Thomas, Jérôme Ammann, and Fabrice Vinatier

Latest advances in lightweight aerial platforms, miniaturized RTK DGPS positioning and IMUs make now it possible to build multitemporal photogrammetric datasets with centrimetric accuracies. Together with the increase of very high-resolution topographic data availability, algorithms that came from the computer vision community also provoked a marked resurgence of interest on archival photogrammetric data. Recently, Feurer and Vinatier (2018) proposed a method that rely on the invariance properties of the feature detection algorithms such as SIFT to estimate orientations in a single multi-temporal block. This method allows for an inherent co-registration of processed multi-temporal photogrammetric datasets and hence detection and mapping of 3-D change from past imagery. This work demonstrated that – in the case of archival aerial imagery – the Time-SIFT method enables the processing of multi-temporal photogrammetric imagery without ancillary data.

However, the potential of the Time-SIFT method had to be checked for in various contexts and spatio-temporal scales. More, the Time-SIFT method may allow to cope with the lack of precise positioning, in the case of image acquisitions made with frugal acquisition systems for instance. Hence this study proposes to apply the Time-SIFT method on five contrasting test cases. Their time and space scales vary from a domain of several square-centimeters to domains of several tens of kilometers, with time spans varying from the minutes to the decades. The test cases rely within different disciplines of geosciences, from soil science to vulcanology. Our works showed that the Time-SIFT methods succeeds through this whole range of spatio-temporal scales, and show even some unexpected robustness in context of strong changes due to vegetation and/or presence of water in coastal areas. These results demonstrate that the Time-SIFT method has a potential to tackle a wide variety of multi-temporal photogrammetric datasets, in particular in contexts where additional and calibration data are scarce.

How to cite: Feurer, D., Bemis, S., Coulouma, G., Mabrouk, H., Massuel, S., Barbosa, R. V., Thomas, Y., Ammann, J., and Vinatier, F.: Time-SIFT : a frugal method for leveraging multi-temporal photogrammetric data without ancillary data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10187, https://doi.org/10.5194/egusphere-egu2020-10187, 2020.

EGU2020-1744 | Displays | GI1.3

UAS radiation hot-spot detection and refinement

Kieran Wood, Dean Connor, Sevda Groen, Dave Smith, Sam White, Peter Martin, Yannick Verbelen, Erin Holland, Tom Richardson, and To Scott

Unoccupied Aerial Systems (UAS) are ideal tools for responding to nuclear incidents where large outdoor areas have become contaminated with a radiological hazard. They are advantageous because rapid response radiation surveys can be conducted while the human operator remains at a safe distance and avoids direct contamination of the platform. During fieldwork within the Chernobyl Exclusion Zone (Ukraine), an airborne platform was equipped with a GNSS enabled gamma spectrometer and used to survey an area surrounding a known highly contaminated building (a ‘hot-spot’), resulting in a radiation intensity map. The detected radiation pattern, however, was ‘blurred’ since the intensity recorded at any point counted nadir emissions, but also emissions from all sources within line-of-sight; The ‘hot-spot’ had an influence far outside its ground footprint. Methods exist to correct for errors introduced by varying terrain altitude, however, they do not remove the unwanted blurring. Hence, small point sources appear as broad regions of contamination which is entirely an artefact of the measurement process. The effect is further accentuated with increasing height above ground hence understanding and correcting for this phenomenon is particularly relevant to data collected using UAS. Here, we present a novel algorithm to refine the detected pattern to more accurately recover the ground-truth.

A forward model of the system is created which describes the relationship between the unknown ground-truth and the aerial measurements. Gamma ray emissions from a point source obey the inverse square law of spatial dilution and have an exponential attenuation in air. To model both effects, geometric information of the scene is required and is provided by the geotagged spectrometer data and photogrammetrically processed DEMs of the surveyed terrain. The resulting model is hyper-cube of linear equations, where every aerial measurement point is assumed to be influenced by every ground sample point. By finding the inverse solution of this system, the ground-truth radiation pattern is estimated in more detail. The Kaczmarz method is advantageous because a large system of equations can be broken down into smaller sub-routines and solved iteratively. A caveat is that the solution might settle to false positive. The refinement algorithm will be presented with simulated results, controlled laboratory experiments using robotic arms and sealed radioactive sources, and finally applied to a real-world data set collected in the Chernobyl Exclusion Zone.

How to cite: Wood, K., Connor, D., Groen, S., Smith, D., White, S., Martin, P., Verbelen, Y., Holland, E., Richardson, T., and Scott, T.: UAS radiation hot-spot detection and refinement, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1744, https://doi.org/10.5194/egusphere-egu2020-1744, 2020.

EGU2020-3134 | Displays | GI1.3

Geomorphological response to volcanic activity at Stromboli volcano using multi-platform remote sensing

Federico Di Traglia, Alessandro Fornaciai, Massimiliano Favalli, Teresa Nolesini, and Nicola Casagli

Steep volcano flanks are geomorphological systems highly responsive to both exogenous dynamics and endogenous forcing. While the external (gravitational) processes lead to a shift of material from steeper slopes to areas with lower gradients (erosion of loose deposits, rockfall of lavas/welded material), magmatic and tectonic activity can have either a constructional (accumulation) or a destructive effect (triggering moderate- to large-scale mass-wasting). Remotely sensed data have often been used to map areas affected by lithological and morphological changes, i.e. to identify areas impacted by eruptive and post-eruptive (landslides or floods) phenomena, as well as to quantify topographic changes.

In this work, the geomorphological evolution of the Sciara del Fuoco (SdF) depression on the Island of Stromboli (Italy) between July 2010 and October 2019 has been reconstructed by using multi-temporal, multi-platform remote sensing data. Digital elevation models (DEMs) from PLEIADES-1 tri-stereo images and from LiDAR acquisitions allowed the topographic changes estimation. Data comprised also high-spatial-resolution (QUICKBIRD) and moderate spatial resolution (SENTINEL-2) satellite images allowing to map areas affected by major lithological and morphological changes. SdF was selected being the optimal test-site for monitoring the effect of volcanic eruption on steep-slope volcano flank, since: i) it is affected by persistent volcanic activity, ii) it is prone to mass-wasting phenomena, and iii) it is one of the best studied and, among all, monitored volcano on Earth, providing exceptional validation data and ground-truth constrains.

During the analysed period, the volcano experienced two eruptions (summer 2014 and summer 2019), with the emplacement of two lava flow fields on the SdF. Before the 2014 effusion and in between the two eruptions, geomorphological changes consisted of volcanoclastic sedimentation and some overflows outside the crater. The effusive (and partially explosive) activity produced larger topographic changes, related to the emplacement of the two lava flow fields and to the accumulation of a volcaniclastic wedge on the SdF. This work shows that, at Stromboli, the emplacements of lava flow fields were preceded and accompanied by the accumulation of volcanoclastic wedges on the SdF. The quantification of these volcanoclastic wedges is relevant because they are composed of the same material that was involved in the 30 December 2002 tsunamigenic landslide, besides being located in the same area.

PLEIADES tri-stereo and LiDAR DEMs have been quantitatively and qualitatively compared, providing a first indication on the differences between two largely used methods for modelling topography. Although there are small artefacts in smaller ridges and valleys, there is still a clear consistency between the two DEMs for the main valleys and ridges. This analysis can be used by the volcanological community and the civil protection authorities in case of a cost-benefit analysis for planning the best method for updating topography and quantify morphological changes of an active volcano.

How to cite: Di Traglia, F., Fornaciai, A., Favalli, M., Nolesini, T., and Casagli, N.: Geomorphological response to volcanic activity at Stromboli volcano using multi-platform remote sensing, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3134, https://doi.org/10.5194/egusphere-egu2020-3134, 2020.

EGU2020-3930 | Displays | GI1.3

Role of discontinuities in spatial pattern of sea cliff erosion: case of a seaward dipping flysch cliff (Socoa, Basque Country, France)

Vincent Regard, Melody Prémaillon, Thomas J. B. Dewez, Nick J. Rosser, and Sébastien Carretier

Sea cliff shapes and erosion rates are controlled by several factors. Among them, rock resistance, whose strength results from lithology and rock structure, are pointed as major factors. Erosion is expected to focus on discontinuities where the rock mass is weakest (faults, fractures, joints and strata bounds), but understanding the control of discontinuities on the spatial and temporal pattern of erosion remains challenging. To analyze and quantify how rock structures control erosion, we monitored the evolution of a 400-m-long stretch of well-structured sedimentary cliffs: the Socoa cliff (Basque Country, France). The rock, known as the Socoa flysch formation, is a 45°-seaward-tilted, shore-parallel-striking, decimeter-thick repeating sequence of sandstone, mudstone, marl and limestone beds. Cliff-face erosion was observed and quantified using 6 ground-based Structure-from-Motion (SfM) surveys, spanning 5.7 years between 2011 and 2017.  To compare with longer term data, a multi-decadal (54 years) cliff-top retreat rate was also assessed using SfM-orthorectified archive aerial photographs spanning the period 1954-2008. During the ground-based survey, the 13 250 m² cliff face released 4500 blocks larger than 1.45*10-3 m3 for a total rock volume eroded of 170 m3. This rock lost volume equates to an average cliff retreat rate of 3.4 mm/yr. It is slightly slower than the 54 years-average cliff top retreat rate of 10.8 ± 1.8 mm/yr. In elevation, the maximum erosive activity is positioned about 2 m above high spring tides. The geographic position of rock scars is controlled by tectonic discontinuities. Alongshore, hot-spots of erosion are focused where major faults cross-cut the cliff face. Around these geographic hotspots, the depth of detached blocks is controlled by bed thickness, removing one or several beds at once. The surficial extent of detached blocks on the cliff-face is controlled by orthogonal secondary tectonic joint sets. These joints do not stop on lithological bed limits but rather on mechanical limits encompassing several lithological beds at once. As a process, we explain block detachment and cliff collapse by a cycle of erosion nucleation on discontinuities, radial erosion propagation around the nuclei and finally, cliff collapse crisis affecting the cliff top. We demonstrate that block production is concentrated around faults (nucleation) that focus erosion and allows for the radial development of sea caves close to cliff foot. Then, block production occurs mainly around those caves by radial detachment processes at free edges or fractures (propagation). It may lead, exceptionally, to high-magnitude events, during which slab collapse can affect the cliff from base to top (crisis).

How to cite: Regard, V., Prémaillon, M., Dewez, T. J. B., Rosser, N. J., and Carretier, S.: Role of discontinuities in spatial pattern of sea cliff erosion: case of a seaward dipping flysch cliff (Socoa, Basque Country, France), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3930, https://doi.org/10.5194/egusphere-egu2020-3930, 2020.

EGU2020-19847 | Displays | GI1.3

Close-range sensing and object-based analysis of shallow landslides and erosion in grasslands

Andreas Mayr, Martin Rutzinger, Magnus Bremer, and Clemens Geitner

Close-range sensing methods for topographic data acquisition, such as Structure-from-Motion with multi-view stereo (SfM-MVS) photogrammetry and laser scanning from the ground or from unmanned aerial systems (UAS), have strongly improved over the last decade. As they are providing data with sub-decimetre resolution and accuracy, these methods open new possibilities for bridging the gap between local in-situ observations and area-wide space-borne or aerial remote sensing. For assessments of shallow landslides and erosion patches, which are wide-spread phenomena in mountain grasslands, the potential of close-range sensing is two-fold: Firstly, it could provide accurate reference data for assessing the geometric accuracy of a catchment or regional scale eroded area monitoring based on aerial or satellite remote sensing systems. Secondly, selected sites can be monitored at a very detailed local scale to reveal processes of secondary erosion or natural vegetation succession and slope stabilisation. Furthermore, high-resolution 4D data from multi-temporal close-range sensing make it possible to quantify volumes and rates of displacement at erosion features. In this contribution, we propose to exploit this potential of close-range sensing for landslide and erosion studies with object-based approaches for raster and 3D point cloud analyses. Assuming that erosion features can be discriminated from undisturbed grassland and from trees and shrubs, based on their morphometric and spectral signatures, we show how computer vision and machine learning techniques help to detect and label these features automatically as spatial objects in the data. We combine this object detection and labelling with 2.5D differential elevation models and with 3D deformation analysis of point clouds. This strategy addresses one of the key challenges of automatically analysing close-range sensing data in geomorphological studies, i.e. linking geometric information (such as the size and shape of erosion features or the surface change across a time series) with semantic information (e.g. separating vegetation from complex ground structures). In three case studies from recent projects in the Alps, where we acquired data by UAS, terrestrial laser scanning and terrestrial photogrammetry, we demonstrate the use of these new methodological developments. The methods tested can reliably detect changes with minimum magnitudes of centimetre to decimetre level, depending primarily on the specific data acquisition setup. By automatically relating these changes to erosion features of different scales (i.e. both at entire eroded areas and at their components, e.g. collapsing parts of the scarp), such analyses can provide valuable insights regarding process dynamics. In our tests, close-range sensing and automated data analysis workflows helped to understand both the development of new eroded areas as well as their enlargement by secondary erosion processes or episodic landslide reactivation. Based on the experience from these case studies, we also discuss the main challenges and limitations of these methods for erosion monitoring applications.

How to cite: Mayr, A., Rutzinger, M., Bremer, M., and Geitner, C.: Close-range sensing and object-based analysis of shallow landslides and erosion in grasslands, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19847, https://doi.org/10.5194/egusphere-egu2020-19847, 2020.

EGU2020-1382 | Displays | GI1.3

Particularities of the current geographical area of Suceava county in the period preceding the imperial occupation

Cristian Ciubotaru, Vasile Efros, and Liliana Daniela Diacon

    The situation of the geographical map of Europe in the time interval precursor of the imperial occupation in Bukovina, was fueled by the change of the balance of forces. Territorial entities with unstable administration, depending on an imperial structure, have constituted a currency of exchange due to agreements independent of the will of the indigenous population. The upper country of Moldova did not benefit from a consistent geographical research, the first territorial representations stopped at the Carpathian mountains as a natural border of the Central European world. The first maps of Moldova are studied with a focus towards the north of the territory, identifying settlements with economic importance in the future region of Bukovina. Cutting some geographical elements represents an interest for the territorial entity in which the cartographic projection is edited.

    The objectives of the paper are: 1) geographical analysis of northern Moldova during the period preceding the occupation of the Habsburg Empire, 2) identifying the degree of geodemographic and economic homogeneity of northern Moldova, and 3) research of natural geographical factors in determining the reasons of Bukovina’s annexation.

    The paper highlights the period prior to the occupation, identifying geographical data about the Upper Country of Moldova, cartographic transpositions, geodemographic characteristics, economic aspects, travel impressions. These combined elements identify the degree of territorial homogeneity between the future region of Bukovina and the geographical area remaining as the principality of Moldova. The natural potential of the northwestern region of Moldova is identified in comparison with the rest of the territory. The geographical causes of the annexation of the north of Moldova are analyzed, identifying aspects other than those of spatial continuity with Galicia, geopolitical and administrative elements. The natural setting can be an element of harmony with the imperial center as a motivation for the occupation of colonization and harmonious integration of ethnic minorities.

     The Carpathian Mountains have been a long-standing eastern border for the expansion of Central-European powers. Looking at an imperial map it is found that Bukovina is in the eastern extremity that cuts the territory of Moldova in the northwest. The natural geographical area of Bukovina is identified as a miniature Austria, a mountainous area in the west with wide depressions and boreal landscape, and in the east a flat plateau favorable to agricultural crops. The temperate-continental climate with Scandinavian-Baltic shades may play a role of interest for an Anglo-Saxon people adapted to this type of climate. ,,The country of  beeches", reflects a geographical landscape being predominantly identifiable in western and central Europe. Natural resources are more important in terms of value and quantity compared to other regions of Moldova that have not entered the imperial sphere.

     The conclusions also involve a research of the degree of natural attractiveness in the motivation of occupying the northwestern part of Moldova. The research methodology involves the transposition of historical information into geographic data, comparative analysis and cartographic method.

  

Keywords: Bukovina, Moldova, geography, contrast.

How to cite: Ciubotaru, C., Efros, V., and Diacon, L. D.: Particularities of the current geographical area of Suceava county in the period preceding the imperial occupation, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1382, https://doi.org/10.5194/egusphere-egu2020-1382, 2020.

EGU2020-8231 | Displays | GI1.3

Multi-decadal (1953 – 2017) response of rock glacier morphodynamics to climate change in the Kauner Valley in the Ötztaler Alps, Austria based on historical aerial images and airborne LiDAR data

Fabian Fleischer, Florian Haas, Tobias Heckmann, Moritz Altmann, Livia Piermattei, Jakob Rom, and Michael Becht

Although the observed global climate change has particularly affected high-alpine regions and these geosystems seem to react very sensitively to changes in external forcing, there is a lack of understanding about the effect of a changing climate upon high-alpine landscapes at the timescale of decades.  In the case of rock glaciers, which are common features in high alpine periglacial landscapes, numerous studies suggest a general acceleration of rock glacier displacement rates accompanied by surface lowering. This behaviour has been attributed to the rising permafrost temperature, induced by atmospheric warming and regulated by thermo-hydrological processes. On the other hand, decoupled kinematics of nearby rock glaciers under the same climatic forcing have also been proven. This is attributed to different local topo-climatic conditions and genesis of the investigated rock glaciers.  To contribute to the understanding of multi-decadal rock glacier response to climate change, we investigate the morphodynamic changes for selected rock glaciers in the Upper Kauner Valley in the Ötztaler Alps, Austria, a catchment comprising numerous rock glaciers of different size, genesis, elevation, aspect and activity status. This is done for multiple time slices between 1953 and 2017. These changes are analysed with respect to rock glacier characteristics and changes in the meteorological forcing. This work is part of the interdisciplinary and multi-university research project SEHAG (Sensitivity of high alpine geosystems to climate change since 1850), which aims to investigate changes in different processes of alpine geosystems and their interaction.

In order to investigate morphodynamics of the rock glaciers, we use digital photogrammetry to generate orthophotos and digital elevation models from historical aerial images (available since 1953). Additionally, we use digital elevation models generated from three airborne LiDAR surveys within the period 2006-2017. While the diachronic analysis of digital elevation models predominantly addresses vertical surface changes, image correlation of multitemporal digital orthophotos yields information on rates of horizontal displacement. The results for the individual rock glaciers are compared to each other and to meteorological data of nearby weather stations to analyse the response of rock glaciers with different characteristics to changing climate forcing. 

How to cite: Fleischer, F., Haas, F., Heckmann, T., Altmann, M., Piermattei, L., Rom, J., and Becht, M.: Multi-decadal (1953 – 2017) response of rock glacier morphodynamics to climate change in the Kauner Valley in the Ötztaler Alps, Austria based on historical aerial images and airborne LiDAR data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8231, https://doi.org/10.5194/egusphere-egu2020-8231, 2020.

EGU2020-11150 | Displays | GI1.3

An open-source toolset for automated processing of historic spy photos: sPyMicMac

Robert McNabb, Luc Girod, Christopher Nuth, and Andreas Kääb

First launched in 1971, the KH-9 “Hexagon” reconnaissance satellites were operational until 1986. In addition to the high-resolution main cameras, the satellites had a secondary camera system, the mapping camera, which acquired images at approximately 6-10m ground resolution. These images, declassified in 2002, provide an unparalleled ability to extend records of elevation change over areas of the world where older data, typically from aerial photogrammetry, are missing, unavailable, or unreliable, including High Mountain Asia and the Arctic. These images are not, however, free from challenges. Storage and film processing have introduced warping into the images, and the large film format means that images are scanned in halves which must be precisely re-aligned for photogrammetric processing.

 

Building on previous efforts, we have developed an open-source toolset, based in python, that performs several of the steps necessary for processing digital elevation models (DEMs) from the raw imagery within MicMac. These include precise re-alignment based on dense keypoint detection, automated detection of the reseau field to aid in un-warping of the images, color balancing to increase contrast in low-contrast areas, and automated detection of ground control points using modern orthorectified satellite images such as Sentinel-2 and Landsat 8, and high-resolution digital elevation models such as ArcticDEM. Each of these tools interface with the MicMac photogrammetry software package that performs each of the steps necessary for DEM extraction.

 

We have tested this toolset on scenes from Alaska, Iceland, and Norway. Comparison to external elevation datasets such as NASA’s Ice, Cloud and Elevation Satellite (ICESat), ArcticDEM, and national elevation products yields agreement of better than 10 m root mean square error over stable terrain, even in mountainous areas. In particular, we obtain satisfactory results in remote areas where precise ground control measurements are difficult to obtain. This toolset provides the ability to easily extend records of precise elevation change in areas where very little historic data exist. In addition, the GCP matching routine can be used to process other air photo datasets, providing a useful tool for processing older photo archives.

How to cite: McNabb, R., Girod, L., Nuth, C., and Kääb, A.: An open-source toolset for automated processing of historic spy photos: sPyMicMac, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11150, https://doi.org/10.5194/egusphere-egu2020-11150, 2020.

EGU2020-22558 | Displays | GI1.3

PyTrx: a Python-based monoscopic terrestrial photogrammetry toolset for glaciology

Penelope How, Nicholas Hulton, Lynne Buie, and Douglas Benn

Terrestrial photogrammetry is a growing method for deriving measurements from contemporary and historical imagery of glacial environments, providing unique insights into glacier change at a high spatio-temporal resolution. However, the potential usefulness of terrestrial image data is currently limited by the unavailability of user-friendly toolsets that contain all the photogrammetry processes required. PyTrx is presented here as a Python-alternative toolset to widen the range of monoscopic photogrammetry (i.e. from a single viewpoint) toolsets on offer to the glaciology community. The toolset holds core photogrammetric functions for template generation, feature-tracking, object identification, image registration, and georectification (using a planar projective transformation model), which can be performed on both contemporary and historical imagery. Examples of PyTrx's applications are demonstrated using contemporary time-lapse imagery, including ice flow velocities, surface areas of supraglacial lakes and meltwater plumes, and glacier terminus profiles.

How to cite: How, P., Hulton, N., Buie, L., and Benn, D.: PyTrx: a Python-based monoscopic terrestrial photogrammetry toolset for glaciology, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22558, https://doi.org/10.5194/egusphere-egu2020-22558, 2020.

EGU2020-7826 | Displays | GI1.3

Coupling historical maps and Lidar data to recognize man-made landforms in urban areas

Martino Terrone, Guido Paliaga, Pietro Piana, and Francesco Faccini

In the last years there is growing interest on urban geomorphology both for the links with landscape planning and for its historical, cultural and scientific interest.

The identification of landforms in urban contexts is particularly difficult due to the progressive stratification of urban phases: the foundation of cities in the Mediterranean area dates back to ancient times and their growth in size is generally significant from the Middle Ages. This makes it frequent to find landforms which date back to more than 1000 years ago: they can be new, man-made landforms or modifications of natural ones, particularly coastal or fluvial features. Land modifications are particularly significant in the last 2 centuries, notably in the second half of the C19th and in the second half of the C20th, two periods identified as the potential start of the Anthropocene.

Anthropogenic terrain features are generally due to excavation and fill: unlike natural landforms which are generally identifiable through field surveys, the former require field observations, cartographical comparisons, multitemporal comparison of topographical views and historical photographs, geognostic investigations and geophysical surveys.

This research presents the results of a multitemporal analysis of the city of Genoa carried out by superimposing data from nineteenth-century historical cartography and topographical data from Remote Sensing.  The 1:2.000 scale map of Ignazio Porro, dating back to the first half of the C19th, has been digitalised on Lidar images from 2019 and with 1 m resolution, provided by Genoa Municipality. This methodology, developed with QGIS, has been applied on 5 sample areas particularly significant for their anthropogenic modifications: the area around Sant’Agata bridge in Val Bisagno, the area of Morandi Bridge in Val Polcevera, the road called Circonvallazione a Monte, the Promontory of the Lighthouse and the Via Digione area. Through the overlaying of multitemporal cartographies it was possible to identify and quantify with great precision excavation, landfill and mixed areas, allowing the identification of the most significant anthropogenic landforms. The obtained results have been validated through direct observations and supported by data from the geognostic regional database, revealing the potential of this approach for other urban areas.

How to cite: Terrone, M., Paliaga, G., Piana, P., and Faccini, F.: Coupling historical maps and Lidar data to recognize man-made landforms in urban areas, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7826, https://doi.org/10.5194/egusphere-egu2020-7826, 2020.

EGU2020-22512 | Displays | GI1.3

Use of WWI photos for quantitative reconstructions of glaciers along the Italian-Austrian front

Luca Carturan, Aldino Bondesan, Alberto Carton, Federico Cazorzi, Sara Cucchiaro, Jessica De Marco, and Livia Piermattei

The knowledge of past fluctuations of glaciers is the key for understanding their dynamics and their climate-related evolution. Glacier mass balance and length changes are the two metrics normally used for reconstructing past fluctuations series of glaciers. However, length change measurements series are often discontinuous and require validation, whereas mass balance measurements are available for only a few glaciers worldwide and only for the latest decades.

In the context of glacier reconstructions, other sources of information such as historical-archival, glacio-archaeological and geomorphological data are of critical importance, because they enable the completion and validation of direct measurement series and their extension into the past, providing spatial and temporal constraints.

A unique source of unexploited historical information dating back to the First World War (WWI, 1915-1918) exists for many glaciers in the Eastern Italian Alps. This information mainly consists of old photos, which however are spread over a multitude of sources, often difficult to access, and in many cases not yet digitized.

We propose a workflow that enables extracting quantitative information from terrestrial photographs taken during the WWI period, aimed at the reconstruction of glacier area, volume and firn lines by means of the monoplotting technique. This method relies on the availability of high-resolution digital elevation models, which became recently available over wide areas thanks to LiDAR and aerial photogrammetry. This work presents the methods applied, and the results obtained, on several case studies in the Adamello-Presanella, Ortles-Cevedale, Dolomites, and Julian Alps.    

How to cite: Carturan, L., Bondesan, A., Carton, A., Cazorzi, F., Cucchiaro, S., De Marco, J., and Piermattei, L.: Use of WWI photos for quantitative reconstructions of glaciers along the Italian-Austrian front, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22512, https://doi.org/10.5194/egusphere-egu2020-22512, 2020.

EGU2020-22543 | Displays | GI1.3

Topographic maps – an important data source for investigating long-term glacier variations

Bettina Knoflach, Clemens Geitner, and Johann Stötter

The mountain cryosphere has been disproportionally affected by climate warming and changing precipitation conditions since the 19th century. This has caused intense and multiple reactions in high mountain hydrosphere, lithosphere, reliefsphere, biosphere and pedosphere. Although there is general knowledge on climate-related changes of glaciers, little is known about the high-resoluted temporal and spatial development of glaciers in the last century. These knowledge gaps further implicate limitations by simulating past and future development of the mountain cryosphere difficult, as important calibration and validation data are missing.

Topographic maps contain important information, as they are among the most reliable area-wide representations of past landscape for the time before airborne data acquisition. Thus, they offer the opportunity to extract former glacier extents and to close the information gap between the LIA extent, reconstructed from moraine extent, and aerial derived glacier information in the recent past.

However, as maps represent entities of a real world generalized depending e.g. on the intension of mapping, we consider map uncertainties as a crucial aspect for the reconstruction of glaciers from historical data.

In order to assess the accuracy of glacier area and front position from topographic maps, we reconstruct glacier extents under consideration of a comprehensive systematic examination of the uncertainty with regard to position, time and attribute. For this purpose, we use information of 12 topographic maps with a scale of 1:75,000 or larger from Kaunertal, covering a time span of 139 years (1871 – 2010) and analyse the accuracy of the maps focusing on production-related and transformation-oriented uncertainty.

The comparison between the glacier changes, derived from the maps and the original data (if available) as well as those measured in situ, shows that topographic maps are a reliable data source for the reconstruction of glacier front variations and provide vital key information when studying long time series.

How to cite: Knoflach, B., Geitner, C., and Stötter, J.: Topographic maps – an important data source for investigating long-term glacier variations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22543, https://doi.org/10.5194/egusphere-egu2020-22543, 2020.

EGU2020-22605 | Displays | GI1.3

Multi-temporal geomorphological maps based on historical aerial images for the investigation of geomorphic changes in an Alpine catchment

Tobias Heckmann, Livia Piermattei, Jakob Rom, Moritz Altmann, Fabian Fleischer, Florian Haas, and Michael Becht

Since the end of the Little Ice Age, alpine geosystems have been subject to changes due to the effects of ongoing climate change, affecting e.g. the cryosphere, topography, surface materials and morphodynamics, landcover, landuse, and other anthropogenic factors. Our work forms part of the SEHAG project that investigates the sensitivity of alpine geosystems to climate change during that period.

In order to identify and assess such changes, we aim at generating multi-temporal geomorphological maps of three alpine catchments (Upper Kaunertal, Horlachtal, Austria; Val Martello, Italy). In contrast to “traditional” geomorphological maps, we do not use areal, linear and point symbols to represent landforms, their properties, and geomorphic processes. Our approach is entirely based on non-overlapping polygon features that represent a landform- and process-centered subdivision of the catchment. This enables the analysis of the resulting map in a GIS framework with respect to the type, size and other properties of landforms. Most importantly, it allows for the assessment of their spatial configuration (adjacency, topology) within the catchment in terms of toposequences and sediment cascades.

Mapping is based on photogrammetric products of aerial photos, that are orthophotos, digital elevation models (DEMs) and derivatives of the latter. Furthermore, DEMs can be used for the orientation of historical terrestrial photographs, making them an additional mapping basis through monoplotting. Depending on the availability of imagery (area-wide aerial images dating back to the mid of the 20th century; local terrestrial photos starting from the second half of the 19th century), an area-wide geomorphological map representing the present state of the system forms the basis of our investigations. Historical images are then used to “update” the map back into the past wherever differences to the temporally subsequent situation are conspicuous. This especially regards the massive decline of glaciers, but also the build-up and depletion of storage landforms, the development of lakes, and changes in the channel network.

At a later stage, the maps will be used for a network-based, multitemporal assessment of sediment connectivity. Nodes represent landforms contained in the geomorphological map(s), and all kinds of evidence (visible features indicating sediment transfer between adjacent landforms, measurements based on DEMs of difference, connectivity indices) will be used to establish edges that represent (potential) sediment transfer by geomorphic processes. As the configuration of system components and/or the activity of processes changes between maps of subsequent epochs, these changes will affect connectivity measures of the corresponding network model.

How to cite: Heckmann, T., Piermattei, L., Rom, J., Altmann, M., Fleischer, F., Haas, F., and Becht, M.: Multi-temporal geomorphological maps based on historical aerial images for the investigation of geomorphic changes in an Alpine catchment , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22605, https://doi.org/10.5194/egusphere-egu2020-22605, 2020.

EGU2020-22519 | Displays | GI1.3

Between Land and Sea: An analysis of the landscape changes in the Chekka region (Lebanon) based on airborne LiDAR data and historical aerial images from 1962

Jakob Rom, Florian Haas, Manuel Stark, Andreas Poschenrieder, Karin Kopetzky, and Hermann Genz

The project “Between Land and Sea” was initiated by OREA (Institute for Oriental and European Archaeology) and is an interdisciplinary approach to combine the geology, geomorphology, and paleo-environment of the Chekka region (Lebanon) to investigate the ancient history and its archaeological remains. In the course of the project, the first ever scientific LiDAR (Light Detection and Ranging) data acquisition in Lebanon was conducted in autumn 2018 and a high-resolution DEM (Digital Elevation Model) was calculated. However, this model represents the recent topographical situation, which has changed drastically not only in the archaeologically relevant period up to 5000 years before today but also during the last decades.

To be able to qualitatively and quantitatively record geomorphological processes in the study area and thus understand long-term natural and anthropogenic landscape changes, the recent elevation model is compared with a historical model. The historical elevation model was derived on the base of aerial images of a French overflight from 1962. With the help of SfM (Structure from Motion/Agisoft Metashape) in combination with referencing methods (e.g. ICP), this historical model can be adapted to the LiDAR model. Quantitative analyses of selected areas provide information about surface changes over the last 56 years. But these results give also ideas about landscape evolution over longer time periods. Besides the natural changes, the historical model also reveals major anthropogenic changes since 1962 and shows that possible archaeologically relevant sites have been lost as a result of extensive overprinting due to the construction of buildings, infrastructure, industrial mining or agricultural use.

Our promising results show, that the implementation of historical terrain models based on aerial photographs can lead to a better understanding of the natural landscape development as well as anthropogenic induced changes and thus can also provide important additional information for archeological surveys.

How to cite: Rom, J., Haas, F., Stark, M., Poschenrieder, A., Kopetzky, K., and Genz, H.: Between Land and Sea: An analysis of the landscape changes in the Chekka region (Lebanon) based on airborne LiDAR data and historical aerial images from 1962, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22519, https://doi.org/10.5194/egusphere-egu2020-22519, 2020.

EGU2020-22544 | Displays | GI1.3

Multi-epoch bundle block adjustment for processing large dataset of historical aerial images

Camillo Ressl, Wilfried Karel, Livia Piermattei, Gerhard Puercher, Markus Hollaus, and Norbert Pfeifer

After World War II, aerial photography i.e. vertical or oblique high-resolution aerial images spread rapidly into civil research sectors, such as landscape studies, geologic maps, natural sciences, archaeology, and more. Applying photogrammetric techniques, two or more overlapping historical aerial images can be used to generate an orthophoto and a 3D point cloud, wherefrom a digital elevation model can be derived for the respective epoch. Combining results from different epochs, morphological processes and elevation changes of the surface caused by anthropogenic and natural factors can be assessed. Despite the unequalled potential of such data, their use is not yet fully exploited. Indeed, there is a lack of clear processing workflows applying either traditional photogrammetric techniques or structure from motion (SfM) with camera self-calibration. In fact, on the one hand, many SfM and multi-view stereo software do not deal with scanned images. On the other hand, traditional photogrammetric approaches require information such as a camera calibration protocol with fiducial mark positions. Furthermore, the quality of the generated products is strongly affected by the quality of the scanned images, in terms of the conservation of the original film, scanner resolution, and acquisition parameters like image overlap and flying height.

To process a large dataset of historical images, an approach based on multi-epoch bundle adjustment has been suggested recently.  The idea is to jointly orient the images of all epochs of a historical image dataset. This recent approach relies on the robustness of the scale-invariant feature transform (SIFT) algorithm to automatically detect common features between images of the time series located in stable areas. However, this approach cannot be applied to process digital images of alpine environments, characterized by continuous changes also of small magnitude that might be challenging to automatically identify in image space. In this respect, our method implemented in OrientAL, a software developed by TU Wien, identifies stable areas in object space across the entire time series. After the joint orientation of the multi-epoch aerial images, dense image matching is performed independently for each epoch. We tested our method on an image block over the alpine catchment Kaunertal (Austria), captured at nine different epochs with a time span of fifty years. Our method definitely speeds up the process of image orientation of the entire data set, since stable areas do not need to be masked manually in each image. Furthermore, we could improve the orientation of images from epochs with poor overlap. To estimate the improvements obtained with our methods in terms of time and accuracy of the image orientation, we compare our results with photogrammetric and commercial SfM software and we analyse the accuracy of tie points with respect to a reference Lidar point cloud. The work is part of the SEHAG project (project number I 4062) funded by the DFG and FWF.

How to cite: Ressl, C., Karel, W., Piermattei, L., Puercher, G., Hollaus, M., and Pfeifer, N.: Multi-epoch bundle block adjustment for processing large dataset of historical aerial images , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22544, https://doi.org/10.5194/egusphere-egu2020-22544, 2020.

EGU2020-2928 | Displays | GI1.3

Karst Topography Analysis Based on Multi-sensor (UAS & LiDAR) Data Acquisition

Aliki Konsolaki and Emmanuel Vassilakis

The state-of-the-art in surveying of open surface the last few decades is based on Point Cloud processing and interpretation. Lately, similar technology tends to be used for indoor surveying as well. One of the extreme applications is the use of the exact same technology in underground karstic cavities, evolving the methodology used in cave mapping. Geometric and morphometric analysis of the caves or any containing components (speleothems) include various techniques aiming at quantifying their dimensions in order to determine the characteristics and consequently the relationship between the cavity morphology and the surrounding structural, lithological and hydrogeological properties. The purpose of this research is to combine high resolution topographic data acquired with different instruments for both the underground morphology of a karstic cave (Koutouki, Peania, Greece) and the open-air surface above it. The described methodology is based on photogrammetric processing of Unmanned Aerial System image data and the extraction of a point cloud recorded with the use of a handheld laser scanning system. The latter resulted a 3D model of the cave and led to the production of a digital relief for the roof of the cave, which in turn was combined with the digital terrain model of the open-air surface above the cave. The final product is a high-resolution information layer with measurements of the rock thickness between the roof of the underground karstic structure and the open-surface topography with high accuracy.

How to cite: Konsolaki, A. and Vassilakis, E.: Karst Topography Analysis Based on Multi-sensor (UAS & LiDAR) Data Acquisition, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2928, https://doi.org/10.5194/egusphere-egu2020-2928, 2020.

EGU2020-18069 | Displays | GI1.3

Geomorphological and hydrological characterization of a meandering river by UAV and UWV applications

László Bertalan, Hannes Sardemann, David Mader, Noémi Mária Szopos, Bálint Nagy, and Anette Eltner

The Sajó River in Hungary is a medium-sized sand-bed river along which intensive meander development and bank erosion occur. The process threatens agricultural lands and populated areas extensively.  Therefore, preventive river management is needed.

Main geomorphological features, processes and in-channel flow conditions have to be studied in detail in order to reveal main driving factors. Datasets with high spatio-temporal resolution are necessary to identify relevant parameters. However, so far data density at this river is sparse and gauging stations are distributed poorly.

The aim of this study is the improvement of data availability to measure and model hydromorphodynamics of single reaches of the Sajó River. Therefore, multi-temporal field campaigns along selected sub-reaches are conducted with Unmanned Aerial Vehicles (UAV) and Unmanned Water Vehicles (UWV) to survey the topography, the river bed and flow conditions. The channel bathymetry is measured by a single-beam echo sounder mounted on a self-designed remotely controlled boat. The boat also integrates a Mobile Laser Scanner (MLS) to measure the river banks. Furthermore, a panorama camera system is installed to improve the pose estimation of the UWV functioning as a calibrated multi-sensor platform. UAV surveys were performed, using RGB and Thermal Infrared image sequences, to apply image velocimetry algorithms to characterize the river flow at selected cross-sections.  ADCP measurements and Terrestrial Laser Scans (TLS) are used for accuracy assessment of the novel datasets.

Eventually, data captured over a 2-years period will be implemented into hydrodynamic modeling of the studied sub-reaches to better understand seasonal variations in channel morphodynamics.

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The project has been founded by the DAAD (57448822) and (Tempus Public Foundation & DAAD 307670). The research is also influenced by the HARMONIOUS COST Action (CA16219).

How to cite: Bertalan, L., Sardemann, H., Mader, D., Szopos, N. M., Nagy, B., and Eltner, A.: Geomorphological and hydrological characterization of a meandering river by UAV and UWV applications, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18069, https://doi.org/10.5194/egusphere-egu2020-18069, 2020.

High resolution topographic models generated from repeat unmanned aerial vehicle (UAV) surveys and structure from motion (SfM) are increasingly being used to investigate landscape changes and geomorphic processes. Traditionally, accurate UAV surveys require the use of independently measured ground control points or highly accurate camera position measurements. However, in addition to accuracy in an absolute sense (how well modeled topography matches real topography), model quality can be expressed as accuracy in a comparative sense (the degree to which two models match each other). We present a simple SfM workflow for calculating pairs or sets of models with a high comparative accuracy, without the need for ground control points or a dGNSS equipped UAV. The method is based on the automated detection of common tie points in stable portions of the survey area and, compared to a standard SfM approach without ground control, reduces the level of change detection in our surveys from several meters to 10-15 cm. We apply this approach in a multi-year monitoring campaign of an 8 km stretch of coastal cliffs on the island of Rügen, Germany. We are able to detect numerous mass wasting events as well as bands of more diffuse erosion in chalk sections of the cliff. Both the cliff collapses and the diffuse erosion appear to be strongly influenced by antecedent precipitation over seasonal timescales, with much greater activity during the winter of 2017-2018, following an above average wet summer, than during the subsequent two winters, which both followed relatively dry summers. This points to the influence of subsurface water storage in modulating cliff erosion on Rügen.

How to cite: Cook, K. and Dietze, M.: UAV-derived change detection without ground control points, an example from the cliff coast of Rügen, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11735, https://doi.org/10.5194/egusphere-egu2020-11735, 2020.

EGU2020-3459 | Displays | GI1.3

Terrestrial-Aerial-SfM and TLS data fusion for agricultural terrace surveys in complex topographic and land cover conditions

Sara Cucchiaro, Daniel J. Fallu, He Zhang, Kevin Walsh, Kristof Van Oost, Antony G. Brown, and Paolo Tarolli

In the last two decades, important developments in High-Resolution Topographic (HRT) techniques, methods, sensors, and platforms has greatly improved our ability and opportunities for the characterization of landscapes through sub-metric DTMs (Digital Terrain Models). The choice of the most appropriate platform for HRT surveys must consider the required resolution, the spatial extent, and the features present in the analysed area. In complex topography, inaccessible areas and vegetated environments, the use of a single HRT technique is constrained by several factors. Therefore, data fusion from different acquisition platforms can be a useful solution if we design appropriate workflows for survey planning, data acquisition, post-processing, and uncertainty assessment. We tested this approach in the production of detailed DTMs of ancient agricultural terracing on two sites, Soave (North-east of Italy) and Martelberg in Saint-Martens-Voeren (East Belgium); case study sites for the TerrACE archaeological research project (ERC-2017-ADG: 787790, 2018-2023; https://www.terrace.no/). Both sites presented complex topographic and landcover conditions: the presence of vegetation (common in ancient, often abandoned, terraces) that cover parts of the sub-vertical surfaces (e.g., vertical walls of terraces), steep slopes and large survey areas. Therefore, we carefully designed the data fusion of HRT techniques in order to overcome all these constraints and thereby represent detailed 3D-views of the study sites. An integrated approach employing ground-based and UAV Structure from Motion (SfM) photogrammetry was used to preserve fine-grained topographic detail (via ground-based photos) and capture flat terrace zones at large spatial scale (via UAV images); while terrestrial Laser Scanner (TLS) permitted the accurate survey of the highly vegetated areas and vertical terrace walls. In order to create the point-cloud fusion, a key aspect for consideration when planning the survey planning was the location and distribution of the Ground Control Points (GCPs) for SfM and TLS targets. These are essential for georeferencing and co-registering of the aggregate data during the final merge. In the inaccessible zones of the studied areas, where was impossible to locate the GCPs, we tested the direct georeferencing of the UAV images with differential GNSS, such as PPK (post-processing kinematic). The SfM-TLS technologies allowed us to accurately recognize the topographic features of the entire terrace areas. This point-clouds merge was impossible to obtain without post-processing steps as co-registration process and uncertainty analysis. Even if several studies highlight how co-registration is essential in order to correctly merge HRT data, it is often not addressed in post-processing workflows. In this study, we demonstrated how survey planning and co-registration were fundamental phases for data fusion and allowed us to obtained proper and reliable DTMs. These high-resolution DTMs provided a high level of detail of landscape that was useful to extract valuable information about ancient terrace complexes: morphological features, profiles, sections and scaled plans, simplifying and speeding the archaeologist's field and laboratory work.

How to cite: Cucchiaro, S., Fallu, D. J., Zhang, H., Walsh, K., Van Oost, K., Brown, A. G., and Tarolli, P.: Terrestrial-Aerial-SfM and TLS data fusion for agricultural terrace surveys in complex topographic and land cover conditions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3459, https://doi.org/10.5194/egusphere-egu2020-3459, 2020.

A rock wall failure occurred along a major highway in south-eastern Norway, shutting down two lanes of traffic for an extended period of time while the road authority inspected and repaired the wall. It was desired to have a high-resolution digital surface model along a 215-m long section of the 34-m tall vertical rock wall that included the failure zone.

A Structure-from-Motion (SfM)-based methodology was selected to achieve the desired resolution on the rock wall face, as well as below the foot and above the head of the wall. Due to the proximity of the wall face to the remaining open lanes of traffic, it was not possible to survey the face of the wall using a remotely piloted aircraft system (RPAS). Therefore, a combined platform photogrammetric surveying technique was employed to ensure optimal photographic coverage and to generate the best possible model. Ground control points (GCP) were distributed and surveyed along the bottom and top of the wall and an RPAS was flown manually over the head of the wall to capture downward facing (nadir) images. A lift crane was also employed to capture images from elevations varying between 20–30 meters with a standoff distance of 15 meters from the wall. Finally, ground-based images were captured using a camera equipped with real-time GNSS from the top of the opposite rock wall (across the highway) with standoff distance of approximately 65 meters.

In total, over 800 images were ingested into a commercial SfM software package. The bundle adjustments were assisted by the GNSS-equipped camera locations and the surveyed GCP were imported to georeference the resulting model. The dense point cloud product was exported to a separate meshing software package for comparison with a second dense surface model that was derived from pre-existing images of the as-built condition of same rock wall face (prior to failure). By subtracting the post-failure model from the pre-failure model, a volume estimate of the material, that was mobilized during the failure, was determined.

The utility of the multi-platform survey technique was demonstrated. The combination of aerial and ground-based photographic surveying techniques provided optimal photographic coverage of the entire length of the rock wall to successfully derive high-resolution surface models and volume estimates.

 

 

Keywords: Structure-from-Motion, photogrammetry, digital surface model, natural hazards, ground control.

How to cite: Smebye, H., Salazar, S., and Lysdahl, A.: Combined aerial and ground-based Structure-from-Motion modelling for a vertical rock wall face to estimate volume of failure , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20471, https://doi.org/10.5194/egusphere-egu2020-20471, 2020.

EGU2020-4373 | Displays | GI1.3

Soil Water Content Variation Regression Analysis Using Hyperspectral Camera in Weathered Granite Soils

Hwan-hui Lim, Seung-Rae Lee, Enok Cheon, Deukhwan Lee, and Seungmin Lee

Soil water content is one of the most common physical parameters that cause landslides or debris flow. Therefore, it is of very importance to determine or predict the water content variation due to infiltration of rainfall quickly and non-destructively. This study investigates the hyperspectral informations in the visible near-infrared regions (VNIR, 400nm~1000nm) of different samples of granite soils possessing varying water contents. Totally 162 granite samples were taken from 3 mountain areas. A Partial Least Squares Regression (PLSR) analysis was applied to develop calibration models and prediction models.  In the water content variation prediction model, the Area of ​​Reflectance(Near-infrared, NIR) parameter was the most suitable parameter to determine the water content. The results demonstrate that the hyperspectral camera combined with the PLSR model can be a useful and non-destructive tool for the determination of soil water content variation in the weathered granite soils that could be applied to the evaluation of possible instable area in a mountain site.

How to cite: Lim, H., Lee, S.-R., Cheon, E., Lee, D., and Lee, S.: Soil Water Content Variation Regression Analysis Using Hyperspectral Camera in Weathered Granite Soils, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4373, https://doi.org/10.5194/egusphere-egu2020-4373, 2020.

Soil erosion represents one of the most significant environmental problems of the 21st century with severe impacts on terrestrial ecosystems. Traditionally, soil losses by water are determined by runoff plots in situ. Micro-scale devices (<1 m length) are commonly used to monitor soil erosion rates in comparative field studies. This is especially the case in ecological-pedological experiments, investigating e.g. the effect of plant characteristics on erosion processes. The small plot size allows to focus precisely on interrill processes with the smallest possible set of confounding factors and a high number of replications. However, the runoff plot method is labour- and time-intensive, sediment handling can be challenging and the measurement accuracy varies importantly with the applied control of the measurement setup.

To optimize the acquisition of small-scale erosion data from splash and interrill processes, digital methods become more and more of interest. Therefore, we compared the use of photogrammetry with a) terrestrial and b) airborne (UAV) single lens reflex (SLR) cameras as well as c) a terrestrial laser scanner (Leica Scanstation P40) to determine event-based initial erosion rates. Rainfall simulations with the Tübingen rainfall simulator and micro-scale runoff plots (0.4 m × 0.4 m) were conducted on two substrates: a Hortic Anthrosol and sieved sand (0.10-0.45 mm). Runoff plots were exposed to rainfall events with an intensity of 60 mm h-1. The measurements were repeated 5 times per substrate for each method and images of the runoff plot surfaces were captured before and after every event. The overlapping SLR images were processed in Agisoft PhotoScan (Structure from Motion - SfM) to process digital surface models (DSMs) with sub-millimetre resolution (a + b). Laser scans were processed with Leica Cyclone and ESRI ArcGIS (c). We assessed the volume of detached sediment by calculating the differences between multi-temporal DSMs or point clouds. After every rainfall simulation, the discharged sediment was weighed to derive the ground-truth for validation.

The results showed that photogrammetry with digital cameras as well as the use of laser scanners are principally suitable methods to create small-scale 3D point clouds and to map topography differences necessary for initial erosion rate calculation. The processing with common software systems, however, proves to be challenging and high precision is required for recording in the field. All methods overestimated the erosion rates with differences to the weighed sediment delivery from 14 to 45 %. The accuracy was higher for uniform sand than for the Anthrosol treatment. The SfM approach with digital cameras derived better results than the laser scanner used in this study. The terrestrial use of cameras was superior to the airborne use in this small-scale setup, because of the necessary flight altitude to avoid air turbulences on the soil surface. Further development of the measuring techniques and their precise application in the field as well as adapted software processing are still needed. Nevertheless, the methods tested show promising possibilities even for small-scale erosion measurements. Ideas and further suggestions on improvements will be presented at the EGU 2020.

How to cite: Seitz, S., Scholten, T., and Schmidt, K.: Soil erosion monitoring at small scales: Using close range photogrammetry and laser scanning to evaluate initial sediment delivery, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16685, https://doi.org/10.5194/egusphere-egu2020-16685, 2020.

EGU2020-18252 | Displays | GI1.3

High-resolution photogrammetric methods for nested parameterization and validation of a physical-based soil erosion model

Lea Epple, Andreas Kaiser, Marcus Schindewolf, and Anette Eltner

Soil erosion is one of the most prominent environmental problems of major interest to a vast field of research. Due to the complexity, variability and discontinuity of erosional processes, erosion model approaches are non-transferable to different spatial and temporal scales.

The objective of our project is the across-scale modelling of soil erosion, using photogrammetric measurements and optimization methods as well as physical based model approaches. Present process-based models are only valid for the observation scale they are parametrized and validated for. In the observed reality phenomena therefore occur, which are not or only to some extent reproducible by complex model concepts (e.g. development of rills or concentrated runoff within driving lanes). We present the synergetic combination of a physically described model with highly redundant observations from photogrammetric data processing. This enables both the validation of the erosion model EROSION-3D as well as the optimization of its parameters and potentially advancement of the mathematical process description. The photogrammetric observations (RGB and thermal) offer the opportunity of a temporal and spatial differentiated process assessment (splash, sheet and rill erosion, as well as deposition and transport). To this purpose, the acquisition of the respective operating processes and contributing factors, will be nested defined at three different scales (micro plot, single slope and catchment scale) on two sites (loess soil and residual soil).

Flexible cross-scale applicable photogrammetric methods, considering 3D reconstruction and flow measurement, combined with physical-based methods of soil erosion modelling shall enable a better and reliable understanding of soil erosion processes on various spatial and temporal observation scales. Consequently, the implementation of the adjusted model is aimed for to enable a cross-scale description and validation of scale-dependent processes (e.g. discrete consideration of thin sheet flow and rill genesis) to offer new perspectives on both interconnectivity of sediment transport and relationship between event frequency and magnitude.

How to cite: Epple, L., Kaiser, A., Schindewolf, M., and Eltner, A.: High-resolution photogrammetric methods for nested parameterization and validation of a physical-based soil erosion model, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18252, https://doi.org/10.5194/egusphere-egu2020-18252, 2020.

EGU2020-18742 | Displays | GI1.3

Improving the use of laser scanning intensity data in complex 3D mapping of the cave environment: Case study of the Gouffre Georges Cave, France

Michaela Nováková, Michal Gallay, Jozef Šupinský, Eric Ferré, and Patrick Sorriaux

Terrestrial laser scanning (TLS) is frequently used for contactless acquiring of highly detailed and accurate three-dimensional (3D) representation of natural landscapes and man-made objects. The advantage of TLS has been exploited in mapping the underground landscapes such as caves formed in various geological settings with variable dimensions extending from narrow passage to grand domes. Highly detailed cave surveying with TLS generates millions of 3D coordinates of cave surface by which mapping of features difficult to be reached and studied directly is possible, e.g. speleothems, ceiling channels, structural rock properties and rock type alongside with the tectonic features influencing overburden stability. Besides the 3D coordinates, intensity of the backscattered laser pulse is recorded in the form of an additional attribute, influenced by various factors including spectral properties of the surface material. The studies published on the use of laser intensity have been mainly focused on the correction of intensity recorded by TLS for objects in the above-ground environment, where atmospheric attenuation, specifically humidity or dust content in the air, is negligible or it is considered constant during scanning. However, caves are specific due to their complex morphology and aerosol in their atmosphere. The presented case study focuses on these aspects in correcting the recorded intensity with a long range TLS Riegl VZ-1000 in the Gouffre Georges cave which formed on the contact of marble and lherzolite in the French Pyrenees. We present complex workflow for elimination of the influencing factors associated with the scanning geometry, including range and incidence angle, taking into account the character and contours of the cave wall surface as a set of facets and effect of atmospheric attenuation. The resulting corrected intensity value depends mostly on the spectral surface properties. Derived reflectance values revealed different lithological layers allowing to analyse their lithological and structural properties. Corrected intensity can be also used in biospeleological studies for mapping and quantification of cave fauna, in speleology for observing structures with higher occurrence of wet areas where active karst processes occur and even in archaeological studies for identification of cave paintings.

How to cite: Nováková, M., Gallay, M., Šupinský, J., Ferré, E., and Sorriaux, P.: Improving the use of laser scanning intensity data in complex 3D mapping of the cave environment: Case study of the Gouffre Georges Cave, France, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18742, https://doi.org/10.5194/egusphere-egu2020-18742, 2020.

GI2.1 – Applications of data, methods and models in geosciences

EGU2020-1243 | Displays | GI2.1

Use of Digital and 3D Visualisation Technology in Planning for Woodland Expansion

Chen Wang, Alessandro Gimona, Andrea Baggio Compagnucci, and Yang Jiang

Forests and woodlands offer many benefits to people. They can provide timber and food, store carbon to help deal with the effects of climate change, decrease flooding and soil erosion, and provide recreation for people and habitat for a multitude of species we care to conserve. Scottish forests cover roughly 19% of the country. The Scottish government has the ambition to add several thousand hectares a year over the next decades, to support the rural economy, the environment, and communities. It is important that a substantial proportion of the expansion is made up by native trees and shrub species due to better habitat for wildlife.

These challenges were explored with a case study of virtual forest landscape from Cairngorms National Park (CNP) which was used to test preferences for scenarios of future woodland expansion. Spatial Multi-criteria Analysis (sMCA) has been applied to decide where to plant new forests and woodlands, recognizing a range of land-use objectives while acknowledging concerns about possible conflicts with other uses of the land. The tools used in the development and implementation of the 3D model were PC and Mobile based, and enable the incorporation of interactive functionality for manipulating features. Model inputs comprise 5m DTM, 25cm Aerial Imagery, 3D Tree Species, GIS layers of Current Forest and Woodland Expansion inside CNP. Afforestation animation has been attached in Google My Maps. This is through setting different keyframes by storyboard camera path animation around the area of CNP. Stereo panorama has been applied to selection of woodland expansion scenarios (e.g. Broadleaved potential corridors, Conifer potential corridors), which is viewed with mobile technology and Virtual Reality (VR) equipment.

The 3D model with simulation of woodland expansion was used at the event of 2019 Royal Highland Show and European Forest Institute Annual Conference 2019. Audience feedback suggested the enhancement of user interaction through VR has potential implications for the planning of future woodland to increase the effectiveness of their use and contribution to wider sustainable ecosystems.

How to cite: Wang, C., Gimona, A., Compagnucci, A. B., and Jiang, Y.: Use of Digital and 3D Visualisation Technology in Planning for Woodland Expansion, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1243, https://doi.org/10.5194/egusphere-egu2020-1243, 2020.

EGU2020-5132 | Displays | GI2.1

Three-dimensional geological mapping and modelling at the Geological survey of Sweden

Eva Wendelin, Mehrdad Bastani, Lena Persson, Phil Curtis, Daniel Sopher, and Johan Daniels

How to cite: Wendelin, E., Bastani, M., Persson, L., Curtis, P., Sopher, D., and Daniels, J.: Three-dimensional geological mapping and modelling at the Geological survey of Sweden, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5132, https://doi.org/10.5194/egusphere-egu2020-5132, 2020.

EGU2020-20777 | Displays | GI2.1

On the potential and challenges of using machine-learning for automated quality control of environmental sensor data

Lennart Schmidt, Hannes Mollenhauer, Corinna Rebmann, David Schäfer, Antje Claussnitzer, Thomas Schartner, and Jan Bumberger

With more and more data being gathered from environmental sensor networks, the importance of automated quality-control (QC) routines to provide usable data in near-real time is becoming increasingly apparent. Machine-learning (ML) algorithms exhibit a high potential to this respect as they are able to exploit the spatio-temporal relation of multiple sensors to identify anomalies while allowing for non-linear functional relations in the data. In this study, we evaluate the potential of ML for automated QC on two spatio-temporal datasets at different spatial scales: One is a dataset of atmospheric variables at 53 stations across Northern Germany. The second dataset contains timeseries of soil moisture and temperature at 40 sensors at a small-scale measurement plot.

Furthermore, we investigate strategies to tackle three challenges that are commonly present when applying ML for QC: 1) As sensors might drop out, the ML models have to be designed to be robust against missing values in the input data. We address this by comparing different data imputation methods, coupled with a binary representation of whether a value is missing or not. 2) Quality flags that mark erroneous data points to serve as ground truth for model training might not be available. And 3) There is no guarantee that the system under study is stationary, which might render the outputs of a trained model useless in the future. To address 2) and 3), we frame the problem both as a supervised and unsupervised learning problem. Here, the use of unsupervised ML-models can be beneficial as they do not require ground truth data and can thus be retrained more easily should the system be subject to significant changes. In this presentation, we discuss the performance, advantages and drawbacks of the proposed strategies to tackle the aforementioned challenges. Thus, we provide a starting point for researchers in the largely untouched field of ML application for automated quality control of environmental sensor data.

How to cite: Schmidt, L., Mollenhauer, H., Rebmann, C., Schäfer, D., Claussnitzer, A., Schartner, T., and Bumberger, J.: On the potential and challenges of using machine-learning for automated quality control of environmental sensor data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20777, https://doi.org/10.5194/egusphere-egu2020-20777, 2020.

EGU2020-9590 | Displays | GI2.1

A new tracking algorithm for cyclones with tropical characteristics in the Mediterranean basin

Enrique Pravia-Sarabia, Juan José Gómez-Navarro, Juan Pedro Montávez, and Pedro Jiménez-Guerrero
Given their potential to damage coastal zones, cyclones with tropical characteristics have been profoundly studied, although their genesis and development mechanisms are not fully established yet. Being less severe and shorter than their tropical counterparts, the so-called medicanes are storms within the mediterranean basin with certain tropical characteristics. One of the most important factors that determine the impacts of these tropical-like storms is their trajectory. Thus, the detection and tracking algorithms have been object of numerous studies since the origins of numerical weather prediction.
 
Due to their similarities with tropical cyclones, the same algorithms should in principle be suitable for these Mediterranean storms, even if some minor changes become necessary considering that they differ in size, duration and intensity. Despite these similarities, there seems to be no consensus on the best algorithm for medicanes tracking. Although some of the existing specific algorithms for tropical cyclones are of a very high spatial accuracy, there are some difficulties that need further assessment and discussion when applying them to medicanes, such as the existence of more intense non-tropical systems within the domain of study, the coexistence of multiple medicanes or interferences due to large orographic barriers. The development of specific medicanes detection and tracking algorithms is not an unspoiled matter and some methods have been developed for this purpose. Nevertheless, their applicability is limited when the aforementioned adversities come into play.
 
Our aim is to propose and evaluate a new algorithm specifically suited for medicanes tracking, flexible, robust and able to detect and track them even in the mentioned adverse conditions. This algorithm consists in the implementation of a time independent methodology allowing the automated detection of simultaneous tropical-like cyclones within the same domain. It also provides the possibility of an easy modification of the cyclone definition parameters to make it useful for the detection of different cyclone types. The computational efficiency and time-saving performance are key factors to take into account for the development of this algorithm. Consequently, it should also be suitable for medicanes climatological studies.

How to cite: Pravia-Sarabia, E., Gómez-Navarro, J. J., Montávez, J. P., and Jiménez-Guerrero, P.: A new tracking algorithm for cyclones with tropical characteristics in the Mediterranean basin, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9590, https://doi.org/10.5194/egusphere-egu2020-9590, 2020.

EGU2020-20333 | Displays | GI2.1

Combining hyperspectral and XRF analyses to reconstruct high-resolution past flood frequency from lake sediments

Kévin Jacq, William Rapuc, Anne-Lise Develle, Pierre Sabatier, Bernard Fanget, Didier Coquin, Maxime Debret, Bruno Wilhelm, and Fabien Arnaud

Due to global climate changes, an intensification of extreme events such as floods is expected in many regions, affecting an increasing number of people. An assessment of the flood frequencies is then a public concern. For several years now, numerous studies are undertaken on geological paleoclimate records and especially on lake sediments to understand the fluctuations of the flood activities in contrasting climatic contexts and over long time periods. Flood events produce turbidity currents in lake basins that will usually lead to a normal graded detrital layer that differs remarkably from the continuous sedimentation. Currently, in an overwhelming majority of studies, once identified, the layers with the same characteristics (e.g. texture, geochemical composition, grain-size) are usually counted by naked-eye observation. Unfortunately, this method is time-consuming, has a low spatial resolution potential and can lead to accuracy bias and misidentifications. To resolve these shortcomings, high-resolution analytical methods could be proposed, as X-ray computed tomography or hyperspectral imaging. When coupled with algorithms, hyperspectral imaging allows automatic identifications of these events.

Here, we propose a new method of flood layer identification and counting, based on the combination of two high-resolution techniques (hyperspectral imaging and high-resolution XRF core scanning). This approach was applied to one sediment core retrieved from the Lake Le Bourget (French Alps) in 2017. We use two hyperspectral sensors from the visible/near-infrared (VNIR, pixel size: 60 µm) and the short wave infrared (SWIR, pixel size: 200 µm) spectral ranges and several machine learning methods (decision tree and random forest, neural networks, and discriminant analysis) to extract instantaneous events sedimentary signal from continuous sedimentation. The study shows that the VNIR sensor is the optimal one to create robust classification models with an artificial neural network (prediction accuracy of 0.99). This first step allows the estimation of a classification map and then the reconstruction of a chronicle of the frequency and the thicknesses of the instantaneous event layers estimated.  

High-resolution XRF core scanning (XRF-CS) analyses were performed on the same core with a 200 µm step. Titanium (Ti) and Manganese (Mn) were selected as a high-resolution grain size indicator and a redox-sensitive element that shows abrupt inputs of oxygenated water-related to floods, respectively. Both elements have thus been added to the model in order to refine the chronicle derived from hyperspectral sensors. The combination of both hyperspectral and XRF-CS signal indicator allows to decipher floods from instantaneous deposits (e.g slump). This combined chronicle is in good agreement with the expected frequency obtained from the naked-eye chronicle realized on the same core (r² = 0.8). In this study, we present for the first time, an innovative approach based on machine learning which allows to propose fast automatized flood frequencies chronicles. This work was assessed by traditional deposits observations, but it can be easily applied to very micrometric deposits, undistinguishable to the naked eye. Finally, this model can be implemented with other indicators. It then represents a promising tool not only for flood reconstructions but also for other paleoenvironmental issues.

How to cite: Jacq, K., Rapuc, W., Develle, A.-L., Sabatier, P., Fanget, B., Coquin, D., Debret, M., Wilhelm, B., and Arnaud, F.: Combining hyperspectral and XRF analyses to reconstruct high-resolution past flood frequency from lake sediments, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20333, https://doi.org/10.5194/egusphere-egu2020-20333, 2020.

            Fuzzy modelling of multisource geoscience data and its implications to mineral prospectivity mapping is drawing wide attention of the mineral exploration sector. Mineral deposits are basically end products resulted from optimal combination of certain metallogenetically favourable earth processes which leave their imprints in the associated geological entities at a range of scales that can be interpreted from their direct or indirect manifestation in several geospatial datasets. Therefore, in geologically potential yet under-explored or greenfield areas with no or very few discovered mineral deposits, the qualitative knowledge on the spatial relationship between mineralisation of interest and geoscience data could be an important guide to delineate exploration targets. In such a case, fuzzy set theory aided with Geographic Information System (GIS) is preferred as an effective mechanism for the transformation of subjective knowledge into quantitative information that further helps in modelling of earth science data.

            The Archaean to Paleo-proterozoic Sonakhan Greenstone Belt (SGB) located in the north-eastern fringe of the Baster Craton in central India is considered as a potential geological terrane for mesothermal gold mineralisation based on its geological and geochemical similarities with other mineralised greenstone belts. In this case study, a part of SGB has been taken as a target area that exposes sequence of metamorphosed mafic to ultramafics rocks and associated metasedimentary units in a gneissic country and younger granites. Since the study area represents a less explored terrane in terms of mineralisation, the objective of this research is to generate gold prospectivity maps using fuzzy logic modelling. A total of 17 multiclass evidential maps were generated using four independent geoscience datasets viz. geological, geochemical, geophysical, and remote sensing. The sources of data include existing databases from the Geological Survey of India (GSI) and published work along with the newly produced exploratory data in this research. Fuzzy membership values (0-1) were assigned to each class of evidential maps based on subjective judgement. The fuzzyfied evidential maps were then combined using fuzzy operators (AND, OR, SUM, PRODUCT, and GAMMA) through a series of logical steps i.e. the fuzzy inference network. Two different fuzzy inference networks were created using several combinations of fuzzy operations and accordingly, two prospectivity maps resulted which were classified as very high, high, moderate, low, very low favourable zones. To further enhance the result, the two maps were intersected to produce the final gold prospectivity map in support of targeting gold exploration in the region. A part of the study area, that is the Baghmara gold block, that was already identified as a gold enriched block based on traditional exploration works, coincides with the very high to high favourable zones predicted in the final map and this ensures the reliability of the gold prospectivity map and the efficiency of the adopted fuzzy logic approach in delineating promising targets for exploration.

How to cite: Behera, S. and Panigrahi, M. K.: Application of various fuzzy inference networks to integrate mineral exploration datasets: Implication for gold prospectivity mapping in Sonakhan greenstone belt, India, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7576, https://doi.org/10.5194/egusphere-egu2020-7576, 2020.

EGU2020-21002 | Displays | GI2.1

UAV-based digital image processing applied to the fossiliferous tanks prospection: insights at Guanambi region, northeast Brazil

José Magalhães, Gessica Pereira, Alexsander Leão, and Carolina Scherer

This study reveals the use of high resolution images collected by small Unmanned Aerial Vehicle (UAV) and Digital Image Processing (DIP) from Structure from Motion (SfM) technique applied to the prospection and geometric characterization of fossil tanks in the Guanambi region, located at Bahia state, Brazil. Geologically, the region is located in the Guanambi Batolith, composed of granites, migmatites and orthognaisses. In the research region for example, there was the Lagoa das Abelhas fossiliferous tank, which was previously excavated and in which bone fragments of various pleistocene mammal taxa, such as those of the order Xenarthra, were found, represented by sloths, glyptodonts and armadillos. Considering that there are no records of an effective scientific method to identify these features, the main objective of this work is to map the distribution of fossiliferous tanks excavated as well as those with prospective potential, and to estimate the geometries that they present through the use of the high resolution DIP. The Phantom 4 Advanced equipped with RGB 1’’ CMOS effective 20 M sensor were the UAV model type and camera used for conducting the flight plan. The Pix4D Capture was the tablet/smartphone application used for conducting the flight operation and image collection in an area with ​​80 ha. After this step, the images were submitted as DIP routines using the SfM technique from the Agisoft Metashape software, version 1.5.1. The DIP is divided into stages like point cloud calculation, 3D models generation from mesh and texture procedures, digital elevation model (DEM) and orthomosaic. With the integration of images (DEM and orthomosaic) it was possible to identify and delineate a total of 14 targets through geometric information such as surface area, length, width, depth and internal format. The configuration in relation to soil type, vegetation and rock outcrops was the same around the Lagoa das Abelhas fossil tank. After that, the team came back to fieldwork and found fossil fragments of three out of fourteen targets. Thus, this study could show the potential of using UAV to cover large areas directed to the prospecting part of fossiliferous tanks with good flight autonomy, low cost and fast data analysis. Some of the 11 targets can be prospected because they have a high prospective potential due to their similarity to past prospects which became sites for future paleontological prospection.

How to cite: Magalhães, J., Pereira, G., Leão, A., and Scherer, C.: UAV-based digital image processing applied to the fossiliferous tanks prospection: insights at Guanambi region, northeast Brazil, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21002, https://doi.org/10.5194/egusphere-egu2020-21002, 2020.

EGU2020-1538 | Displays | GI2.1

Pattern recognition of Seismic Activity in Indonesia through Deep Learning

Nishtha Srivastava, Kai Zhou, Jan Steinheimer, Johannes Faber, and Horst Stoecker

Earthquakes have disastrously impacted communities by destructing the buildings and infrastructure and creating substantial setbacks in the socio-economic development of a region in addition to the huge human loss. They are inevitable and considered extremely difficult to predict. Earthquake prediction research is being carried out for more than 100 years with no well acknowledged model achieved till date. However, the analysis of past seismic stress history of an active fault may help in understanding the stress build up and the local breaking points of the faults. Yet, analysing and interpreting the abundant seismological dataset is most time consuming and is a herculean task.

The possibilities to solve big data, complex problems with Deep Learning are undeniable, however, it’s usage in Seismology is still in its early stage. The implementation of Deep Learning algorithms has the potential to decipher the complex patterns and hidden information in past stress history that is nearly impossible for scientists. The careful implementation of various Deep Learning algorithms in the exponentially growing seismic data can significantly improve the Early Warning System. In the present study, we train a time efficient machine/deep learning algorithm to self-learn and decode the intricate stress accumulation and release pattern, to estimate the probability of local breakdowns of the fault.

The study region for the present research is Indonesia, which under the influence of the Eurasian, Indo-Australian, Philippine and Pacific plates, immensely suffers due to high seismic activity. The principal contributor in the seismicity of the region is Java-Sunda Trench which lies in the Pacific Ring of Fire (PROF). Owing to the high frequency of earthquakes striking every year from different epicentres, the region provides a huge database. The earthquakes triggering in the region from 1970-2018 is downloaded from the International Seismological Centre website (http://www.isc.ac.uk). These earthquake data comprised of ~270,000 events with the information of Latitude, Longitude, Time of the event and focal depth. To respect the bias which is unavoidable due to the change of the quality of the sensors and the data over the decades, the data is divided into subsets. We considered both small and large magnitude earthquakes along the subduction line to generate a localized time series of stress release to understand the seismic history of the region. By using different neural network models such as one dimensional Convolutional Neural Network (CNN), Recurrent Neural Network (RNN), an optimized Deep Learning algorithm is trained to understand the intricate pattern associated with the seismic stress release in region. This specialized model is expected to empower seismologist by providing a time saving, automated process for the identification of the zone of failures.

How to cite: Srivastava, N., Zhou, K., Steinheimer, J., Faber, J., and Stoecker, H.: Pattern recognition of Seismic Activity in Indonesia through Deep Learning, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1538, https://doi.org/10.5194/egusphere-egu2020-1538, 2020.

EGU2020-148 | Displays | GI2.1

Integrated Geophysical study on the subsurface structural characterization of West Beni Suef area, Western Desert, Egypt

Ahmed Khalil, Ahmed El Emam, Tharwat Abdel Hafeez, Hassan Saleh, and Waheed Mohamed

The aim of this work is to study the subsurface structures in the west Beni Suef area of the Western Desert in Egypt and to determine their effects on surface geologic structures. A detailed land magnetic survey has been carried out for the total component of the geomagnetic field using two proton magnetometers. The necessary corrections concerning daily variation, the regional gradient and time variations have been applied. Then, the total magnetic intensity anomaly map (TMI) has been constructed and transformed to the reduced to the pole magnetic map (RTP). The reduction-to-pole magnetic and Bouguer anomaly maps were used to obtain regional extensions of this subsurface structure. Regional–residual separation is carried out using the power spectrum. Also, Edge detection techniques are applied to delineate the structure and hidden anomalies. Data analysis was performed using trend analysis, Euler deconvolution, the results indicate that the area is affected by tectonic forces in the N-S, NW-SE, NE-SW and E-W trends, which are correlated with the directions of surface geologic lineaments. In addition, depths to the basement rocks have been estimated using spectral analysis technique. The computed depths have been used to construct the basement relief map which resulted from gravity and magnetic data. They show that the depth to the basement rocks ranges from 2.3 km to 4.7 km.

KEYWORDS
Land magnetic, Gravity, Euler deconvolution, Edge detection and Spectral analysis.

How to cite: Khalil, A., El Emam, A., Abdel Hafeez, T., Saleh, H., and Mohamed, W.: Integrated Geophysical study on the subsurface structural characterization of West Beni Suef area, Western Desert, Egypt, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-148, https://doi.org/10.5194/egusphere-egu2020-148, 2020.

EGU2020-303 | Displays | GI2.1

Characterization of human behavior in records of personal solar ultraviolet exposure records

David Jean du Preez, Suzana Blesic, Caradee Y. Wright, Djordje Stratimirovic, Jelena Ajtic, Martin Allen, and Hassan Bencherif

We investigated scaling properties of measurements of personal exposure to solar ultraviolet radiation (pUVR) using the 2nd order detrended fluctuation analysis (DFA2) and the wavelet transform spectral analysis (WTS). Studies of pUVR are important to identify populations at-risk of excess and insufficient exposure given the negative and positive health impacts, respectively, of time spent in the sun. These very high frequency recordings are collected by electronic UVR dosimeters. We analyzed sun exposure patterns of school children in South Africa and construction workers and work site supervisors in New Zealand, and we found scaling behavior in all our data. The observed scaling changed from uncorrelated to long-range correlated with increasing duration of sun exposure. We found peaks in the WTS spectra that mark characteristic times in pUVR behavior, which may be connected to both human outside activity and natural (solar) daily cycles. We further hypothesized that the WT slope would be influenced by the duration of time that a person spends in continuum outside and addressed this hypothesis by using an experimental study approach. To that end we performed combined DFA2-WTS analysis on a subset of individual records taken on the same day under very similar outdoor conditions and used the theoretical superposition rule provided by systematic assessments of effects of trends and nonstationarities on DFA2 as a methodological mean to trace and subsequently model human behavioral patterns in pUVR time series.

How to cite: du Preez, D. J., Blesic, S., Wright, C. Y., Stratimirovic, D., Ajtic, J., Allen, M., and Bencherif, H.: Characterization of human behavior in records of personal solar ultraviolet exposure records, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-303, https://doi.org/10.5194/egusphere-egu2020-303, 2020.

EGU2020-4260 | Displays | GI2.1

Seismic attribute mapping of a fluvial reservoir in Rhourde Chegga field (Hassi Messaoud, Algeria)

Nasrine Medjdouba, zahia benaissa, and amar boudella

Rhourde Chegga field is located in the north of Hassi Messaoud giant field, Algeria. The main hydrocarbon-bearing reservoir in Rhourde Chegga field is the lower Triassic Argilo-Gréseux reservoir. The Triassic sand is deposited as fluvial channels and overbank sands with a thickness ranging from 15 to 20 m, lying unconformably on the Paleozoic formations. Lateral and vertical distribution of the sand bodies makes their mapping very difficult and, sometimes, even impossible with conventional seismic interpretation. 

To better define drilling targets within the Triassic sand in the Rhourde Chegga field, 3D stratigraphic seismic attribute analysis was performed along the reservoir level, using PSTM and mid angle stack seismic data. By combining various attributes (RMS amplitude, half energy, variance, etc.), the channelized feature has been clearly imaged and delineated on the horizon slices and the volume extraction. The relationship between the combined seismic attributes and reservoir properties at well locations showed a good correlation.

Based on this study, about ten produced wells have been successfully drilled, confirming the efficiency of seismic attribute analysis to predicted channel body geometry.

Keywords: Channel, Attributes, Amplitude, Fluvial reservoir.

 

How to cite: Medjdouba, N., benaissa, Z., and boudella, A.: Seismic attribute mapping of a fluvial reservoir in Rhourde Chegga field (Hassi Messaoud, Algeria), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4260, https://doi.org/10.5194/egusphere-egu2020-4260, 2020.

Geochemical anomalies are an important indicator in prospecting. In particular, geochemical anomalies of Cu play a very important role in geological prospecting of minerals. Geochemical anomalies of Cu are mainly related to mafic-ultramafic rocks and porphyry bodies, which are also associated with ore-forming elements of the Co-Zn-Cr-Ni-Cu combination. The conventional technique of geochemical prospecting involves superimposition of element symbols (Au, Fe, Cu, Al, Ca, etc.) on the geological map of an area by analysing geochemical anomalies using geochemical data. However, this technique is not suitable for regions where geochemical anomaly data are limited. The development of hyperspectral remote sensing has enabled the mapping of spectral features related to characteristic absorption bands of elements in minerals at high spatial resolution, providing a means for precise and detailed reconstructions of geochemical anomalies facies (surface). Compared to conventional techniques for identifying elements, reflectance spectroscopy offers a rapid, inexpensive, and non-destructive tool for determining the mineralogy of rock and soil samples. Hyperspectral remote sensing also provides data for prospecting in areas without sufficient geochemical data, and thus is of vital significance in prospecting for ores in such regions. However, approaches for remotely sensing elements are still lacking, particularly for element content. In this study, a level analysis of Cu content via spectral indices in the northwestern Junggar region, Xinjiang, was conducted. Based on four levels (0–100 ppm, 100–1000 ppm, 1000–10000 ppm, and >10000 ppm) of Cu content and corresponding spectral reflectance, simple and useful spectral indices for estimating Cu content at different levels were explored. The best wavelength domains for a given type of index were determined from four types of spectral indices by screening all combinations using correlation analysis. The coefficient of determination (R2) for Cu was calculated for all indices derived from the spectra of rock samples and was found to range from 0.02–0.75. With sensitive wavelengths and a significant correlation coefficient (R2 = 0.63, P < 0.005), the Normalized Difference (ND)-type index was the most sensitive to Cu content exceeding 10000 ppm. Although the ND-type index has a few limitations, it is a useful, simple, and robust indicator for determining Cu at high concentrations. With the advent of new platforms and satellites in the future, such relationships with other elements are required to enable the widespread use of this index in broad-scale surveys of mineral elements in the field.

How to cite: Shanshan, W. and Kefa, Z.: Study on the Geochemical Anomaly of Copper Element Based on Hyperspectral Indices, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6433, https://doi.org/10.5194/egusphere-egu2020-6433, 2020.

EGU2020-6503 | Displays | GI2.1

Estimation and validation of electric power output from a fixed-type floating photovoltaic system

Jangwon Suh, Sungmin Kim, and Yosoon Choi

An accurate estimation of electric power production (EPP) is a crucial first step to design a floating photovoltaics (PV) project. This study estimates the EPP of a floating PV system and validates the results by comparing with the actual EPP observed at the Hapcheon Dam, Korea. Typical meteorological year data and system design parameters were entered into System Advisor Model (SAM) software to estimate the hourly and monthly EPPs. Three-year average observed EPPs (2012, 2013, and 2015) were used as reference values for the validation. The results showed the seasonal EPPs were the highest in spring and the lowest in winter. The monthly estimated EPPs were lower than the monthly observed EPPs. These results are ascribed to the fact the SAM was unable to consider the natural cooling effect of the water environment on the PV module. The error results showed it was possible to estimate the monthly EPPs with an error of less than 15% simply by simulation. However, it may possible to estimate the monthly EPPs with an error of approximately 9% when considering empirical results: The floating PV efficiency was approximately 1.1 times (110%) the overland PV efficiency. This indicates that the approach of using empirical results can provide reliable monthly estimation of EPP in feasibility assessment stage of floating PV projects.

How to cite: Suh, J., Kim, S., and Choi, Y.: Estimation and validation of electric power output from a fixed-type floating photovoltaic system, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6503, https://doi.org/10.5194/egusphere-egu2020-6503, 2020.

Combining multi-source data can improve the accuracy and the spatial resolution of the three-dimensional (3-D) displacements field. How to effectively integrate multi-source data to obtain high-precision and high spatial resolution 3-D displacements field is worthy of further study. The stochastic model and fusion model of integrating multi-source data affect the accuracy of data fusion. In this paper, based on the least squares method, the effects of different stochastic models and data fusion models on the 3-D displacements field’s accuracy are studied. The optimal method for estimating large-scale 3-D displacements field from integrated InSAR, leveling and GPS measurements is obtained. Then we realize the integrating InSAR, leveling and GPS measurements to obtain the high-precision 3-D displacements velocity field in Tianjin(China) from 2016 to 2018. The results are validated with GPS measurements at 6 independent stations, with the root mean squares (RMS) residuals of the discrepancies being 2.39mm/yr、2.54mm/yr and 2.83mm/yr in eastern, northern and vertical directions, respectively. By comparing different stochastic models, the 3-D displacements field obtained from multi-source data is optimized by the variance component estimation-least squares method, which is better than weighted least squares (WLS) method. By comparing different data fusion models, the accuracy of the horizontal displacements velocity is better than that of interpolated GPS results. The horizontal displacements component has a great influence on the vertical displacements velocity accuracy in the process of acquiring the 3-D displacements velocity by integrating InSAR, GPS and leveling measurements. This study provides a reference method for integrating multi-source data to obtain 3-D displacements field. This method effectively utilizes the advantages of GPS, InSAR and leveling measurements, and extends the limitations of single technical in describing surface-time scale applications. The 3-D displacements information with a large spatial scale and high spatial resolution provide a reliable data basis for studying the crustal movement and its dynamic mechanism.

How to cite: Guo, N.: Influence of Different Data Fusion Methods on the Accuracy of Three-Dimensional Displacements Field , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6601, https://doi.org/10.5194/egusphere-egu2020-6601, 2020.

EGU2020-7204 | Displays | GI2.1

3D geological models from combined interpretation of airborne-TEM and geological data- Two examples from Sweden

Mehrdad Bastani, Lena Persson, Peter Dahlqvist, Eva Wendelin, and Johan Daniels

The geological survey of Sweden (SGU) has carried out several detailed airborne TEM (Transient Electromagnetic) surveys in recent years. The data collected in these surveys were inverted to provide models of the resistivity of the subsurface, down to a few hundred meters depth. These resistivity models together with the data from existing boreholes and ground observations offer an excellent basis for further 3D geological modeling. 

The airborne TEM data presented in this study were collected between 2013 and 2016, covering large areas of the islands of Öland and Gotland, in Sweden. Both islands face problems with water supply due to limited groundwater resources. The aim of the surveys was to identify new groundwater resources, specify the depth to saline groundwater and to improve the understanding of the geology of the islands. On Öland, the Paleozoic sedimentary succession reaches thicknesses of approximately 250 m and is composed of Lower Cambrian sandstone, Middle Cambrian siltstone, and claystone followed by the Alum Shales of Upper Cambrian and Lower Ordovician age. Above this lies an up to 40 m thick Lower Ordovician limestone succession, which forms the bedrock at the surface across much of the island. The entire sedimentary sequence rests on Precambrian crystalline rocks. On the Island of Gotland, Silurian bedrock represents the upper part of a 250-800 m thick Paleozoic sequence overlying the crystalline basement. The Silurian bedrock is dominated by interbedded layers of limestone and marlstone, where the interface between limestone and marlstone is often the primary hydraulic conductor.

After acquisition, these data were processed and inverted (1D inversions with lateral constraints), to provide a series of large airborne datasets, providing a resistivity image down to depths of about 250 m in some areas. The considerable resistivity contrast between lithologies, e.g. limestone and marlstone on Gotland, provided an excellent opportunity to resolve boundaries between the different rock types. Borehole information, geological maps, ground geophysical data and the inversion results were incorporated in a 3D geological modelling software. On comparison of the airborne models, ground geophysical data and borehole information it was clear that the airborne resistivity models correlated well with the other available data. Hence, the resistivity models were used as the basis for constructing the 3D hydrogeological and geological models over significant parts of the islands. In this study we present the 3D geological models over the islands of Öland and Gotland which were constructed from the integrated interpretation of all the available data. The models are composed of voxels, each representing a certain lithology classified using a statistical approach. The classification is based on the resistivity range, distance to the neighboring wells/boreholes and the geological observations at the surface. The 3D voxel models will be/have been utilized in hydrological modelling, societal planning, and groundwater management.

How to cite: Bastani, M., Persson, L., Dahlqvist, P., Wendelin, E., and Daniels, J.: 3D geological models from combined interpretation of airborne-TEM and geological data- Two examples from Sweden, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7204, https://doi.org/10.5194/egusphere-egu2020-7204, 2020.

EGU2020-7516 | Displays | GI2.1

3D geological model of the Gråbo site from ground TEM measurements

Daniel Sopher, Eva Wendelin, Lars-Ove Lång, Johan Öhman, and Andreas Lindhe

A 3D geological model was constructed for the Gråbo site to investigate its suitability for artificial groundwater infiltration, to provide drinking water. The modelling work was performed by the Geological Survey of Sweden (SGU) as part of ongoing groundwater investigations. The site is located close to the city of Gothenburg, in western Sweden. A relatively thick succession of coarse-grained glaciofluvial sediment is located at the site, which overlies a typically finer grained and more clay rich sequence. Previously, the site has been the target of several investigations, the most extensive of these was performed in 2006, where a range of geophysical (seismic refraction, ground penetrating radar and resistivity) and borehole measurements were conducted. Based on previous studies the upper course-grained layer has the best potential for infiltration. However, although these investigations improved the understanding of the site, significant uncertainty remained as to the geometry of the upper course grained layer away from borehole locations.

In order to improve the understanding of the site, additional data was collected in 2018 using a tTEM (towed transient electromagnetic) system developed by Aarhus university. The system is comprised of a transmitter and receiver coil, which are towed behind an ATV (all terrain vehicle). Using the tTEM data a 3D resistivity model of the subsurface was generated down to a depth of between 50 and 70 m at the Gråbo site. On comparison with the available borehole data, it was clear that the course-grained layer could be mapped with relatively high accuracy as a region of high resistivity. The tTEM data was combined with the pre-existing geophysical and borehole data to construct both a voxel and layer-based model of the site. These 3D models have subsequently been used as part of ongoing efforts to evaluate the suitability of the site for infiltration (for example, to decide the location of additional investigation boreholes and to provide input to hydrogeological modelling). In this study we present the tTEM data and the 3D geological model. Finally, we exemplify how the 3D model has been used in subsequent investigations and decision making.

How to cite: Sopher, D., Wendelin, E., Lång, L.-O., Öhman, J., and Lindhe, A.: 3D geological model of the Gråbo site from ground TEM measurements, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7516, https://doi.org/10.5194/egusphere-egu2020-7516, 2020.

EGU2020-8383 | Displays | GI2.1

IGMAS+ – a tool for interdisciplinary 3D potential field modelling of complex geological structures.

Sabine Schmidt, Denis Anikiev, Hans-Jürgen Götze, Àngela Gomez Garcia, Maria Laura Gomez Dacal, Christian Meeßen, Christian Plonka, Constanza Rodriguez Piceda, Cameron Spooner, and Magdalena Scheck-Wenderoth

We introduce a new approach for 3D joint inversion of potential fields and its derivatives under the condition of constraining data and information. The interactive 3D gravity and magnetic application IGMAS (Interactive Gravity and Magnetic Application System) has been around for more than 30 years, initially developed on a mainframe and then transferred to the first DOS PCs, before it was adapted to Linux in the ’90s and finally implemented as a cross-platform Java application with GUI called IGMAS+. The software has proven to be very fast, accurate and easy to use once a model has been established. Since 2019 IGMAS+ has been maintained and developed in the Helmholtz Centre Potsdam – GFZ German Research Centre by the staff of Section 4.5 – Basin Modelling and ID2 – eScience Centre.

The analytical solution of the volume integral for the gravity and magnetic effect of a homogeneous body is based on the reduction of the three-folded integral to an integral over the bounding polyhedrons (in IGMAS polyhedrons are built by triangles). Later the algorithm has been extended to cover all elements of the gravity tensor as well. Optimized storage enables very fast inversion of densities and changes to the model geometry and this flexibility makes geometry changes easy. The geometry is updated and the gravity is recalculated immediately after each change. Because of the triangular model structure, IGMAS can handle complex structures (multi Z surfaces) like the overhangs of salt domes very well. Geophysical investigations may cover huge areas of several thousand square kilometers but also models of Applied Geophysics at a meter scale. Due to the curvature of the Earth, the use of spherical geometries and calculations is necessary.

The model technique is user-friendly because it is highly interactive, operates ideally in real-time whilst conserving topology and can be used for both flat (regional) and spherical models (global) in 3D. Modeling is constrained by seismic and structural input from independent data sources and is essential toward true integration of 3D thermal modeling or even Full Waveform Inversion. We are close to the demand for treating all geophysical methods in a single model of the subsurface and aim of fulfilling most of the constraints: measurements and geological plausibility.

We demonstrate the flexibility of the software by modeling: (1) the southern segment of the Central Andes which is designed to assess the relationship between the characteristics of the overriding plate and the deformation and dynamics of the subduction system; (2) the South Caribbean margin which defines the two flat-slab subductions of the Nazca Plate and the Caribbean Plate, with variable mantle density distribution implemented by voxels; (3) the North Patagonian Massif Plateau in Argentina which provides insight into the main height differences between the plateau and the surroundings; and (4) an Alpine model which interrogates the strength of the lithosphere at different locations through the Alps and their forelands.

How to cite: Schmidt, S., Anikiev, D., Götze, H.-J., Gomez Garcia, À., Gomez Dacal, M. L., Meeßen, C., Plonka, C., Rodriguez Piceda, C., Spooner, C., and Scheck-Wenderoth, M.: IGMAS+ – a tool for interdisciplinary 3D potential field modelling of complex geological structures., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8383, https://doi.org/10.5194/egusphere-egu2020-8383, 2020.

EGU2020-12546 | Displays | GI2.1

Application of multi-sensor unmanned aerial system for identification of hydrothermal alteration zones

Yosoon Choi, Jieun Baek, Jangwon Suh, and Sung-Min Kim

In this study, we proposed a method to utilize a multi-sensor Unmanned Aerial System (UAS) for exploration of hydrothermal alteration zones. This study selected an area (10m × 20m) composed mainly of the andesite and located on the coast, with wide outcrops and well-developed structural and mineralization elements. Multi-sensor (visible, multispectral, thermal, magnetic) data were acquired in the study area using UAS, and were studied using machine learning techniques. For utilizing the machine learning techniques, we applied the stratified random method to sample 1000 training data in the hydrothermal zone and 1000 training data in the non-hydrothermal zone identified through the field survey. The 2000 training data sets created for supervised learning were first classified into 1500 for training and 500 for testing. Then, 1500 for training were classified into 1200 for training and 300 for validation. The training and validation data for machine learning were generated in five sets to enable cross-validation. Five types of machine learning techniques were applied to the training data sets: k-Nearest Neighbors (k-NN), Decision Tree (DT), Random Forest (RF), Support Vector Machine (SVM), and Deep Neural Network (DNN). As a result of integrated analysis of multi-sensor data using five types of machine learning techniques, RF and SVM techniques showed high classification accuracy of about 90%. Moreover, performing integrated analysis using multi-sensor data showed relatively higher classification accuracy in all five machine learning techniques than analyzing magnetic sensing data or single optical sensing data only.

How to cite: Choi, Y., Baek, J., Suh, J., and Kim, S.-M.: Application of multi-sensor unmanned aerial system for identification of hydrothermal alteration zones, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12546, https://doi.org/10.5194/egusphere-egu2020-12546, 2020.

Nowadays, powerful hand-held devices, like smartphones, tablets and smartwatches, are ordinary things, which many people take anywhere they go. One of the major advantages of this technology is the ability to locate its user by means of GNSS or cellular positioning. Paired with popular, free mobile mapping applications, it greatly simplifies the problem of finding oneself in the unknown place, calculating the best route to one’s destination by various means of transport or tracking one’s movement. For this reason, outdoor navigation is a well-established and widespread technology. The problem arises, when positioning and wayfinding are needed in a GNSS-denied environment, e.g. a building or a mine. In a complex, large or multi-floor constructions modern techniques for easing the navigation through them are rarely applied. Recent years brought numerous new, promising approaches and algorithms for solving a problem of indoor positioning and navigation, but many of them can’t be easily implemented on a typical smartphone or conveniently used. This includes Simultaneous Localization and Mapping (SLAM) and algorithms based on Augmented Reality (AR). It seems that the most feasible and cost-efficient methods are those based on Wi-Fi Access Point (AP), low-cost Bluetooth Low Energy (BLE) or Ultra-Wideband (UWB) beacons. This research aims to describe the process of developing such an Indoor Positioning and Navigation System in one of the buildings, located on the campus of the Wroclaw University of Science and Technology, and identify the main challenges that have to be overcome during this process. Feasibility of available GIS software solutions for this application is analyzed. Directions for future research and development are discussed.

How to cite: Trybała, P.: Development of an Indoor Positioning and Navigation System using Wi-Fi network and BLE beacons for the Smart Campus: A case study, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13858, https://doi.org/10.5194/egusphere-egu2020-13858, 2020.

EGU2020-14447 | Displays | GI2.1

Morphology and sedimentary filling of an ancient estuarine valley in an urban environment (Gijón, NW Spain)

Luis Pando, Germán Flor-Blanco, Jorge Rey Díaz de Rada, and Adrián García-Rodríguez

The city of Gijón is located on the Cantabrian Coast (NW, Spain), and its subsurface is formed mainly by sand linked to an old estuarine mouth barrier (beach and dunes), sand bay and marshes. Under these sediments, there is a layer of clays related to the weathering of a Jurassic rock basement. This research addresses the setting of the estuary sediments in both the submerged area, located north of the city, and under the built-up area.

The seafloor morphology was investigated by means of a bathymetric survey with multi-beam echo sounder. A geophysical survey using high-resolution reflection seismic profiles allowed studying the thickness of the unconsolidated deposits that fill the bay of Gijón. Likewise, the distribution of coastal sediments under the city was reviewed from boreholes collected within a GIS-based geotechnical database.

The bathymetric reconstruction led to the identification of a paleo-valley supposedly excavated by the main river of the city, with N-S orientation that evolves to NNE-SSW towards the north. It shows a sandy bottom with a very low slope, a length of about 4 km and a width that ranges between 400 and 800 m. In this channel, the unconsolidated deposits reach a maximum thickness of around 15 m while at S, in the urban subsurface, the thickness exceeds 20 m locally. With these data, it was also possible to investigate the geometry of the bedrock under the sedimentary filling.

How to cite: Pando, L., Flor-Blanco, G., Rey Díaz de Rada, J., and García-Rodríguez, A.: Morphology and sedimentary filling of an ancient estuarine valley in an urban environment (Gijón, NW Spain), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14447, https://doi.org/10.5194/egusphere-egu2020-14447, 2020.

EGU2020-20444 | Displays | GI2.1

Compositional data analysis of sedimentological, mineralogical and geochemical data for the evaluation of Austrian loess and loess loam deposits

Heinz Reitner, Christian Benold, Peter Filzmoser, Maria Heinrich, Gerhard Hobiger, Can Mert, Julia Rabeder, Jürgen M. Reitner, and Ingeborg Wimmer-Frey

Austrian loess and loess loam deposits represent an important source of raw materials for the heavy clay industry for centuries. Building material quality of loess and loess loam deposits and their suitability for different applications is significantly influenced by their heterogeneous properties. These depend on the geology of the source area, climatic conditions, geomorphological location, stratigraphic position, intensity of weathering and redeposition potential. The description of occurrences, properties and availability of these raw materials is therefore an important prerequisite to meet the industrial quality requirements. A large number of different sub-datasets exist at the Geological Survey of Austria, which comprise grain-size analysis, bulk rock composition, clay mineralogy, and geochemistry data of loess and loess loam. Within our project, these individual data sets underwent a thorough examination and have been merged into a coherent database to enable the joint regional and statistical analysis of the data. By applying a log-ratio approach the compositional nature of the analysis data has been taken into account for multivariate statistical methods. 
Within our study we focused on the classic Austrian loess regions in the Northern Alpine foreland areas of Upper and Lower Austria and in the Vienna Basin. By transferring the results of the statistical analysis to a Geographic Information System (GIS) these served as the fundamental basis for our categorization of the loess and loess loam occurrences. Taking into account previously published approaches based on soil profile classifications as well as trends and patterns derived from the analysis data, we finally were able to delineate different districts of brick raw materials deposits. These will be made publically accessible to the industry and interested parties as part of the web application of the Austrian Interactive Raw Material Information System IRIS-Online.

How to cite: Reitner, H., Benold, C., Filzmoser, P., Heinrich, M., Hobiger, G., Mert, C., Rabeder, J., Reitner, J. M., and Wimmer-Frey, I.: Compositional data analysis of sedimentological, mineralogical and geochemical data for the evaluation of Austrian loess and loess loam deposits, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20444, https://doi.org/10.5194/egusphere-egu2020-20444, 2020.

With the development of remote sensing technology, the copyright protection of remote sensing images has become an urgent problem to be solved. In this paper, a blind watermarking scheme based on invariant features is applied. In the embedding process, the stable image features are firstly extracted from the original host using block DCT, and the embedding positions are constructed adaptively according to feature processing theory. Then, the watermark is embedded into the low-frequency coefficients by modifying the DC coefficients. For watermark extraction, according to the invariant image features in each region, the watermark location and the watermark information can be extracted without the original host. Experimental results show that the proposed watermarking is not only invisible and robust against common image processing, such as noise addition, image filtering, and JPEG compression, but also robust against cropping attack.

How to cite: Ren, N. and Zhu, C.: Watermark-based Copyright Protection Using Invariant Features for Remote Sensing Images, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21392, https://doi.org/10.5194/egusphere-egu2020-21392, 2020.

Evaluating digital soil mapping approaches to predict topsoil exchangeable calcium and magnesium in a sugarcane field of Australia

Maryem Arshad1, Dongxue Zhao1, Tibet Khongnawang1 and John Triantafilis1*

1School of Biological, Earth and Environmental Sciences, Faculty of Science, UNSW Sydney, Kensington, NSW, 2052, Australia

Corresponding

John Triantafilis, School of Biological, Earth and Environmental Sciences, Faculty of Science, UNSW Sydney, Kensington, NSW, 2052, Australia

Email: j.triantafilis@unsw.edu.au

Abstract

Knowledge about spatial distribution of exchangeable (exch.) calcium (Ca) and magnesium (Mg) is needed to maintain sugarcane biomass in north Queensland, Australia. To create digital soil maps (DSM), herein, we evaluated three approaches, including; geostatistical (i.e. ordinary kriging [OK]), statistical and hybrid. We first determined the number of samples (10 – 120) required to compute variogram by calculating nugget to sill ratio (NSR) and sum of squared error (SSE). We then used this variogram with OK to predict topsoil (0 – 0.3 m) exch. Ca and Mg. For comparison, four statistical models, including; one linear regression (LR) and three machine learning (ML) models (i.e. Cubist, support vector machine [SVM] and random forest [RF]) were used. Doing so, usefulness of two digital data, including; gamma-ray (g-ray) and soil apparent electrical conductivity (ECa), either individual or combined, was tested. Regression residuals (RR) were then added to find out improvement in prediction performance (i.e. Lin’s) and in hybrid approach. Influence of varying sample size (10 – 120) was also determined on all three DSM approaches. Comparisons were then drawn with a traditional soil type map and by calculating the mean square prediction error (MSPE). Finally, Digital soil maps (DSM) of exch. Ca and Mg were developed. Results showed that 50 samples were enough to compute a good variogram for exch. Ca (NSR = 11%, SSE = 0.39) and Mg (NSR = 33%, SSE = 0.005). Considering OK, exch. Ca and Mg were predicted with moderate agreement (Lin’s = 0.65 – 0.80). Comparing statistical models and to predict exch. Ca, RF (0.64) and SVM (0.63) outperformed Cubist and LR (0.60) while to predict exch. Mg, SVM (0.79), RF and Cubist (0.74) outperformed LR (0.62). Combined and individual g-ray data performed best and equally well. Hybrid models i.e. RK and CubistRR improved prediction of exch. Ca (0.76) and Mg (0.81) using individual g-ray and ECa data, respectively. Considering sample size, OK and statistical models required 80 samples while hybrid models required only 30 samples to satisfactorily (Lin’s ≥ 0.70) predict exch. Ca and Mg. Comparisons based on MSPE showed that to predict exch. Ca, hybrid (RK = 1.44) was the best approach followed by geostatistical (OK = 1.94), statistical (Cubist = 2.15) and then traditional soil map (2.64). Same was the case for exch. Mg. DSM of predicted exch. Ca and Mg were consistent with contour plots of measured data. However, some poor predictions were apparent across field edges or areas where small scale variation in digital or soil data was prevalent.  

How to cite: Arshad, M.: Evaluating digital soil mapping approaches to predict topsoil exchangeable calcium and magnesium in a sugarcane field of Australia, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-292, https://doi.org/10.5194/egusphere-egu2020-292, 2020.

GI2.3 – Learning from spatial data: unveiling the geo-environment through quantitative approaches

EGU2020-7117 | Displays | GI2.3

Geostructural complexity and passive seismic surveys: a geostatistical analysis in the Kathmandu basin

Sebastiano Trevisani, Dev Kumar Maharian, Denis Sandron, Surya Narayan Shrestha, Sarmila Paudyal, Franco Pettenati, and Massimo Giorgi

In this study a set of 39 single station passive seismic surveys conducted in the Kathmandu basin (Nepal), based on the horizontal to vertical spectral ratio methodology (HVSR), is analyzed by means of a geostatistical approach. The Kathmandu basin is characterized by a heterogeneous sedimentary cover and by a complex geostructural setting, inducing high spatial variability of the bedrock depth. In relation to the complex geological setting, the interpretation and analysis of HVSR data are challenging, both from the perspective of bedrock depth analysis as well as of seismic site effects detection. In order to maximize the broad range of information available, the HVSR data are analyzed according to a geostatistical approach. First, the spatial continuity structure of HVSR data is analyzed and interpreted taking into consideration the geological setting and available stratigraphic and seismic information. In addition, we test the possibility to integrate the analysis with potential auxiliary variables, derived from geomorphometric variables and considering the distance from outcropping bedrock. The explorative geostatistical analysis confirms the complexity of the geo-structural setting of the area. Finally, a mapping of HVSR resonance periods, with the evaluation of interpolation uncertainty, is obtained by means of ordinary kriging interpolation. The resulting map, even if characterized by a large interpolation support, is congruent with the geo-structural setting and the main lineaments of the area. The adopted approach is particularly useful in the context of micro-zonation studies based on HVSR methodology conducted in historical urban areas. Moreover, this work contributes to the geo-structural knowledge of the deep structure of the Kathmandu basin.

References

Paudyal YR, Yatabe R, Bhandary NP, Dahal RK, 2013. Basement topography of the Kathmandu Basin using microtremor observation. J Asian Earth Sci 62:627–637, doi.org/10.1016/j.jseaes.2012.11.011.

Nakamura Y., 1989. A method for dynamic characteristic estimation of subsurface using microtremors on the ground surface. Quart. Rep. Railway Tech. Res. Inst. 30, 25-33

Sandron D., S. .Maskey , M. Giorgi, D. V. Maharjan, S. N. Narayan, C. Cravos, F. Pettenati, 2019. Environmental and on buildings noise measures: Laliptur (Kathmandu). Earthquake Engineering. Vol. 60, n. 1, 17-38: March 2019, doi 10.4430/bgta0259.

Trevisani S., Boaga J., Agostini L., Galgaro A., 2017. Insights into bedrock surface morphology using low-cost passive seismic surveys and integrated geostatistical analysis. Science of the Total Environment, 578, 186-202, http://dx.doi.org/ 10.1016/j.scitotenv.2016.11.041.

How to cite: Trevisani, S., Maharian, D. K., Sandron, D., Shrestha, S. N., Paudyal, S., Pettenati, F., and Giorgi, M.: Geostructural complexity and passive seismic surveys: a geostatistical analysis in the Kathmandu basin, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7117, https://doi.org/10.5194/egusphere-egu2020-7117, 2020.

The Dorog Basin is a morphologically unique region of the Transdanubian Mountains revealing the combined work of tectonic forces and erosion. Overprinted by the forms of fluvial erosion, numerous NW-SE striking half-graben and horst structures are present. The surface is dominantly covered by lose 1–15 m thick Quaternary sediments (aeolian loess, and siliciclastic alluvial and coluvial formations), while the lithified bedrock consists of Mesozoic carbonates, Paleogene limestones, marls and sandstones and limnic coal sequences. The rheological difference of the Quaternary and pre-Quaternary formations is so pronounced that the morphological characteristics of the outcrops also differ significantly. The area was in the focus of geologists for many decades, due to its Eocene coal beds, and a renewal of the geological map of the region is in progress. The current research aims to assist the mapping with multivariate methods based on geomorphological attributes, such as slope angle, aspect, profile curvature, height, and topographic wetness index. We perform a random forest classification (RFC) using these variables, to predict the outcrops of pre-Quaternary formations in the study area.

Random forest is a powerful tool for multivariate classification that uses several decision trees, each one with a prediction, where the most popular one will be the overall result [1]. The reason why it is getting popular in spatial predictions is the high accuracy to classify raster-type objects [2]. We used raster-type spatial data as subject of RFC predicting a result for each pixel. The geology of the study area was known from previous geological mapping [3]. Morphological information was derived from the MERIT DEM.

Our model used a raster with multiple bands containing geomorphological variables, and training data from the digitalized geological map. The number of random samples of data was 2500. After testing several combinations of the bands, and several spacing of the study areas, the best prediction has cca. 80% accuracy. Model validation is based on the calculation of rates of well predicted pixels in the same rasterized geological map that was used for training. Our aim was to use exact data, which is completely true for remotely sensed images, but not for geological maps. That means the accuracy still can be improved by field perception, or from borehole data.

 

References:

[1] Liaw, A., & Wiener, M. (2002). Classification and regression by randomForest. R news, 2(3), 18-22.

[2] Belgiu, M., & Drăguţ, L. (2016). Random forest in remote sensing: A review of applications and future directions. ISPRS Journal of Photogrammetry and Remote Sensing, 114, 24-31.

[3] Gidai, L., Nagy, G., & Siposs, Z. (1981). Geological map of the Dorog Basin 1: 25 000. [in Hungarian] Geological Institute of Hungary, Budapest.

How to cite: Pogacsas, R. and Albert, G.: Predicting the outcrop of pre-Quaternary formations in the Dorog Basin (Hungary) using random forest classification, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7255, https://doi.org/10.5194/egusphere-egu2020-7255, 2020.

EGU2020-18101 | Displays | GI2.3

Assessment of slope deposits depth at regional scale by means of morphometric clustering and multi-linear regression: a comparison

Leonardo Disperati, Enrico D'Addario, Michele Pio Papasidero, Marco Pignatiello, Lorenzo Marzini, Michele Amaddii, and Nazariy Broda

Apart high elevation and arid regions, bedrock is generally covered by unconsolidated materials that result from recent or actual bedrock weathering and fracturing, consequent transport along the hillslope mainly by un-channelized flux or gravity-dominated processes and deposition. These slope deposits (SD) are largely affected by shallow landslides triggered during intense rainfall events, hence mapping SD spatial distribution and properties is a challenging task to perform accurate regionalized analysis of landslide hazard.

Nevertheless, geological and geomorphological maps typically represent the spatial distribution of SD following a 0/1 approach, instead of attempting to describe, in a more realistic perspective, the spatial variation of SD depth, even though this latter is a fundamental input parameter for landslide hazard estimation by physically based models.

In this work we present two different approaches to assess SD depth at regional scale, coupling field SD depth measurements, statistical analysis and then topographic-based regionalization: unsupervised clustering and multilinear regression analysis. Geo-environmental variables such as geology, land use and morphometric parameters, have been considered. The unsupervised clustering analysis has been based on some morphometric variables (eg. flow accumulation, slope and hillslope curvatures), derived from a digital elevation model with cell size of 10 m. These variables allowed us to extract, for homogeneous regions obtained by considering bedrock lithology, a set of morphometric units where the distribution of SD depth was assessed. The same variables were processed in the multilinear regression analysis in order to obtain equations estimating the spatial distribution of SD depth. The results of this work were then compared each other, as well as to the outputs obtained by implementing other methods of SD depth estimation known in the literature. Finally, the proposed methods were applied to evaluate SD depth in a test area, where field survey measurements were used as a check to assess the prediction capability. The results are analyzed and discussed in order to identify best solutions to evaluate and represent SD depth at regional scale.

How to cite: Disperati, L., D'Addario, E., Papasidero, M. P., Pignatiello, M., Marzini, L., Amaddii, M., and Broda, N.: Assessment of slope deposits depth at regional scale by means of morphometric clustering and multi-linear regression: a comparison, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18101, https://doi.org/10.5194/egusphere-egu2020-18101, 2020.

EGU2020-9063 | Displays | GI2.3

Spatial assessment of inland excess water hazard using combined machine learning and geostatistical methods

Annamária Laborczi, Csaba Bozán, Gábor Szatmári, János Körösparti, and László Pásztor

Inland excess water (IEW), considered to be a typical Carpathian Basin land degradation problem, is an interrelated natural and human induced phenomenon, which causes several problems in the flat-land regions of Hungary covering nearly half of the country. The term ‘inland excess water’ refers to the occurrence of inundations outside the flood levee that originate from sources differing from flood overflow, it is surplus surface water forming due to the lack of runoff, insufficient absorption capability of soil or the upwelling of groundwater. There is a multiplicity of definitions, which indicate the complexity of processes that govern this phenomenon. Most of the definitions have a common part, namely, that inland excess water is temporary water inundation that occurs in flat-lands due to both precipitation and groundwater emerging on the surface as substantial sources.
Identification of areas with high risk requires spatial modelling, that is mapping of the specific natural hazard. Various external environmental factors determine the behaviour of the occurrence, frequency of IEW. Spatial auxiliary information representing IEW forming environmental factors were taken into account to support the spatial inference of the locally experienced IEW frequency values. Two hybrid spatial prediction approaches, which combine machine learning and geostatistics, were tested to construct reliable maps, namely regression kriging (RK) and Random Forest with Ordinary Kriging (RFK) using spatially exhaustive auxiliary data on soil, geology, topography, land use and climate. Both methods divides the spatial inference into two parts. 
In Regression Kriging the target variable is modelled at first by multiple linear regression (MLR) of the environmental co-variables. Then ordinary kriging is applied on the difference between the reference and the modelled values (residuals). The prediction result map comes from the sum of the MLR model and the interpolated residuals. Random Forest combined with Kriging is a relatively new method applied in digital environmental mapping. In RFK, the deterministic component of spatial variation is modelled by random forest (RF).  RF algorithm builds lots of regression trees and the final model relies on averaging the result of the trees, which are grown independently from each other. In RFK the stochastic part of variation is modelled by kriging using the derived residuals. The final map is the sum of the two component predictions.
Comparing the results of the two approaches, we did not find significant differences in their accuracy in our pilot. However, both methods are appropriate for predicting inland excess water hazard, RFK is suitable for revealing non-linear and more complex relations than RK. Therefore, we suggest the usage of RFK in further predictions and investigations.

Acknowledgement: Our work was supported by the Hungarian National Scientific Research Foundation (OTKA, Grant No. K105167).

How to cite: Laborczi, A., Bozán, C., Szatmári, G., Körösparti, J., and Pásztor, L.: Spatial assessment of inland excess water hazard using combined machine learning and geostatistical methods, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9063, https://doi.org/10.5194/egusphere-egu2020-9063, 2020.

EGU2020-18208 * | Displays | GI2.3 | Highlight

Mapping of Arctic Wetlands with Threats of Future Permafrost Thaw

Elisie Jonsson, Navid Ghajarnia, Gustaf Hugelius, and Zahra Kalantari

The Arctic is warming twice as fast as the rest of the globe, causing changes to Arctic ecosystems. While wetlands in the Arctic provide many ecosystem services with both local and global importance, still more knowledge is needed on the location and state of Arctic wetlands to successfully focus adaptation and mitigation efforts. To understand the links between temperature changes and changes to Arctic wetlands, this study includes the use of spatial tools to map existing wetlands and model permafrost response to temperature changes, highlighting wetland areas with risks of future changes. Using available high-resolution wetland databases together with soil wetness and soil type data, a wetland map covering the Arctic was created. Based on existing relationships between climate and observed permafrost, future changes in permafrost were modeled using projected mean annual temperature from the HadGEM2-ES climate model outputs for the RCP2.6, 4.5 and 8.5 scenarios and for years 2050, 2075 and 2100. We found that the Arctic contains a large number of wetlands and a very significant number of these exist on permafrost. As substantial permafrost thaw is projected, the extent and properties of wetlands will shift, and local/regional increases or decreases in wetland extent will depend on variables such as soil type. These changes could lead to serious local consequences, such as threats to food and water security, changes in distribution and demographics of animal and plant species, and losses and disruptions of infrastructure. The findings of this study highlight vulnerable areas that need extra attention in terms of adaptation and mitigation efforts to limit the likely impacts of projected changes, given the current trends.

Keywords: Arctic wetland, spatial modeling, permafrost, climate change

How to cite: Jonsson, E., Ghajarnia, N., Hugelius, G., and Kalantari, Z.: Mapping of Arctic Wetlands with Threats of Future Permafrost Thaw, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18208, https://doi.org/10.5194/egusphere-egu2020-18208, 2020.

EGU2020-474 | Displays | GI2.3

Detecting hotspots of changes in spatial pattern of forest fragmentation in the Romanian Carpathian Mountains
not presented

Vasilică-Dănuț Horodnic, Vasile Efros, Dumitru Mihăilă, Luminița-Mirela Lăzărescu, and Petruț-Ionel Bistricean

Landscape fragmentation is the expression of patchiness and spatial heterogeneity of land cover pattern. After the breakdown of the socialism regime in 1989, Romania has undergone significant changes at the level of political, institutional and socio-economic profile, which determined researchers to consider this country an experimental territory for land use and landscape research.

The aim of present study is to detect hotspots of changes of forests landscape fragmentation patterns in the Romanian Carpathian Mountains over the last 28 years. In order to meet our demand we applied a holistic approach to assess the multiple teleconnections between forest cover changes and the degree of fragmentation at regional scale for two distinct periods that make up the 1990-2018 period: (1) 1990-2006 (land restitution period or transition period to the market economy) and (2) 2006-2018 (post-accession period to the European Union).

The analysis were carried out using freely available time series CORINE Land Cover data of 1990, 2006 and 2018 provided by Copernicus Land Monitoring Services. The initial spatial datasets were processed with the help of Geographic Information Systems (GIS), while GUIDOS, a free software toolbox dedicated to quantitative analysis of digital landscape images, was used to generate spatial and statistics data of the degree of forest landscape fragmentation.

Our findings indicate that the first period of analysis was more dynamic regarding forest cover changes with a gross area gain of 316 304 ha (7.59%) and a gross area loss of 147 496 ha (3.54%) leading to a net forest area change of 168 808 ha (4.05%) which reflects the level of forest recovery. The change pattern of fragmentation classes showed that 332 045 ha (71.47%) of fragmentation decrease is found for the transition of dominant forest in 1990 into the less fragmented class interior in 2006, while 67 418 ha (65.10%) of all fragmentation increase is found for transition from interior in 1990 to dominant in 2006. The other side, for the period from 2006 to 2018 we found a gross area gain of 127 146 ha (2.93%) and a gross area loss of 212 933 ha (4.91%) leading to a net forest area change of -85 787 ha (-1.98%) which emphasizes the level of forest disturbance. In the same time frame, the high values of fragmentation pattern have been registered for the same classes, 56.82% for fragmentation decrease and 70.60% for fragmentation increase, respectively. The results highlight the reversible impact of land use change on land cover pattern, spatially shaped through afforestation in the first period of analysis and through deforestation in the second period. The afforestation process were determined by high rate of external migration, while deforestation process is a consequence of land restitution laws (Law no. 247/2005), which caused considerable mutations in the ownership of land.

The study emphasizes the impacts of land use policies and land management practices on the pattern of forest landscape and the usefulness of Guidos Toolbox, a universal digital image object analysis, to detect hotspots of changes at regional scale.

How to cite: Horodnic, V.-D., Efros, V., Mihăilă, D., Lăzărescu, L.-M., and Bistricean, P.-I.: Detecting hotspots of changes in spatial pattern of forest fragmentation in the Romanian Carpathian Mountains, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-474, https://doi.org/10.5194/egusphere-egu2020-474, 2020.

EGU2020-18984 | Displays | GI2.3

Predicting the impact of Giant Molerat influenced vegetation on Sanetti Plateau, Bale Mountains, Ethiopia

Luise Wraase, Victoria Reuber, Philipp Kurth, Nina Farwig, Georg Miehe, Lars Opgenoorth, Dana Schabo, and Thomas Nauss

Ecosystem engineers continuously shape and re-shape the spatial and temporal structure of the environment. Burrowing animals are an important group of ecosystem engineers, because of their ability to rework sediments and soils with consequences for e.g. soil formation and vegetation patterns. Simultaneous, burrowing animals depend on climate, local soil characteristics and vegetation. The endemic Giant Molerat (GMR) is a burrowing animal and important ecosystem engineer in the Bale Mountains. As part of the Bale Mountain Exile Hypothesis Project, the aim of this study is to investigate (1) the interlinkages between GMR, climate and vegetation patterns as well as (2) to upscale the influence of GMR on the vegetation pattern across the plateau with Sentinel satellite data. Field data comprise 47 paired plots of 5m x 5m with and without GMR activity. Additionally, 1.500 independent GMR burrow openings have been mapped. For investigating interlinkages, all parameters are first pre-analysed for correlations and their dependencies (1). In the following these results, the remote sensing data and the individual variables are implemented into the prediction model. To increase the accuracy, an error correction of the model is pursued. For this, the area is calculated into likelihoods of areas influenced by GMR, based on the vegetation survey pairs serving as training areas for the correction. The corrected results are used as final input model in a machine learning-based classification approach using Random Forest with forward-feature selection and leave-feature-out option (2). In the following the results of this ongoing upscaling approach used for the Sanetti Plateau, Ethiopia is presented.

How to cite: Wraase, L., Reuber, V., Kurth, P., Farwig, N., Miehe, G., Opgenoorth, L., Schabo, D., and Nauss, T.: Predicting the impact of Giant Molerat influenced vegetation on Sanetti Plateau, Bale Mountains, Ethiopia, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18984, https://doi.org/10.5194/egusphere-egu2020-18984, 2020.

Shallow restrictive soil layer may enhance plant growth and development in dry years due to the creation of subsurface-minipond-like water storages in dry years and may hamper plant development in wet years due to overwetting. These effects may manifest itself differently under different nutrient management. The objective of this work was to see there exist spatial patterns that are temporally stable (do not change over several years), can explain substantial proportions of spatiotemporal variation of maize yield, and can be related to subsurface restrictive layer topography and fertilizer application. Empirical orthogonal functions (EOFs) were good candidates to express such patterns. Data were collected with yield monitors across maize fields with manure applications, uniform chemical fertilization, and precision farming-based chemical fertilizer application over the six-year period. The subsurface restrictive layer was found at depths from one to three meters using the ground penetration radar. Three EOFs explained around 60, 30 and 10 % of interannual yield variation, respectively. As evidenced by semivariograms, the spatial structure was well pronounced in EOFs at the manured field and to a lesser extent at the chemical fertilizer fields. Little difference was observed in cumulative probability distributions of the first EOF across fields with different fertilizer applications. The topography of the restrictive layer was analyzed to determine the subsurface preferential flow lateral flow pathways that could provide water accumulation in dry years and enhanced drainage in wet years. The first EOF on average increased as the distance to the subsurface flow pathways decreased both at the manure and uniform chemical fertilized field, but not at the precision fertilization field where unfavorable water availability conditions could be compensated by the improved fertilizer availability. Differences in the soil surface topography could be reflected by the second EOF. Overall, the temporal stability in crop yields reveals the topography of the shallow vadose zone boundary as the powerful control of yield variation in space and time.  

How to cite: Kim, S., Daughtry, C., Russ, A., and Pachepsky, Y.: Using empirical orthogonal functions to interpret the spatiotemporal variability of crop yields in presence of shallow restrictive soil layer, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11684, https://doi.org/10.5194/egusphere-egu2020-11684, 2020.

EGU2020-8226 | Displays | GI2.3

Possibilities and challenges of modelling the agricultural tracks at field scale

Katja Augustin, Michael Kuhwald, and Rainer Duttmann

The application “FiTraM” (Field Traffic Model) models the spatially explicit wheel tracks and the field traffic intensity of agricultural vehicles from recorded GPS points. The spatial location of traffic intensities are required to analyse the effect of field traffic on the soil structure, e.g. with regard to mitigate soil compaction. The modelling is based on geometrical and geodetical calculations. The application is written in python and uses PostgreSQL and PostGIS for data storing and calculation of statistics.
The results of FiTraM are the spatially mapped wheel tracks, wheel pass frequency, wheel load and the soil pressure induced by machines (optionally). With continuous route recording various operations (sowing, harvesting, soil tillage) can be analysed in terms of the intensity of travel and the complete process chain during single crops can be mapped. These results (e.g. amount of wheel passages, summed wheel load) can be related to further soil measurements to link field traffic intensities with loss of soil functionality or reduced yield.
This contribution intends to illustrate the process of modelling the field traffic intensity by means of different agricultural working processes - from data acquisition to the statistical evaluation of the spatial modelling results. Examples of different traffic operations are used to explain how driving behaviour needs to be taken into account for modelling, such as reversing and lifting equipment (e.g. during soil tillage). The difficulties, such as the evaluation of the positional accuracy in the field and the processing of the large data sets, will be addressed.

How to cite: Augustin, K., Kuhwald, M., and Duttmann, R.: Possibilities and challenges of modelling the agricultural tracks at field scale, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8226, https://doi.org/10.5194/egusphere-egu2020-8226, 2020.

EGU2020-13262 | Displays | GI2.3 | Highlight

Multifractality in Humanitarian Applications

Małgorzata Jenerowicz, Anna Wawrzaszek, Wojciech Drzewiecki, Michał Krupiński, and Sebastian Aleksandrowicz

     Every year the total number of people who had been forcibly displaced (refugees, asylum seekers, and internally displaced persons) is constantly rising, a fact that is directly reflected in the area covered by IDP/refugee camps. Long-term humanitarian relief requires reliable and comprehensive information that is constantly delivered during a crisis. Very High Resolution (VHR) optical satellite data have been shown to be useful in monitoring IDP/refugee camps as it can provide an overview of the affected areas with a spatial resolution of up to 0.3 m within a matter of days.

     The aim of our research is to verify the usefulness of multifractal parameters as descriptors of IDP/refugee camps area, both in the context of their applicability and usability in the humanitarian related issues. In particular, we perform studies devoted to: (I) the complex terrain situation description with the division into compact and dispersed structures; and (II) the identification of IDP/refugee camps area extent aiming at distinguishing residential areas from other land use/land cover types. The analysis performed in two IDP/refugee camps, i.e. Ifo and Ifo 2 (Daadab) in Kenya and Al Geneina in Sudan, based on GeoEye-1 and Pléiades-1A VHR satellite data, gives a promising aspect of limited calculation time needed for the initial stage of image classification in respect to the spatial complexity of analysed terrain. Our results show that the degree of multifractality calculated for the selected images increases for compact areas with high-contrast structures (e.g., functional buildings and dwellings). Consequently, the extraction of the IDP/refugee camps extent by using only one feature, i.e., the degree of multifractality, proved to be an efficient way for initial image classification.

     We hope that our studies supplemented by further research, i.e. pre- and post-processing, the inclusion of multispectral bands, analyzing other areas of interest, and examining the added value of other multifractal measures, will help to develop an unsupervised classification approach providing results more quickly, with more frequent updates.

 

Research supported by the National Science Centre, Poland, under Grant 2016/23/B/ST10/01151.

How to cite: Jenerowicz, M., Wawrzaszek, A., Drzewiecki, W., Krupiński, M., and Aleksandrowicz, S.: Multifractality in Humanitarian Applications, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13262, https://doi.org/10.5194/egusphere-egu2020-13262, 2020.

EGU2020-6478 | Displays | GI2.3

Building spatial-temporal NO2 land use regression models in complex urban environment

Peng Wei, Yang Xing, Li Sun, and Zhi Ning

Air quality and traffic-related pollutants in urban areas are major concerns especially in meg-cities. Current Air Quality Monitoring Station (AQMS) cannot sufficiently reveal these pollution conditions with limited point measurements and limited information cannot supply adequate insight on personal exposure in a complex urban environment. Land Use Regression (LUR) model provided a feasible solution for estimating outdoor personal exposure by adding multiple data sources. However, fixed-site passive monitoring still lacks enough spatial coverage or spatial flexibility to estimate pollutant distribution at the fine-scale level.

A Mobile Air Sensor Network (MASEN) project was deployed in the Hong Kong area, with electrochemical gas sensors installed on the routine buses to capture on-road NOx pollutant measurement, the data was collected by the integrated sensor system and transfer to the database for real-time visualization. Compared with previous mobile measurements used for LUR model building which limited to 1-2 routes, this measurement covered major roads in the Hong Kong area and get an overview of pollutant distribution at various ambient. Two main variables were introduced to improve the model performance: 1) Sky View Factor (SVF) which represented pollutant dispersion status were obtained from Google street view image, a deep learning model was used for scene parsing to recognized targets in this procedure, 2) a Real-time Traffic Congestion Index (RTCI) which represented traffic pollutants emission was obtained from Google map and merged with road network. A common LUR model will be built based on a distance-decay regression selection strategy for variables selection. Meanwhile, a spatial-temporal LUR model will be built which contained both diurnal variability and day-to-day variability. Finally, a high-resolution pollution map of the urban areas will illustrate NO2 pollutant distribution.

In this work, we aimed at estimating traffic-related pollutants in a complex city environment and identifying hotspots at both spatial and temporal aspects. Meanwhile, the novel data source which closely associated with traffic-related pollutant emission also gives a better understanding of guidance on urban planning.

How to cite: Wei, P., Xing, Y., Sun, L., and Ning, Z.: Building spatial-temporal NO2 land use regression models in complex urban environment, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6478, https://doi.org/10.5194/egusphere-egu2020-6478, 2020.

EGU2020-7350 | Displays | GI2.3

Spatial Multicriteria Decision Analysis (SMCDA) for the construction of the European Geogenic Radon Migration map

Giancarlo Ciotoli, Monia Procesi, MariaGrazia Finoia, Peter Bossew, Giorgia Cinelli, Tore Tollefsen, Javier Elìo, and Valeria Gruber

Radon generation, migration and exhalation into the atmosphere are natural processes that can lead to infiltration of radon into indoor environments, thus constituting a health risk. Analyses and models of these three processes can be used to create different maps depicting the potential of geological radon sources (GRS), geogenic radon migration (GRM), and radon exhalation (REX). The latter includes the first two processes, and be used to identify areas with increased radon levels in buildings (Radon Prone or Priority Areas, RPA). Here, we limit our analysis to the first two processes, and propose a spatial technique to map the contribution of some geological factors to the potential radon risk or geogenic radon potential (GRP) at European scale. The GRP can be understood as a measure of susceptibility of a location or of an area to increased indoor radon concentration for geogenic reasons.

The problem of estimating GRP has been examined over several years, using different multivariate statistical and spatial techniques. A number of direct and indirect models have been developed in order to create GRP maps (i.e., susceptibility maps) of a certain region by using both deterministic and probabilistic models. Direct models can be ascribed to multivariate regression of some predictors, but this was possible only at local scale where the response variables (i.e. soil gas radon and thoron) are available. The indirect mapping method integrates many factors and criteria and weighs the importance of the factors, based on subjective decision-making rules according to the experience of the geoscientists involved, or on multivariate statistical analysis.

In this work, we first propose to construct/create a GRP map at European level by using a GIS-based (spatial) multicriteria decision analysis (SMCDA) to quantify the geogenic contribution to indoor radon; and then, to create a European map of geogenic radon priority areas. SMCDA involves combining and handling of different criteria that determine the presence of a RPA, then uses the Analytical Hierarchy Process (AHP) to assess their importance and derives the relative weights for factors and criteria; finally it determines the overall final scores. The GRS map was derived by using a new lithological classification of the International Geological Map of Europe. Lithologies were ranked according to the mean content of uranium, thorium and potassium associated with each lithology. The GRS map was then coupled with maps of other parameters that serve as proxies for permeability, such as available water capacity and the fine fraction of the soil, the fault density and the map of the karst areas. All these maps were standardised by using the max score function and weighted by using AHP. A variance-based sensitivity analysis was conducted to define the uncertainty of the final map. In the absence of direct soil gas measurements, the final map was validated by using the indoor radon values collected by the JRC in the framework of the European Atlas of Natural Radiation. The work is conducted as a task within the framework of the European Metro RADON project (http://metroradon.eu/).

How to cite: Ciotoli, G., Procesi, M., Finoia, M., Bossew, P., Cinelli, G., Tollefsen, T., Elìo, J., and Gruber, V.: Spatial Multicriteria Decision Analysis (SMCDA) for the construction of the European Geogenic Radon Migration map, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7350, https://doi.org/10.5194/egusphere-egu2020-7350, 2020.

In Germany a vast amount of spatial geo-environmental as well as climatic datasets is available. But anthropic data on land-use and agriculture are still very sparse making it difficult to assess the environmental impacts of different agricultural practices. Recently, some data on spatial pattern of crop production as well as livestock production was made publicly available. It opened up the opportunity to model the impact of agriculture on nitrate leaching into groundwater bodies.

A high share of groundwater bodies in Germany contains nitrate levels above the legal threshold of 50 mg l-1. Our study aims to answer the question: to what extend different types of agriculture are contributing to NO3 leaching into ground water bodies in relation to environmental factors.

We use the random forest (RF) machine learning algorithm to model and predict nitrate exceedance in ground water bodies. The advantage of the RF algorithm is that it has a high predictive accuracy, it is able to use metric as well as multi-level categorical datasets and it calculates a variable importance measure for each predictor used in a model. It therefore gives a measure to which extend each predictor contributes to the accuracy of the model. For this study we applied the RF classification as well as the RF regression algorithms on different spatial scales.

Out of 56 environmental predictor datasets which are of potential importance for NO3 transport into groundwater bodies 22 where chosen to model NO3-exceedance.
A recursive variable elimination scheme was applied to calculate minimum predictor sets based on variable importance. In the end the predictor set which resulted in the most accurate NO3 prediction was identified and used to model groundwater pollution.

RF-modeling proofed to be successful on all three scale levels with OBB accuracy between 0.82 and 0.95. At all scale levels environmental co-variables played a major role in predicting NO3-exceedance. But the RF variable importance measure could also be used to identify the contribution of agricultural predictors to NO3 exceedance and to quantitatively proof our hypotheses.

On main challenge was to identify the influence of data quality on the RF variable importance measure.

How to cite: Schneider, C.: Making use of open geo-environmental and agricultural datasets to model NO3 pollution in groundwater bodies, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22527, https://doi.org/10.5194/egusphere-egu2020-22527, 2020.

EGU2020-19388 | Displays | GI2.3

Innovative graphical-numerical methods to investigate compositional changes in groundwater systems

Roberta Sauro Graziano, Renguang Zuo, Antonella Buccianti, Orlando Vaselli, Barbara Nisi, Marco Doveri, and Brunella Raco

Groundwater systems are typical dissipative structures and their evolution can be affected by non-linear dynamics. In this framework, geochemical and hydrological processes are often characterized by random components mixed with intermittency and presence of positive feedbacks between fluid transport and mineral dissolution. Therefore, in these cases, complex variability structures in the chemical signature of waters are recognized. Large fluctuations in intermittent processes are not rare as in normal and log-normal processes and significantly contribute to the statistical moments, thus moving the physicochemical data from the Euclidean geometry to fractals and multifractals.

Since the knowledge of dynamics in water systems has substantial implications in the management of the water resource, groundwater chemistry can better be understood by using innovative graphical and numerical methods in the light of the Compositional Data Analysis Theory (CoDA, Aitchison, 1986), which is particularly suitable to explore the whole composition and the relationships between its parts.

The whole compositional change, characterizing each sample with respect to some end-members (i.e. rain waters, pristine waters and sea water), is modeled by using the perturbation operator in the simplex geometry (Pawlowsky-Glahn and Buccianti, 2011). Perturbation factors are calculated and then analyzed by investigating their cumulative distribution function (Pr[X>=x]) with the aim of registering the presence of power laws (fractal and multifractal dynamics) and forecasting a possible spatial behavior.

Results obtained for some aquifers from Tuscany (central Italy) are presented and discussed in the framework of the GEOBASI project (Nisi et al., 2016). Preliminary evaluations indicate that perturbation factors are sensible tools to: 1) identify the different components (random, deterministic, fractal) contributing to the variability of the geochemical data, 2) discriminate the role of additive and multiplicative phenomena in time and/or space, 3) highlight the presence of non-linear dissipation with the energy exchanges between different scales.[Office1] 

 

Aitchison, J., 1986.  The statistical analysis of compositional data. Monographs on Statistics and Applied Probability (Reprinted in 2003 by The Blackburn Press), Chapman and Hall, 416 p.

Nisi, B., Buccianti, A., Raco, B., Battaglini, R., 2016. Analysis of complex regional databases and their support in the identification of background/baseline compositional facies in groundwater investigation: developments and application examples. Journal of Geochemical Exploration 164, 3-17

Pawlowsky-Glahn, V., Buccianti, A., 2011. Compositional Data Analysis: Theory and applications. Chichester, John Wiley & Sons, 378 p.

How to cite: Sauro Graziano, R., Zuo, R., Buccianti, A., Vaselli, O., Nisi, B., Doveri, M., and Raco, B.: Innovative graphical-numerical methods to investigate compositional changes in groundwater systems, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19388, https://doi.org/10.5194/egusphere-egu2020-19388, 2020.

EGU2020-21502 | Displays | GI2.3

Water-sediment interaction in the Arno- and Tiber river catchments (central Italy)

Petra Diendorfer, Caterina Gozzi, Anna Bauer, Antonella Buccianti, Gerd Rantitsch, Robert Scholger, Barbara Nisi, and Orlando Vaselli

The Tiber and the Arno river basins, represent the first (17,156 km2) and the second (8,228 km2) largest catchments in the peninsular Italy, respectively. The recent combined sampling (2017-2019)  of river waters and sediments in the heterogeneous geological environment of the Apennines enables the assessment of the geochemical and mineralogical interaction between bedrock, river sediments and water. The mineralogical and geochemical composition of the stream sediments are related to the corresponding lithological composition of the hydrological catchment, thus assessing physical weathering within the river basins. On the other hand, chemical weathering is assessed by the analysis of hydrochemical data from the Arno and Tiber rivers and their main tributaries. Locally, anthropogenic processes overprint the natural signature and the magnetic properties of the sediments provide effective data to map those areas. The application of multivariate robust statistical techniques on the combined dataset evaluates the water-sediment interaction and their spatial properties in central Italy. The main goal of this research is to investigate how the linkage between surface waters and steam sediments chemistry can be influenced by catchment-specific properties (e.g. landscape attributes, anthropic impact and climate) through an effective comparative analysis between two of the most important Italian watersheds.

How to cite: Diendorfer, P., Gozzi, C., Bauer, A., Buccianti, A., Rantitsch, G., Scholger, R., Nisi, B., and Vaselli, O.: Water-sediment interaction in the Arno- and Tiber river catchments (central Italy), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21502, https://doi.org/10.5194/egusphere-egu2020-21502, 2020.

GI2.4 – Usefulness of remote sensing, numerical models, and machine learning for assessing climate extreme risks

EGU2020-553 | Displays | GI2.4

Wave downscaling using machine learning

Sara Santamaria Aguilar and Thomas Wahl

Future changes in the wind wave climate due to atmospheric changes can intensify present erosion and flood risk. Knowledge on both mean and extreme wave climate is necessary for understanding changes in sediment dynamics and flood events at the coastline. In order to assess potential wave changes, ensemble nearshore wave projections are required for covering   the entire range of wave conditions and also the large uncertainties related to future climate states. However, nearshore wave projections are not available for most coastal regions due to the excessive computational effort required for dynamically downscaling ensemble offshore wave data. As a result, the large relative contribution of waves to coastal flooding and erosion is commonly omitted in the assessment of those hazards. In this context, machine learning models can be an efficient tool for downscaling ensemble global wave projections if they are able to accurately simulate the non-linear processes of wave propagation due to their low computational requirements. Here, we analyse the performance of three machine learning methods, namely random forest, multivariate adaptive regression splines and artificial neural networks, for downscaling the wave climate along the coast of Florida. We further compare the performance of these three models to the multiple linear regression, which is a statistical model frequently used, although it does not account for the non-linearities associated with wave propagation processes. We find that the three machine learning models perform better than the multiple linear regression for all wave parameters (significant wave height, peak and mean periods, direction) along the entire coastline of Florida, which highlights the ability of these models to reproduce the non-linear wave propagation processes. Specifically, random forest shows the best performance and the lowest computational training times. In addition, this model shows a remarkably good performance in simulating the wave extreme events compared to the other models. By following a tree bagging approach, random forest can also provide confidence intervals and reduce the tuning process. The latter is one of the main disadvantages of the artificial neural networks, which also show a high performance for wave downscaling but require more training and tuning effort. Although the significant wave height and the periods can be simulated with very high accuracy (R2 higher than 0.9 and 0.8 respectively), the wave direction is poorly simulated by all models due to its circular behaviour. We find that a transformation of the direction into sine and cosine can improve the model performance. Finally, we downscale an ensemble of global wave projections along the coast of Florida and assess potential changes in the wave climate of this region.   

How to cite: Santamaria Aguilar, S. and Wahl, T.: Wave downscaling using machine learning, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-553, https://doi.org/10.5194/egusphere-egu2020-553, 2020.

EGU2020-12162 | Displays | GI2.4 | Highlight

Watershed water-energy balance dynamics and their association with diverse influencing factors at multiple time scales

Shengzhi Huang, Jing Zhao, and Kang Ren

The Budyko curve is an effective tool for estimating how precipitation (P) partition into evapotranspiration (E) and streamflow (Q). Controlling the shape of the Budyko curve, the Budyko parameter represents the superimposed impact of various periodic factors (including climatic factors, catchment characteristics, teleconnection factors and anthropogenic activities) on the watershed water-energy balance dynamics, and such superimposed impact is not conducive to identifying the driving factors of the dynamic change of Budyko parameter at different time scales, and thus affect the parameter estimation. Here we obtain the dynamic change of Budyko parameter for the Wei River Basin (WRB)-a typical Loess Plateau region in China based on a 11-years moving window, and then adopt the Empirical Mode Decomposition (EMD) method to reveal the relationships between influencing factors and Budyko parameter series at multiple time scales by considering the interplay among different influencing factors. Results indicate that (1) Budyko parameter series are decomposed into 4-, 12-, 20-, exceeding 20-year time scale oscillations and a residual component with an significantly increasing trend in the upstream of the WRB (UWR) and the middle and lower reaches of the WRB (MDWR), a non-significantly decreasing trend in the Jing River Basin (JRB) and Beiluo River Basin (BLRB); (2) by analyzing the residual trend component, evaporation ratio (E/P), soil moisture (SM) and effective irrigated area (EIA) are found to induce the significant increase of parameter in the UWR, whereas that in the MDWR is dominated by baseflow (BF) and Niño 3.4; (3) parameter dynamics at the 4-year time scale is dominated by E/P, aridity index (EP/P), BF and SM; BF, PDO and sunspots attribute to the dynamics at 12-year time scale; all the factors except BF and SM contribute to the dynamics at 20- or exceeding 20-year time scales. The results of this study will help identify the connection between watershed water-energy balance dynamics and changing environment at multiple time scales, and also be beneficial for guiding water resources management and ecological development planning on the Loess Plateau region.

How to cite: Huang, S., Zhao, J., and Ren, K.: Watershed water-energy balance dynamics and their association with diverse influencing factors at multiple time scales, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12162, https://doi.org/10.5194/egusphere-egu2020-12162, 2020.

EGU2020-13957 | Displays | GI2.4

Crop Yield Estimation Using Multi-source Satellite Image Series and Deep Learning

Gohar Ghazaryan, Sergii Skakun, Simon König, Ehsan Eyshi Rezaei, Stefan Siebert, and Olena Dubovyk

Timely monitoring of agricultural production and early yield predictions are essential for food security. Crop growth conditions and yield are related to climate variability and extreme events. Remotely sensed time-series can be used to study the variability in crop growth and agricultural production. However, the choice of remotely sensed data and methods is still an issue, as different datasets have different spatiotemporal characteristics. Thus, our primary goal was to study the impact of applying different remotely sensed time series on yield estimation in U.S. at the county and field scale. Furthermore, the impact of crop growth conditions on yield variability was assessed. For county-level analysis, MODIS-based surface reflectance, Land Surface Temperature, and Evapotranspiration time series were used as input datasets. Whereas field-level analysis was carried out using NASA’s Harmonized Landsat Sentinel-2 (HLS) product. 3D convolutional neural network (CNN) and CNN followed by long-short term memory (LSTM) were used. For county-level analysis, the CNN-LSTM model had the highest accuracy, with a mean percentage error of 10.3% for maize and 9.6% for soybean. This model presented robust results for the year 2012, which is considered a drought year. In the case of field-level analysis, all models achieved accurate results with R2 exceeding 0.8 when data from mid growing season were used. The results highlight the potential of yield estimation at different management scales.

How to cite: Ghazaryan, G., Skakun, S., König, S., Eyshi Rezaei, E., Siebert, S., and Dubovyk, O.: Crop Yield Estimation Using Multi-source Satellite Image Series and Deep Learning, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13957, https://doi.org/10.5194/egusphere-egu2020-13957, 2020.

EGU2020-15701 | Displays | GI2.4 | Highlight

Analysis of Rice Yield in CHINA by Climate Change using Deep Neural Network

Su-Bin Cho and Yang-Won Lee

Climate change is an important factor in crop growth, and it is significant to understand the relationship between climate change and rice yield. This study used annual rice yield from the USDA(United States Department of Agriculture) for each of China’s 16 administrative regions from 1979 to 2009, as well as average climate data from July to August, which were meteorological observations collected from the CRU(Climate Research Unit). The relationship between selected rice yield and climate change was nonlinear and modelled using a deep neural network to train even rows and verify odd rows of data. This study is expected to contribute to better food self-sufficiency and forecast future grain yields in China.

How to cite: Cho, S.-B. and Lee, Y.-W.: Analysis of Rice Yield in CHINA by Climate Change using Deep Neural Network, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-15701, https://doi.org/10.5194/egusphere-egu2020-15701, 2020.

EGU2020-16520 | Displays | GI2.4

Satellite time series analysis of vegetation dynamics for water resources management in semi-arid regions

Robert Behling, Sigrid Roessner, and Saskia Foerster

One of the consequences of global climate change is the more frequent occurrence of extreme weather conditions. Semi-arid regions are especially vulnerable since evapotranspiration significantly exceeds precipitation for most of the year and rainfall occurrence is dominantly sporadic and highly variable in amount and spatial extent. Consequently, these regions suffer from droughts of increasing duration and severity, occasionally interrupted by strong rainfall events generating high surface runoff and in part highly destructive floods. In semi-arid regions water retention capability is often further reduced by changes of the original vegetation cover due to conversion into farmland and intensification of land use. The result is widespread land degradation by a decrease in permanent vegetation cover and an increase in soil erosion. Under such conditions sustainable water resources management is of key importance, however, reliable long-term observations describing the water cycle and the resulting water budget are missing for many regions of the world. This situation requires new approaches in improving seasonal forecast for relevant water resources parameters as well as spatiotemporally explicit understanding the of influence of water and land use management on the long-term development of water availability and land surface conditions. 
The German collaborative research project ‘Seasonal water resources management in semi-arid regions: Transfer of regionalized global information to practice’ (SaWaM) aims at the development of methods allowing the use of global data for deriving information needed for regional water resources management in semi-arid regions by integrating meteorological, hydrological and ecosystem sciences and supported by satellite remote sensing analysis. The performance, practical applicability and transferability of the developed methods are assessed in several semi-arid regions including Brazil, Iran and Sudan. Here, we present our work on the analysis of the seasonal and long-term vegetation dynamics at different spatial and temporal scales using satellite time series data of different spatial and temporal resolution (MODIS and Sentinel-2).  Our goal is linking the derived vegetation dynamics to changes in meteorological conditions, water availability and land use. In this context we put emphasis on the spatiotemporal analysis of bioproductivity related to different land use types and climatic conditions to identify and characterize hotspots of water usage in form of irrigated agriculture as a basis for further evaluation of the underlying water management practices.
We perform time series analysis of satellite-derived vegetation indices (VI) using various statistical aggregates, such as maximum, mean and temporal duration related to variable time periods (hydrological year, dry and wet season, growing patterns) as well as additive time series decomposition. Thus, we analyze long-term trends, seasonal deviations from long-term average conditions, and break points in the time series related to land use and water management changes. Moreover, we compare the derived spatiotemporal VI dynamics against the dynamics of hydrometeorological conditions (e.g. precipitation, evapotranspiration, temperature) as well as land use patterns in order to evaluate the impact of hydrometeorological drought conditions on different land use types and water management practices.  In conclusion, we present prototypes for information products supporting decision making of the local experts in the target regions.

How to cite: Behling, R., Roessner, S., and Foerster, S.: Satellite time series analysis of vegetation dynamics for water resources management in semi-arid regions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16520, https://doi.org/10.5194/egusphere-egu2020-16520, 2020.

EGU2020-17825 | Displays | GI2.4

Artificial Intelligence for Improvement of Convective System Tracking and Its Surface Effect Prediction

Tran Vu La, Christophe Messager, Rémi Sahl, and Marc Honnorat

Thanks to the geostationary meteorological satellites of METEOSAT (Europe), GOES (USA), and Himawari (Japan), the nowcast of convective systems (CS) can be performed in most of the world with a 5-15-minute observation time sampling and about 2.8-km spatial resolution (up to about 1-km for the new-generation satellites).

However, the CS forecast, including the prediction of their effects on the surface, is still a challenge due to the lack of high-resolution radar data and a deep understanding of this topic. Indeed, for now, most numerical weather prediction (NWP) models cannot deliver an accurate time and space estimation of surface wind patterns and wind gusts associated with the CS.

In the meantime, Synthetic Aperture Radar (SAR) and ASCAT (scatterometers) may be used for the detection of surface wind patterns potentially associated with the deep convective clouds that may be identified on METEOSAT images. Additionally, the intensity of wind patterns may be estimated from SAR and ASCAT data. Based on this result, Deep Learning (or Machine Learning) is proposed in an ongoing study for improving the predictions of wind gusts, based on the combination of several data sources such as SAR, ASCAT, METEOSAT. The obtained results of this step will be used to integrate into the current NWP models.

How to cite: La, T. V., Messager, C., Sahl, R., and Honnorat, M.: Artificial Intelligence for Improvement of Convective System Tracking and Its Surface Effect Prediction, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17825, https://doi.org/10.5194/egusphere-egu2020-17825, 2020.

EGU2020-18580 | Displays | GI2.4

Identification of droughts from monitored and modelled vegetation condition for improved water management in semi-arid areas

Anita Bayer, Christine Mihalyfi-Dean, Robert Behling, Christof Lorenz, Saskia Foerster, Sigrid Roessner, and Almut Arneth

Semi-arid areas suffer from small amounts and a large variability in rainfall combined with an increasing risk of droughts under climate change. These long and short-term changes in water availability directly affecting regional livelihoods are depicted in the condition of the rather sparse vegetation. In this study, seasonal and long-term trends in indicators of the vegetation condition related to water availability and droughts (NDVI vs. fAPAR, NPP, soil water content, excess water) are identified from remote sensing data (MODIS) and a process-based dynamic vegetation model (LPJ-GUESS) for at least two semi-arid river basins. Identified trends of both methods are compared and evaluated based on the underlying processes and related to knowledge of past drought events. Finally, we answer the question, which methods and indicators are suitable to identify changes in the vegetation condition preceding a drought and during drought phases considering the methods and indicators as above plus simple precipitation-based drought indicators (e.g. standardized precipitation index, SPI) and enhanced drought indicators applying multiple indicators theirselves (e.g. combined drought indicator, CDI). The study is imbedded in the SaWaM project (Seasonal Water Management for semi-arid areas) and contributes to improved water management in the project regions by the integrated analysis of remote sensing and ecosystem modelling results that are made available to regional stakeholders tasked with water management in an online tool .

How to cite: Bayer, A., Mihalyfi-Dean, C., Behling, R., Lorenz, C., Foerster, S., Roessner, S., and Arneth, A.: Identification of droughts from monitored and modelled vegetation condition for improved water management in semi-arid areas, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18580, https://doi.org/10.5194/egusphere-egu2020-18580, 2020.

EGU2020-18591 | Displays | GI2.4 | Highlight

A pan-African high-resolution drought index dataset

Jian Peng, Simon Dadson, Feyera Hirpa, Ellen Dyer, Thomas Lees, Diego G. Miralles, Sergio M. Vicente-Serrano, and Chris Funk

Droughts in Africa cause severe impacts such as crop failure, food shortages, famine, epidemics and even mass migration. To minimize the effects of drought on water and food security over Africa, a high-resolution drought dataset is essential to establish robust drought hazard probabilities and to assess drought vulnerability considering a multi- and cross-sectorial perspective that includes crops, hydrological systems, rangeland, and environmental systems. Such assessments are essential for policy makers, their advisors, and other stakeholders to respond to the pressing humanitarian issues caused by these environmental hazards.  In this study, a high spatial resolution Standardized Precipitation-Evapotranspiration Index (SPEI) drought dataset is presented to support these assessments. We compute historical SPEI data based on Climate Hazards group InfraRed Precipitation with Station data (CHIRPS) precipitation estimates and Global Land Evaporation Amsterdam Model (GLEAM) potential evaporation estimates. The high resolution SPEI dataset (SPEI-HR) presented here spans from 1981 to 2016 (36 years) with 5 km spatial resolution over the continent of Africa. To facilitate the diagnosis of droughts of different duration, accumulation periods from 1 to 48 months are provided. The quality of the resulting dataset was compared with coarse-resolution SPEI based on Climatic Research Unit (CRU) Time-Series (TS) datasets, and Normalized Difference Vegetation Index (NDVI) calculated from the Global Inventory Monitoring and Modeling System (GIMMS) project, as well as with root zone soil moisture modelled by GLEAM. Agreement between the coarse resolution SPEI from CRU TS (SPEI-CRU) and the developed SPEI-HR provides confidence in the estimation of temporal and spatial variability of droughts in Africa with SPEI-HR. In addition, agreement of SPEI-HR versus NDVI and root zone soil moisture – with average correlation coefficient (R) of 0.54 and 0.77, respectively – further suggests that SPEI-HR can provide valuable information to study drought-related ecological and societal impacts at sub-basin and district scales in Africa. The dataset is archived in Centre for Environmental Data Analysis (CEDA), with link: http://dx.doi.org/10.5285/bbdfd09a04304158b366777eba0d2aeb (Peng et al., 2019). 

 

Peng, J.; Dadson, S.; Hirpa, F.; Dyer, E.; Lees, T.; Miralles, D.G.; Vicente-Serrano, S.M.V.-S.; Funk, C. (2019): High resolution Standardized Precipitation Evapotranspiration Index (SPEI) dataset for Africa. Centre for Environmental Data Analysis, 05 August 2019. doi:10.5285/bbdfd09a04304158b366777eba0d2aeb.

How to cite: Peng, J., Dadson, S., Hirpa, F., Dyer, E., Lees, T., Miralles, D. G., Vicente-Serrano, S. M., and Funk, C.: A pan-African high-resolution drought index dataset, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18591, https://doi.org/10.5194/egusphere-egu2020-18591, 2020.

EGU2020-19248 | Displays | GI2.4

The role of Evapotranspiration and Water Use Efficiency in Agriculture in Portugal

José Vaz, Célia M. Gouveia, and Isabel F. Trigo

Understanding climate variability and change and its impacts on natural systems is becoming more and more important as changes in earth surface condition near surface air temperature and precipitation. Over Portugal, the observed warming trends have been found to be asymmetric with respect to seasonal and diurnal cycles, with greatest warming occurring for the minimum temperature and during winter and spring. These observed trends exert strong influences on agriculture systems, affecting production viability through changes in winter hardening, frost occurrence, growing season lengths and heat accumulation for ripening potential.

Remote sensing technology has been developing steadily and its products can provide many applications in agriculture, namely crop identification, crop growth monitoring and yield prediction. Recently the LSA SAF team set up a strategy to generate long term data records from Meteosat Second Generation satellite series (2004 to present), releasing Land Surface Temperature (LST), Reference Evapotranspiration (ETREF) and Vegetation parameters (FAPAR, LAI and FVC) using a stable set of input data and algorithm, which would be suitable for climate variability and change detection studies. On the other hand, a new product to characterize the ecosystem processes, the Gross Primary Production (GPP), is under production since 2018.

In this work we propose to computed Water Use Efficiency (WUE), as the ratio between Gross Primary Production (GPP) and Reference Evapotranspiration (ETREF), using LSA-SAF Products. WUE translates the exchanges of carbon and water gross fluxes, between natural ecosystem and the atmosphere, allowing to monitor the adaptability of the ecosystems to climate change. The role played by Evapotranspiration and Water Use Efficiency for different crops in Portugal is evaluated, namely on Wine Production for Douro Region. Results for 2018 and 2019 highlights the vulnerability of the different sectors of Douro Region to dry and wet conditions, namely helping to analyze the impact of droughts on Douro wine production.

Acknowledgements: This study was performed within the framework of the LSA-SAF, co-funded by EUMETSAT This work was partially supported by national funds through FCT (Fundação para a Ciência e a Tecnologia, Portugal) under projects CLMALERT (ERA4CS/0005/2016).

How to cite: Vaz, J., Gouveia, C. M., and Trigo, I. F.: The role of Evapotranspiration and Water Use Efficiency in Agriculture in Portugal , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19248, https://doi.org/10.5194/egusphere-egu2020-19248, 2020.

EGU2020-20612 | Displays | GI2.4 | Highlight

Early Warning System for West Nile Virus outbreaks based on Satellite Earth Observation Data

Elisavet Parselia, Charalambos Kontoes, Ioannis Kioutsioukis, Spiros Mourelatos, Christos Hadjichristodoulou, and Nikolaos I. Stilianakis

The aim of this study is the development of an operational Early Warning System (EWS) that will utilize new and enhanced satellite Earth Observation (EO) sensors with the purpose of forecasting and risk mapping the West Nile Virus (WNV) outbreaks. Satellite EO data were leveraged to estimate environmental variables that influence the transmission cycle of the pathogen that leads to WNV, a mosquito-borne disease (MBD). The system was trained with epidemiological and entomological data from the region of Central Macedonia, the most epidemic-prone region in Greece regarding the WNV. The satellite derived environmental parameters of the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Water Index (NDWI), the Land Surface Temperature (LST), precipitation data as well as proximity to water bodies were coupled with meteorological data and were used as explanatory variables for the models. The management and analysis of the big satellite data was conducted with the Open Data Cube (ODC), providing an open and freely accessible exploitation architecture. Statistical and machine learning algorithms were used for short-term forecast, while dynamical models were utilized for the seasonal forecast.The system explores the analysis of big satellite data and proves its scalability by replicating the same models in different geographic regions; e.g the northeastern Italian region of Veneto. This EWS will be used as a tool for helping local decision-makers to improve health system responses, take preventive measures in order to curtail the spread of WNV in Europe and address the relevant priorities of the Sustainable Development Goals (SDGs) such as good health and well-being (SDG 3) and climate action (SDG 13).

How to cite: Parselia, E., Kontoes, C., Kioutsioukis, I., Mourelatos, S., Hadjichristodoulou, C., and Stilianakis, N. I.: Early Warning System for West Nile Virus outbreaks based on Satellite Earth Observation Data , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20612, https://doi.org/10.5194/egusphere-egu2020-20612, 2020.

Water-driven soil erosion is the most widespread form of soil degradation worldwide, which threatens to the sustainability of agriculture. Climate change may aggravate the threat of erosion. On the basis of the Revised Universal Soil Loss Equation, combined with Geographic Information Systems (GIS), we assessed spatiotemporal variances in global water erosion risk trends during the period 1992–2015 using the linear regression model. The research objective was to explore the spatial pattern of global water erosion risk change in recent decades and to identify the driving factors. The results show that the global water erosion risk increased over 54% of the surface during 1992–2015, with an average rate of 0.17 t·ha-1·yr-2. The lands with significant increasing trends (p < 0.05) accounted for 12% of global lands, with an average rate of 0.27 t·ha-1·yr-2. In which, over 75% regions with significant increasing trends were croplands and forest lands in the cold climate zone as the rainfall intensity increased. However, the increasing rates of soil erosion risk on bare lands and croplands were extremely larger than that on lands with natural vegetation, which means that water erosion on natural lands had much lower sensitive to rainfall changes. These results suggest that improving vegetation conditions in the region with sensitive climate change could reduce the erosion threat.

How to cite: Xiong, M.: Global water soil erosion risk associated with climate change, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20942, https://doi.org/10.5194/egusphere-egu2020-20942, 2020.

Understanding historical crop yield response to climate change is critical for projecting future climate change impacts on yields. Previous assessments rely on statistical or process-based crop models, but each has its own strength and weakness. A comprehensive comparison of climate impacts on yield between the two approaches allows for evaluation of the uncertainties in future yield projections. Here we assess the impacts of historical climate change on global maize yield for the period 1980-2010 using both statistical and process-based models, with a focus on comparing the performances between the two approaches. To allow for reasonable comparability, we develop an emulator which shares the same structure with the statistical model to mimic the behaviors of process-based models. Results show that the simulated maize yields in most of the top 10 producing countries are overestimated, when compared against FAO observations. Overall, GEPIC, EPIC-IIASA and EPIC-Boku show better performance than other models in reproducing the observed yield variations at the global scale. Climate variability explains 42.00% of yield variations in observation-based statistical model, while large discrepancy is found in crop models. Regionally, climate variability is associated with 55.0% and 52.20% of yield variations in Argentina and USA, respectively. Further analysis based on process-based model emulator shows that climate change has led to a yield loss by 1.51%-3.80% during the period 1980-1990, consistent with the estimations using the observation-based statistical model. As for the period 1991-2000, however, the observed yield loss induced by climate change is only captured by GEPIC and pDSSAT. In contrast to the observed positive climate impact for the period 2001-2010, CLM-Crop, EPIC-IIASA, GEPIC, pAPSIM, pDSSAT and PEGASUS simulated negative climate effects. The results point to the discrepancy between process-based and statistical crop models in simulating climate change impacts on maize yield, which depends on not only the regions, but also the specific time period. We suggest that more targeted efforts are required for constraining the uncertainties of both statistical and process-based crop models for future yield predictions. 

How to cite: Yin, X. and Leng, G.: Global contribution of climate variability and trends to maize yield change in observations and crop models during 1980-2010, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21042, https://doi.org/10.5194/egusphere-egu2020-21042, 2020.

EGU2020-21240 | Displays | GI2.4

Improvement of satellite-based land surface temperature estimation

Seoyeon kim and Yangwon lee

Land surface temperature is crucial in many field of study, such as Earth's surface water cycle, energy balances, energy exchange of ecosystem and  global climate change. As the role of LST is important, it should be accurately obtained on a global scale. However, it is still difficult to calculate LST from satellite because there are constraints of Atmospheric correction, cloud effect, verification representatively. Therefore, the goal is to improve and optimize the accuracy of LST estimates in satellite-based measurement by mixing various data such as multi-spectral thermal infrared image, hyperspectral thermal infrared image, microwave satellite image, etc., or comparing and applying many LST calculation methods and algorithms.

How to cite: kim, S. and lee, Y.: Improvement of satellite-based land surface temperature estimation, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21240, https://doi.org/10.5194/egusphere-egu2020-21240, 2020.

EGU2020-21243 | Displays | GI2.4

Deep learning-based prediction of fish catch for the offshore waters in south korea

You jeong yoon and Yang won lee

Recently in Korea, the fish catch of offshore waters recorded less than 1 million tons in 44 years due to climate change and drastic changes in the fishing environment. Therefore, it is essential to produce and provide accurate fishing forecast information, such as the location of fishing fields and the amount of fish production, that varies in time and space according to fishing conditions to enhance the competitiveness of the fishing industry. Since the factors affecting the fish catch have various and nonlinear relationships, so this study predicted the catch based on deep learning. The study was selected as the three major fish species of the Korean coast -- anchovy, mackerel and squid. The research area was selected as four fishing area. (One fishing area is 14 km * 14 km). In order to produce accurate forecasted fishing information, it is necessary to identify major marine weather and biological factors affecting the fish catch by fish species and artificial intelligence modeling using marine and weather satellite images. The satellite data used in the study are from the Korea Meteorological Administration (KMA). So far, research on the relationship between two or more factors and fish catches has been insufficient in the previous research, so this study may contribute to the prediction of fishing trends.

How to cite: yoon, Y. J. and lee, Y. W.: Deep learning-based prediction of fish catch for the offshore waters in south korea, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21243, https://doi.org/10.5194/egusphere-egu2020-21243, 2020.

GI2.5 – Data fusion, integration, correlation and advances of non-destructive testing methods and numerical developments for engineering and geosciences applications

EGU2020-13899 | Displays | GI2.5 | Highlight

Health Monitoring of Masonry Arch Bridges by Integration of GPR and InSAR Techniques

Valerio Gagliardi, Luca Bianchini Ciampoli, Fabio Tosti, Andrea Benedetto, and Amir M. Alani

Approximately 70,000 masonry arch bridge spans (brick and stone) are reported to exist in the United Kingdom with in excess of tens of thousands throughout Europe. A good portion of these bridges is still operational and form part of the road and rail network systems in many countries. However, a great majority of these structures require desperate repair and maintenance [1].

Non-destructive testing (NDT) methods such as ground penetrating radar (GPR), 3D laser scanning, accelerometer sensors and thermal cameras amongst many others have been used to assess and monitor such structures in the past few years [2]. However, research has proven that stand-alone or integrated use of ground-based techniques may not represent a definitive solution to some major structural issues, such as scour and differential settlements [3], as these require continuous monitoring and data collection on long-term basis. To that extent, use of satellite data-based synthetic aperture radar (SAR) interferometry (InSAR) has proven to be effective in measuring displacements of infrastructure [4] [5] and natural terrain [6] over longer periods of observation.

Within this context, the paper presents a new integrated monitoring approach including use of the GPR and the InSAR techniques to an historic masonry arch bridge - the Old Aylesford Bridge in Kent, UK – a 13th century bridge, crossing the river Medway. Main objectives of the research were: (1) to prove the viability of low-frequency and high-frequency GPR systems in providing structural detailing of the bridge deck at different depths and resolutions; (2) to be able to measure structural displacements with a millimetre accuracy caused by the seasonal variation of the water level in the river and the river bed soil expansions. Results have proven the viability of the above process to form the basis for an integrated health monitoring mechanism.

 

References

[1] Alani, A.M., Tosti, F., Banks, K., Bianchini Ciampoli, L., Benedetto, A. Non-Destructive Assessment of a Historic Masonry Arch Bridge Using Ground Penetrating Radar and 3D Laser Scanner, IMEKO International Conference on Metrology for Archaeology and Cultural Heritage Lecce, Italy, October 23-25, 2017.

[2] Solla, M., Lorenzo, H., Rial, F.I., Novo, A. (2011). GPR evaluation of the Roman masonry arch bridge of Lugo (Spain), NDT&Int., 44, 8-12.

[3] Selvakumaran, S., Plank, S., Geiß, C., Rossi, C., Middleton, C. (2018). Remote monitoring to predict bridge scour failure using Interferometric Synthetic Aperture Radar (InSAR) stacking techniques, Int. J. .Appl. Earth Obs. and Geoinf. 73, 463-470.

[4] Tosti, F., Gagliardi, V., D'Amico, F. and Alani, A.M., Transport infrastructure monitoring by data fusion of GPR and SAR imagery information. TIS 2019 International Conference of Rome, 23-24 September 2019.

[5] Bianchini Ciampoli, L., Gagliardi, V., Clementini, C. et al. (2019). Transport Infrastructure Monitoring by InSAR and GPR Data Fusion. Surv Geophys. https://doi.org/10.1007/s10712-019-09563-7

How to cite: Gagliardi, V., Bianchini Ciampoli, L., Tosti, F., Benedetto, A., and Alani, A. M.: Health Monitoring of Masonry Arch Bridges by Integration of GPR and InSAR Techniques, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13899, https://doi.org/10.5194/egusphere-egu2020-13899, 2020.

EGU2020-20198 | Displays | GI2.5

The parallel implementation of the full resolution SBAS-DInSAR processing chain for surface deformation analyses in extended urban areas

Michele Manunta, Muhammad Yasir, Sabatino Buonanno, Ivana Zinno, Riccardo Lanari, and Manuela Bonano

The large availability of Synthetic Aperture Radar (SAR) data collected over the last decade by several satellite missions, such as COSMO-SkyMed, TerraSAR-X and Sentinel-1 constellations, has been pushing toward the present Earth Observation (EO) scenario into a “golden age”, which is rapidly moving towards a real Big Data scenario. The widespread use of satellite SAR data have fostered the development of several SAR applications, one of those referred to as Differential SAR Interferometry (DInSAR) technology, which has deeply demonstrated to profitably detect the surface deformations over a wide spatial extent in both natural and anthropic hazard scenarios, through the generation of spatially dense deformation maps with millimetric accuracies. In particular, the advanced DInSAR algorithm referred to as Parallel Small BAseline Subset (P-SBAS) approach allows retrieving the temporal and spatial characteristics of the detected displacements at two spatial resolution scales, referred to as regional (spatial resolution in the 30-90 m range) and local (spatial resolution in the 3-10 m range) scales, suitable for a large variety of application fields, from natural hazards (volcano eruptions, seismic events, landslides) to anthropic contexts (urban areas, archaeological sites, oil-gas extraction, structures and transport infrastructures).

However, the interferometric processing performed at local scale needs to deal with hundreds of SAR acquisitions at full spatial resolution, i.e. to manage several hundreds of million points; consequently, the processing of such a data amount is particularly heavy from a computational point of view and can not be carried out in reasonable time frames through the traditional (sequential) implementation of the full resolution DInSAR processing chains.

Accordingly, to profitably benefit from the current SAR scenario, it is crucial to develop innovative solutions to automatically and efficiently handle large DInSAR data stacks. These solutions are principally based on the exploitation of advanced distributed computing environments, to achieve high efficiency in terms of scalability performances, as well as on the development of much more advanced DInSAR methodologies (and codes) able to effectively maximize the information related to these huge amount of DInSAR data.

This work is aimed at describing an innovative DInSAR solution, based on the exploitation of distributed HPC and Cloud Computing environments, which benefits from parallel programming techniques (multi-node, multi-threads, GPUs) implemented within an automatic full resolution P-SBAS processing pipeline. Starting from large SAR datasets acquired by the COSMO-SkyMed constellation, the developed parallel full resolution P-SBAS processing chain allows retrieving in short time frame (less than 24 hours) displacement time series and deformation maps, at the single buildings/infrastructure level, relevant to extended urban areas. The presented experimental results and the related performance analyses are achieved by applying the developed parallel P-SBAS pipeline to a number of large full resolution COSMO-SkyMed datasets acquired over some important Italian cities (e.g. Rome and Naples urban areas).

How to cite: Manunta, M., Yasir, M., Buonanno, S., Zinno, I., Lanari, R., and Bonano, M.: The parallel implementation of the full resolution SBAS-DInSAR processing chain for surface deformation analyses in extended urban areas , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20198, https://doi.org/10.5194/egusphere-egu2020-20198, 2020.

EGU2020-11982 | Displays | GI2.5

Advanced Bridge Monitoring Strategies by Polarimetric GB-SAR

Lilong Zou, Motoyuki Sato, Fabio Tosti, and Amir M. Alani

Use of advanced health monitoring strategies for bridges is essential to provide a comprehensive condition assessment of these structures and ensure their structural integrity. To this purpose, new technologies have been applied in recent years for both static and dynamic assessments offering unprecedented opportunities within the context of risk management and structural analysis. Among these, areal deformation measurement techniques from ground-based synthetic aperture radar (GB-SAR) sensors were successfully applied for continuous monitoring of dynamic and static displacements of bridges [1] [2]. However, a main limitation for the ground-based microwave interferometry is that, as a linear measurement technique, it is difficult to pinpoint the damage location and obtain accurate displacement time-series for bridges [3]. Moreover, it is known that vertical displacements are usually more relevant than horizontal displacements in the dynamic monitoring of bridges, and the GB-SAR interferometry can only provide the line-of-sight (LOS) displacement of the monitored bridge [4].

In this research, we focus on remote monitoring of the dynamic displacement responses of bridges with a polarimetric GB-SAR system. To this purpose, various strategies were used to overcome the existing limitations of this technique. Results from the monitoring of a long-span metallic railway bridge and a reinforced concrete Shinkansen bridge are discussed.

The aim of this research is to provide more comprehensive and accurate information for bridge health monitoring using a polarimetric sensor. To this extent, a polarimetric analysis was performed to identify the reflection from the side surface of the bridges. In addition, the information about the polarisation orientation angle and the local incidence angle were processed under the acquisition geometry to calculate the radar look angle. Therefore, the bridge deformation fields in the vertical direction were easily converted using the slant range distances and the corresponding maximum transient vertical deformation was transformed through the LOS deformation while a train passing the bridge.

 

References

[1] Monserrat, O. et al., 2014. A review of ground-based SAR Interferometry for deformation measurement. ISPRS Journal of Photogrammetry and Remote Sensing, pp. 40–48.

[2] Pieraccini, M. et al., 2006. Dynamic monitoring of bridges using a high-speed coherent radar. IEEE Transaction Geoscience and Remote Sensing, pp. 3284–3288.

[3] Sato M., Zou L., Nico G., 2017. Monitoring of Infrastructure by GB-SAR. IEICE technical report, pp. 11-16.

[4] Sato M., Zou L., Nico G., Kikuta K., 2019. Displacement and Vibration Monitoring by GB-SAR. IEICE Transactions on Communications, pp.844-852.

How to cite: Zou, L., Sato, M., Tosti, F., and Alani, A. M.: Advanced Bridge Monitoring Strategies by Polarimetric GB-SAR, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11982, https://doi.org/10.5194/egusphere-egu2020-11982, 2020.

EGU2020-8699 | Displays | GI2.5

Persistent Scatterer SAR Interferometry (PSI) for Airport Runways monitoring

Luca Bianchini Ciampoli, Valerio Gagliardi, Fabio Tosti, Alessandro Calvi, and Andrea Benedetto

In the last decades, monitoring the regional-scale deformation of international airports has become a priority, in order to ensure the highest operational security and safety standards. Within this context, among the most innovative and suitable techniques for transport infrastructures monitoring purpose, Persistent Scatterer SAR Interferometry (PSI) technology has proven to be an effective technique to investigate ground deformations [1-3].

However, the application of PSI to effectively and continuously monitor settlement in airports is an open challenge. In this study, a long time-series analysis of a high-resolution COSMO-Skymed satellite image-stack, acquired from September 2011 to October 2019, was collected and processed by PSI technique to retrieve the mean deformation velocity and time series of surface deformation of the runways of Leonardo Da Vinci-International Airport.

The mean PS velocity information is compared to the ground-based levelling-data, collected on the runway using a total station, in order to validate and increase the feasibility of the monitoring processing.

Finally, various Deformation maps using the Natural Neighbor Geostatistical interpolation algorithm [4], were created and demonstrated a maximum subsidence rate is up to 15.3 mm/yr during the investigated period. The results confirmed the well-known major down-lifting phenomenon over an area, which has undergone routine maintenance.

Results have demonstrated the viability of integrating InSAR and topographical in-situ survey methods, paving the way to future implementations in prioritizing maintenance activities and helping for decision-making to have a comprehensive and inclusive information data system for the investigation of survey sites.

The research is supported by the Italian Ministry of Education, University and Research under the National Project “Extended resilience analysis of transport networks (EXTRA TN): Towards a simultaneously space, aerial and ground sensed infrastructure for risks prevention”, PRIN 2017, Prot. 20179BP4SM

 

[1] Bianchini Ciampoli, L., Gagliardi, V., Clementini, C. et al. Transport Infrastructure Monitoring by InSAR and GPR Data Fusion. Surv Geophys (2019). https://doi.org/10.1007/s10712-019-09563-7

[2] Ferretti, A., Prati, C., Rocca, F., 2000. Nonlinear subsidence rate estimation using permanent scatterers in differential SAR interferometry. IEEE Trans. Geosci. 38 (5), 2202–2212. https://doi.org/10.1109/36.868878.

[3] Ferretti, A., Prati, C., Rocca, F.,2001. Permanent scatterers in SAR interferometry. IEEE Trans. Geosci. Remote Sens. 2001, 39, 8–20.

[4] Sibson, R. (1981). "A brief description of natural neighbor interpolation (Chapter 2)". In V. Barnett (ed.). Interpolating Multivariate Data. Chichester: John Wiley. pp. 21–36.

How to cite: Bianchini Ciampoli, L., Gagliardi, V., Tosti, F., Calvi, A., and Benedetto, A.: Persistent Scatterer SAR Interferometry (PSI) for Airport Runways monitoring, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8699, https://doi.org/10.5194/egusphere-egu2020-8699, 2020.

EGU2020-4388 | Displays | GI2.5

Approximating Probabilistic Joint Inversion using Bayesian Spatial Ensemble Fusion

Gerhard Visser, Hoël Seillé, and Jelena Markov

Bayesian posterior sampling is a flexible and general purpose method that can be used to quantify uncertainty in geophysical inversion results. It produces large ensembles of plausible subsurface models consistent with the data and some spatial prior. Unfortunately, it is computationally expensive and becomes impractical for high-dimensional models. This problem is exacerbated by the challenges of joint inversion using data from different geophysical methods, which may be sensitive to different petrophysical properties at different resolutions. To speed up and simplify both implementation and application, we introduce Bayesian spatial ensemble fusion.

The method is demonstrated here using airborne electromagnetic (both VTEM and Tempest) and magnetotelluric data from Cloncurry in the Mount Isa province of Queensland, Australia. 1D transdimensional inversion is applied to individual sites to quantify uncertainty locally, which produces ensembles of 1D layered resistivity models with variable numbers of layers. These local ensembles are then fused together to produce ensembles of more complex 2D models as an approximation to what laterally constrained probabilistic joint ensemble inversion would have produced.

There are several benefits to this approach: Different and existing software can be used by different specialists to create the input ensembles, which reduces the need for complex coordination and simplifies coding. Forward calculations are performed once and then stored to be recycled in many subsequent fusions. Many inversions of the same data, or different combinations thereof, can then be performed using different priors, constraints and geological interpretations, at very little additional cost. Thorough exploratory uncertainty analysis is thus made more practical as specialists can elicit and test different interpretations more quickly.

How to cite: Visser, G., Seillé, H., and Markov, J.: Approximating Probabilistic Joint Inversion using Bayesian Spatial Ensemble Fusion, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4388, https://doi.org/10.5194/egusphere-egu2020-4388, 2020.

EGU2020-19332 | Displays | GI2.5

Understanding distributed data – a semantic web approach for data based analysis of NDT data in civil engineering

Christoph Völker, Benjamin Moreno-Torres, and Sabine Kruschwitz

In the field of non-destructive testing (NDT) in civil engineering, a large number of measurement data are collected. Although they serve as a basis for scientific analyses, there is still no uniform representation of the data. An analysis of various distributed data sets across different test objects is therefore only possible with high manual effort.

We present a system architecture for an integrated data management of distributed data sets based on Semantic Web technologies. The approach is essentially based on a mathematical model - the so-called ontology - which represents the knowledge of our domain NDT. The ontology developed by us is linked to data sources and thus describes the semantic meaning of the data. Furthermore, the ontology acts as a central concept for database access. Non-domain data sources can be easily integrated by linking them to the NDT construction ontology and are directly available for generic use in the sense of digitization. Based on an extensive literature research, we outline the possibilities that this offers for NDT in civil engineering, such as computer-aided sorting, analysis, recognition and explanation of relationships (explainable AI) for several million measurement data.

The expected benefits of this approach of knowledge representation and data access for the NDT community are an expansion of knowledge through data exchange in research (interoperability), the scientific exploitation of large existing data sources with data-based methods (such as image recognition, measurement uncertainty calculations, factor analysis, material characterization) and finally a simplified exchange of NDT data with engineering models and thus with the construction industry.

Ontologies are already the core of numerous intelligent systems such as building information modeling or research databases. This contribution gives an overview of the range of tools we are currently creating to communicate with them.

How to cite: Völker, C., Moreno-Torres, B., and Kruschwitz, S.: Understanding distributed data – a semantic web approach for data based analysis of NDT data in civil engineering , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19332, https://doi.org/10.5194/egusphere-egu2020-19332, 2020.

In order to plan infrastructure maintenance strategies, Non-Destructive Techniques (NDT) have been largely employed in recent years, achieving outstanding results in the identification of infrastructural deficiencies. Nevertheless, the extensive combination of different NDT that can cover various factors affecting infrastructure durability has not yet been thoroughly investigated.

This paper proposes a methodology for evaluating the resilience of infrastructures towards endogenous factors by combining different NDT outcomes. Machine Learning (ML) Regression algorithms have been used to predict the pavement surface roughness connected to a set of potential endogenous conditioning factors. The development, application, and comparison of two different regression algorithms, specifically Regression Tree (RT) and Random Forest (RF) have been carried out.

The study area involves 4 testing sites, both in the rural and urban context, for a total length of 11400 m. In addition to the International Roughness Index (IRI) calculated by profilometric measurements, a set of endogenous features of the infrastructure were collected by using NDT such as Falling Weight Deflectometer (FWD), and Ground Penetrating Radar (GPR). Moreover, a set of topographical data of roadside areas, information on properties of materials composing the subgrade and the pavement structure, traffic flow, rainfall, temperature, and age of infrastructure were gathered.

The database was randomly split into a Training (70%) and Test sets (30%). With the Training set, through a 10-Fold Cross-Validation (CV), the models have been trained and validated. A set of three performance metrics, namely Correlation Coefficient (R2), Root Mean Square Error (RMSE), and Mean Absolute Error (MSE), has been used for the Goodness-of-Fit (GoF) assessment. Also, with the Test set, the Predictive Performance (PP) of the models has been evaluated.

Results indicate that the suggested methodology is satisfactory for supporting processes on planning road maintenance by National Road Authorities (NRA) and allows decision-makers to pursue better solutions.

How to cite: Fiorentini, N., Leandri, P., and Losa, M.: Evaluating Resilience of Infrastructures Towards Endogenous Events by Non-Destructive High-Performance Techniques and Machine Learning Regression Algorithms, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21183, https://doi.org/10.5194/egusphere-egu2020-21183, 2020.

EGU2020-11954 | Displays | GI2.5 | Highlight

Advanced GPR Signal Processing Techniques for Root Detection in Urban Environments

Livia Lantini, Fabio Tosti, Iraklis Giannakis, Kevin Jagadissen Munisami, Dale Mortimer, and Amir M. Alani

Street trees are widely recognised to be an essential asset for the urban environment, as they bring several environmental, social and economic benefits [1]. However, the conflicting coexistence of tree root systems with the built environment, and especially with road infrastructures, is often cause of extensive damage, such as the uplifting and cracking of sidewalks and curbs, which could seriously compromise the safety of pedestrians, cyclists and drivers.

In this context, Ground Penetrating Radar (GPR) has long been proven to be an effective non-destructive testing (NDT) method for the evaluation and monitoring of road pavements. The effectiveness of this tool lies not only in its ease of use and cost-effectiveness, but also in the proven reliability of the results provided. Besides, recent studies have explored the capability of GPR in detecting and mapping tree roots [2]. Algorithms for the reconstruction of the tree root systems have been developed, and the spatial variations of root mass density have been also investigated [3].

The aim of this study is, therefore, to investigate the GPR potential in mapping the architecture of root systems in street trees. In particular, this research aims to improve upon the existing methods for detection of roots, focusing on the identification of the road pavement layers. In this way, different advanced signal processing techniques can be applied at specific sections, in order to remove reflections from the pavement layers without affecting root detection. This allows, therefore, to reduce false alarms when investigating trees with root systems developing underneath road pavements.

In this regard, data from trees of different species have been acquired and processed, using different antenna systems and survey methodologies, in an effort to investigate the impact of these parameters on the GPR overall performance.

 

Acknowledgements

The authors would like to express their sincere thanks and gratitude to the following trusts, charities, organisations and individuals for their generosity in supporting this project: Lord Faringdon Charitable Trust, The Schroder Foundation, Cazenove Charitable Trust, Ernest Cook Trust, Sir Henry Keswick, Ian Bond, P. F. Charitable Trust, Prospect Investment Management Limited, The Adrian Swire Charitable Trust, The John Swire 1989 Charitable Trust, The Sackler Trust, The Tanlaw Foundation, and The Wyfold Charitable Trust. This paper is dedicated to the memory of our colleague and friend Jonathan West, one of the original supporters of this research project.

 

References

[1] J. Mullaney, T. Lucke, S. J. Trueman, 2015. “A review of benefits and challenges in growing street trees in paved urban environments,” Landscape and Urban Planning, 134, 157-166.

[2] A. M. Alani, L. Lantini, 2019. “Recent advances in tree root mapping and assessment using non-destructive testing methods: a focus on ground penetrating radar,” Surveys in Geophysics, 1-42.

[3] L. Lantini, F. Tosti, Giannakis, I., Egyir, D., A. Benedetto, A. M. Alani, 2019. “A Novel Processing Framework for Tree Root Mapping and Density Estimation using Ground Penetrating Radar,” In 10th International Workshop on Advanced Ground Penetrating Radar, EAGE.

How to cite: Lantini, L., Tosti, F., Giannakis, I., Munisami, K. J., Mortimer, D., and Alani, A. M.: Advanced GPR Signal Processing Techniques for Root Detection in Urban Environments, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11954, https://doi.org/10.5194/egusphere-egu2020-11954, 2020.

EGU2020-12233 | Displays | GI2.5

Constrained Surface-wave Dispersion Inversion Using GPR Reflection Data

Shufan Hu, Yonghui Zhao, Wenda Bi, Ruiqing Shen, Bo Li, and Shuangcheng Ge

Ground penetrating radar (GPR) and Seismic Surface Wave methods (SWMs) are two nondestructive testing (NDT) methods commonly used in near-surface site investigations. These two methods investigate the media properties of subsurface based on different physical phenomena. GPR has a good resolvability to characterize the layered structure since the propagation of electromagnetic wave is sensitive to the change of electrical properties, while, the geometric dispersion of surface waves can be used to retrieve the variation of S-wave velocity (Vs) with depth. In most situations, these two data sets are processed separately, and the results are later used for comprehensive interpretation. Constrained inversion, as a way to implement data fusion, can alleviate the non-uniqueness of the solution and produce more consistent information for the comprehensive site and material investigations.

We present an algorithm for the inversion of surface-wave dispersion curves with GPR interface constraints in 2D media. The reflection interfaces interpreted from the GPR profile are integrated into a cell- and boundary-based Vs model. This implementation allows both vertical and lateral changes within each region while also allows sharp changes across the boundaries. In addition, our algorithm simultaneously inverts several dispersion curves extracted along the survey line using multi-size spatial windows, which mitigates the adverse effects of 1D assumption in traditional surface-wave dispersion inversion and improves the matching of GPR and SWMs in lateral variations. We use synthetic and field data sets to test the effectivity of the proposed method. Both results show the improved resolution of the Vs model retrieved by the constrained inversion compared to the standard inversion.

How to cite: Hu, S., Zhao, Y., Bi, W., Shen, R., Li, B., and Ge, S.: Constrained Surface-wave Dispersion Inversion Using GPR Reflection Data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12233, https://doi.org/10.5194/egusphere-egu2020-12233, 2020.

EGU2020-11677 | Displays | GI2.5

Comparative study of steel corrosion characterization by visible and THz imaging techniques

Jean Dumoulin, Ilaria Catapano, Jean-Marc Moliard, Giovanni Ludeno, Thibaud Toullier, and Francesco Soldovieri

Transport infrastructures play a significant role in the economy of countries. However, in European countries, transport infrastructures aging (>40 years) and traffic increase require to develop in-situ efficient inspection and maintenance solutions. Monitoring of steel and composite structures are important issues for sustainability of existing and new infrastructure. Classical approach relies on large human activities eventually performed in unsafe conditions. To overcome the problem on site contactless global automated measurement methods are to be favoured.

For apparent corrosion, visible imaging coupled with image processing allows to detect and characterize the extension of the defective area. Anyway, characterization of corrosion thickness and nature require complementary measurements. Among imaging techniques, knowing that corrosion acts as a insulating layer, active infrared thermography is a possible approach [1-2]. But here we will focus on the complementary approach based on THz-TDS imaging as investigated and tested for corrosion detection under painting with preliminary corrosion type classification [2].

In the present study, we first performed a measurement campaign on several steel samples at different corrosion stages. Typically, three stages were investigated: from non-corroded with paint coating, to pitting corrosion up to fully corroded sample surface.

Data were gathered by means of the Z-Omega Fiber-Coupled Terahertz Time Domain (FICO) system working in a high-speed reflection mode and were processed by using a properly designed data processing chain recently proposed in [3] and involving a noise filtering procedure based on the Singular Value Decomposition (SVD) of the data matrix. Complementary post-processing approach for quick detection and characterization were added to these filtered data.

The obtained results, which will be presented in detail at the conference, allowed us to state the imaging capabilities offered by the adopted instrumentation and obtain valuable information on the surveyed specimens, such as the corrosion thickness connection with apparent pseudo-intensity images. Finally, perspectives on coupling techniques will be introduced.

Acknowledgments:

Authors wish to thank Research Fund for Coal and Steel for funding part of this work under grant agreement No 800687 in the framework of DESDEMONA project.

 

References

[1] A. Crinière, J. Dumoulin, C. Ibarra-Castanedo and X. Maldague ,” Inverse model for defect characterization of externally glued CFRP on reinforced concrete structures: Comparative study of square pulsed and pulsed thermography “, Quantitative InfraRed Thermography Journal, Taylor & Francis Editor, vol 11, pp 84-114, 2014. DOI: 10.1080/17686733.2014.897512.

[2] T. Sakagami, D. Shiozawa, Y. Tamaki, H. Ito A. Moriguchi, T. Iwama, K. Sekine and T. Shiomi, “Nondestructive detection of corrosion damage under corrosion protection coating using infrared thermography and terahertz imaging, in. Proc AITA 2015 conference, pp. 229-233, 2015.

[3] I. Catapano, F. Soldovieri, “A Data Processing Chain for Terahertz Imaging and Its Use in Artwork Diagnostics".J Infrared Milli Terahz Waves, pp.13, Nov. 2016.

How to cite: Dumoulin, J., Catapano, I., Moliard, J.-M., Ludeno, G., Toullier, T., and Soldovieri, F.: Comparative study of steel corrosion characterization by visible and THz imaging techniques, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11677, https://doi.org/10.5194/egusphere-egu2020-11677, 2020.

EGU2020-20841 | Displays | GI2.5 | Highlight

GPR and Microwave Tomography for the Assessment of Hollowed Tree Trunks

Fabio Tosti, Francesco Soldovieri, Ilaria Catapano, Iraklis Giannakis, Gianluca Gennarelli, Livia Lantini, Giovanni Ludeno, and Amir M. Alani

The danger related to the structural stability of hollowed trees is a matter of wide discussion among the scientific community. Hollow cores in trees can extend to more than 50% of the total diameter [1] and, while the presence of a hollow tree might appear dramatic in terms of public safety, it is not always a cause of concern. It is known that hollow trees can form in many years or even decades [2] and, although the heartwood is effectively dead, the tree can continue to form sapwood on the exterior of the trunk to create a cylinder. However, robustness and structural support provided by this cylinder to the trunk and canopy above depend on the ratio of healthy to diseased tissue.

In this context, Ground Penetrating Radar (GPR) has proven to be an effective non-invasive tool, capable of generating information about the inner structure of tree trunks in terms of existence, location, and geometry of defects [3], [4]. Nevertheless, it had been observed that the currently available and known GPR-related processing and data interpretation methods and tools are able to provide only limited information on the tree inner structure.

In this study, we present a microwave tomographic approach for improved GPR data processing with the aim of detecting and characterising the geometry of hollowed trees. Tests were performed at Gunnesbury Park, London, UK. In particular, a number of 15 circular measurements were collected around the tree using the Aladdin 2 GHz hand-held antenna system manufactured by IDS GeoRadar (Part of Hexagon), covering a height of 140 cm. The tree was eventually felled and three sections were cut for validation purposes.

Results presented in this abstract are part of a major research project that the authors have undertaken for the last three years.

 

Acknowledgements

The authors would like to express their sincere thanks and gratitude to the following trusts, charities, organisations and individuals for their generosity in supporting this project: Lord Faringdon Charitable Trust, The Schroder Foundation, Cazenove Charitable Trust, Ernest Cook Trust, Sir Henry Keswick, Ian Bond, P.F. Charitable Trust, Prospect Investment Management Limited, The Adrian Swire Charitable Trust, The John Swire 1989 Charitable Trust, The Sackler Trust, The Tanlaw Foundation, and The Wyfold Charitable Trust. This paper is dedicated to the memory of our colleague and friend Jonathan West, one of the original supporters of this research project.

 

References

[1] Braithwaite, R.W. (1985). The Kakadu fauna survey: an ecological survey of Kakudu National Park. Canberra, Australia: Australian Parks and Wildlife Service.

[2] Ruxton, G.D. (2014). Why are so many trees hollow? Biology Letters, 10 (11).

[3] Giannakis, I., Tosti, F., Lantini, L., Alani, A.M. (2019). Diagnosing Emerging Infectious Diseases of Trees Using Ground Penetrating Radar, IEEE Transactions on Geoscience and Remote Sensing. doi: 10.1109/TGRS.2019.2944070

[4] Alani, A.M., Soldovieri, F., Catapano, I., Giannakis, I., Gennarelli, G., Lantini, L., Ludeno, G., Tosti, F. (2019). The Use of Ground Penetrating Radar and Microwave Tomography for the Detection of Decay and Cavities in Tree Trunks. Remote Sens., 11, 2073.

How to cite: Tosti, F., Soldovieri, F., Catapano, I., Giannakis, I., Gennarelli, G., Lantini, L., Ludeno, G., and Alani, A. M.: GPR and Microwave Tomography for the Assessment of Hollowed Tree Trunks, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20841, https://doi.org/10.5194/egusphere-egu2020-20841, 2020.

EGU2020-7077 | Displays | GI2.5 | Highlight

Cooperative use of non invasive sensing methodologies for the geophysical monitoring of the archaeological park of Paestum

Luigi Capozzoli, Francesco Soldovieri, Enzo Rizzo, Ilaria Catapano, Giovanni Ludeno, Gianluca Gennarelli, Gregory De Martino, Francesco Uliano Scelza, and Gabriel Zuchtriegel

The deployment of non-invasive sensing methodologies capable of providing information useful to characterize, monitor and manage archaeological sites represents a fundamental step for the conservation/preservation of cultural heritage assets. In the framework of the national project VESTA (funded by the Campania Region), several non invasive activities have been carried out for testing a novel approach of analysis including in situ methodologies, drone and satellite technologies.

This communication deals with a case study carried out at the monumental archaeological site of Paestum, sited in the southern Italy, where Greek settlers founded the ancient city of Poseidonia (6th century B.C.) [1]. At this site, geophysical surveys based on the combined use of magnetometric analyses [2], geoelectrical surveys [3] and ground-penetrating radar measurements [4] have been performed. Specifically, the areas immediately close to the temples of Ceres and Neptune have been investigated to identify unknown and buried archaeological features and characterise the paleo-morphological context. The different resolution and depth of investigations related to the application of each one of the considered methodologies as well as the use of tomographic methodologies for the data processing allowed the collection of images showing different subsurface features of the investigated area at different spatial scale. These images made possible the identification of anomalies of the subsoil, which were useful both to respond to the questions of the archaeologists and give new perspectives for managing the site. At the conference, the results of the integrated geophysical surveys, as well as their archaeological interpretation, will be presented with a focus on the cultural and social value of the “water resource” for the ancient city of Poseidonia.

 

[1] https://www.museopaestum.beniculturali.it/?lang=en

[2] A. Aspinall, C. Gaffney, A. Schmidt, A Magnetometry for archaeologists. Geophysical methods for archaeology, Altamira Press, Lanham (2008).

[3] A. Binley, A. Kemna, DC resistivity and induced polarization methods. InHydrogeophysics Water and Science Technology Library; R. Yuram, S.S- Hubbard, S.S., Eds.; Springer: New York, NY, USA (2005).

[4] D. J. Daniels, Ground penetrating radar, IET (2004).

How to cite: Capozzoli, L., Soldovieri, F., Rizzo, E., Catapano, I., Ludeno, G., Gennarelli, G., De Martino, G., Scelza, F. U., and Zuchtriegel, G.: Cooperative use of non invasive sensing methodologies for the geophysical monitoring of the archaeological park of Paestum, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7077, https://doi.org/10.5194/egusphere-egu2020-7077, 2020.

EGU2020-20265 | Displays | GI2.5

3d stereo reconstruction of train paths for supporting maintenance operations

Massimiliano Nitti, Nicola Mosca, Vito Reno, Patruno Cosimo, Maria diSumma, Roberto Colella, and Ettore Stella

Railway infrastructure maintenance is a critical activity for ensuring safe train operations, due to the constant mechanical stress and wear and tear that crucial parts of the infrastructure such as rail and catenary undergo under use. Several methodologies and systems have been devised for diagnosing and prevent anomalies and minimize safety risks, that measure geometrical parameters and assess the way the infrastructure interacts with the train. While those techniques help at identifying anomalies when they occur, sometimes they are not able to provide enough evidence on the reasons behind the failure. A visual inspection can surely help in assessing the causes of failure, especially when they happen during train operations, without introducing any disruption to the service to schedule a specific check with a visit to the site. This work investigates the design of a stereo vision system that can be mounted on diagnostic trains so that a virtual visit to the site can be done when needed, by providing a 3d reconstruction of the surrounding of a train path. To achieve this, in the proposed system two color cameras can be mounted on the head or tail locomotive in a stereo configuration. They are triggered by an axle encoder mounted on the train at a fixed distance of 2 mt. This way the acquired point clouds can be registered together to achieve a full 3d reconstruction of the train path so that an offline, remote inspection of parts of the rails and catenaries can support in detecting, and possibly prevent, future anomalies. Moreover, since the reconstruction extends beyond train paths for a few meters, the 3d reconstruction of the railway can be exploited in different ways too, for example by preventing that foreign objects invade and jeopardize the train loading gauge.

How to cite: Nitti, M., Mosca, N., Reno, V., Cosimo, P., diSumma, M., Colella, R., and Stella, E.: 3d stereo reconstruction of train paths for supporting maintenance operations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20265, https://doi.org/10.5194/egusphere-egu2020-20265, 2020.

EGU2020-256 | Displays | GI2.5 | Highlight

The blackout of September 2019 on the island of Tenerife: an opportunity to estimate the level of contamination of electromagnetic noise using the magnetotelluric method

David Martínez van Dorth, Luca D'Auria, Juanjo Ledo Fernández, Perla Piña-Varas, Federico Di Paolo, Iván Cabrera-Pérez, Germán Cervigón, Monika Przeor, William Hernández, Pilar Queralt, Alejandro Marcuello, and Nemesio Pérez

The magnetotelluric method (MT) is a geophysical technique that provides high resolution information of the electrical resistivity of the subsurface geological structures by measuring the natural variations of the electromagnetic field recorded on the surface. Among the numerous applications, it can be used to map the presence of fluid reservoirs and localize significant structural contrasts that could be related to the presence of a geothermal or volcanic system. However, the interference of the anthropogenic noise during the MT measurements could affect significantly the correct interpretation of the collected data.

For this reason, in order to evaluate the effect of data contamination by anthropogenic sources, we analyzed the data registered by a continuous recording magnetotelluric station located inside the caldera of Las Cañadas (Tenerife, Spain). The instrumentation consisted of an ADU-08e, equipped with EPF-06 electrodes and MFS-06 magnetic coils. Two electric (Ex, Ey) and three magnetic (Hx, Hy, Hz) components have been recorded. This geophysical station was installed by the Instituto Volcanológico de Canarias (INVOLCAN), with purposes of volcano monitoring, on June 2019 and since then it has been recording data daily in the frequency range of 0.001 – 1000s.

On September 29 (2019) a significant electric blackout took place in the entire island of Tenerife in which, during approximately 6 hours the electricity supply was completely shut down. This situation represented a clear opportunity to obtain raw data almost free of anthropogenic contamination and it could help to quantify the effect of the anthropogenic noise in the MT measurements performed in a densely urbanized area as Tenerife. The first results show the clear change at 13:11:39 local time (GMT) in which both the electrical and magnetic components evidenced a pronounced change in their temporal pattern. Moreover, the comparison of the impedance tensor components between the previous hours and during the blackout reveals a noticeable difference for periods higher than 1 s.

How to cite: Martínez van Dorth, D., D'Auria, L., Ledo Fernández, J., Piña-Varas, P., Di Paolo, F., Cabrera-Pérez, I., Cervigón, G., Przeor, M., Hernández, W., Queralt, P., Marcuello, A., and Pérez, N.: The blackout of September 2019 on the island of Tenerife: an opportunity to estimate the level of contamination of electromagnetic noise using the magnetotelluric method, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-256, https://doi.org/10.5194/egusphere-egu2020-256, 2020.

EGU2020-22059 | Displays | GI2.5

Digital Elevation Models (DEM) for the Analysis of the paved surface of Linear Infrastructures

Margherita Fiani and Alessandro Di Benedetto

The proposed study aims at analyzing effective surveying techniques and methodologies to acquire more detailed metric data and to support traditional surveying techniques on linear infrastructures.

In particular, from measurements acquired with LiDAR technique, it is possible to obtain an accurate 3D model of the infrastructure surface, which can be used to have complete information on its distress conditions.

The particular plano-altimetric development of the road belt makes the classic methods used for DEM extraction unsuitable, on which most modelling software is based, which reconstruct the trend of a given variable according to a regular grid of nodes starting from discrete measured and irregularly distributed values. This is done by means of interpolation techniques with which we arrive at a statistical or deterministic surface, usually in matrix format with a resolution chosen by the user; each element of the matrix corresponds to an elevation value. However, it is evident that a grid structure oriented according to the North-South cartographic grid is not effective to represent the curvilinear development of a road infrastructure.

Therefore, we want to introduce a first methodology to generate a particular curvilinear abscissa DEM, called DEMc, suitable for road pavements, which optimizes not only the computational effort but also the organization and extraction of profiles (longitudinal and transversal) and the plano-altimetric analysis. The construction of this model, represented by a ‘raster’ matrix, is semi-automatic. The elevation value of each single node of the two-dimensional grid is estimated through specially modified spatial and local interpolation processes. The process has been implemented in a Matlab environment.

A more advanced example of the digital paving model was based on the study of the deviation of the paved surface from a reference plane. The process involves the creation of a two-pitched flat surface constructed so as to lay on the real surface (theoretically, a road cross-section is represented by a double pitch to allow water flow). The building of the planes is carried out on road sections as wide as the entire carriageway and between 3 and 5 m long. To ensure that the pitch lays on the surface, an iterative algorithm has been implemented; at each iteration the algorithm excludes the points below the plane obtained by previous interpolation. In this way, in the next cycle, the new plane will be built by interpolation on the basis only of the data that were above the plane at the previous iteration; this method makes the plane orient itself according to the number of points remaining at each iterative cycle. The adjacent pitches, in the direction of travel, are built in such a way as to be mutually joined. This process has been implemented in the Matlab environment as well.

How to cite: Fiani, M. and Di Benedetto, A.: Digital Elevation Models (DEM) for the Analysis of the paved surface of Linear Infrastructures, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22059, https://doi.org/10.5194/egusphere-egu2020-22059, 2020.

EGU2020-7021 | Displays | GI2.5

Predicting the Bearing Capacity of Road Flexible Pavements using GPR

Chiara Ferrante, Luca Bianchini Ciampoli, Fabio Tosti, Amir Morteza Alani, and Andrea Benedetto

Most of the damage in road-flexible pavements occur where stiffness of the asphalt and load-bearing layers is low. To this extent, an effective assessment of the strength and deformation properties of these layers can help to identify the most critical sections [1].

This work proposes an experimental-based model [2] for the assessment of the bearing capacity of road-flexible pavements using ground-penetrating radar (GPR – 2 GHz horn antenna) and the Curviameter [3] non-destructive testing (NDT) methods. It is known that the identification of early decay and loss of bearing capacity is a major challenge for effective maintenance of roads and the implementation of pavement management systems (PMSs). To this effect, a time-efficient methodology based on a quantitative modelling of road bearing capacity is developed in this study. The viability of using a GPR system in combination with the Curviameter NDT equipment is also proven.

The research is supported by the Italian Ministry of Education, University and Research under the National Project “Extended resilience analysis of transport networks (EXTRA TN): Towards a simultaneously space, aerial and ground sensed infrastructure for risks prevention”, PRIN 2017, Prot. 20179BP4SM

 

[1] Frangopol, D.M.; Liu, M. Maintenance and management of civil infrastructure based on condition, safety, optimization, and life-cycle cost. Infrastruct. Eng. 2007, 1, 29–41.

[2] Tosti, C. L. Bianchini, F. D'Amico, A. M. Alani and A. Benedetto, “An experimental-based model for the assessment of the mechanical properties of road pavements using ground-penetrating radar,” Construction and Building Materials, vol. 165, pp. 966-974, 2018.

[3] M. Simonin, J.L. Geffard, P. Hornych, Performance of deflection measurement equipment and data interpretation in France, International Symposium Non-Destructive Testing in Civil Engineering (NDT-CE) September 15–17, 2015, Berlin, Germany.

How to cite: Ferrante, C., Bianchini Ciampoli, L., Tosti, F., Alani, A. M., and Benedetto, A.: Predicting the Bearing Capacity of Road Flexible Pavements using GPR, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7021, https://doi.org/10.5194/egusphere-egu2020-7021, 2020.

EGU2020-3422 | Displays | GI2.5

Data correlation of non-destructive testing methods to assess asphalt pavement thickness

Christina Plati, Andreas Loizos, and Konstantinos Gkyrtis

Performing structural assessment at any time of asphalt pavements service life is an inherent process within pavement condition assessment. Layers thicknesses are among the major contributors to the overall pavement response and performance. Knowledge of layer thicknesses is imperative for both new and in-service pavements, because thickness data is usually combined with other response indicators (i.e. pavement deflections) in order to perform pavement evaluation during pavements service life. As such, inaccuracies in thickness assessment might result in erroneous response analysis and life expectancy estimation with a detrimental financial impact during maintenance planning.

Traditionally, layer thicknesses were retrieved through coring or digging test pits. Because of the limitations of these methods (including location-specific information, destructive nature, need for traffic disruptions), the pavement engineering community has consistently drawn its attention to a broadened utilization of advanced Non-Destructive Testing (NDT) systems in order to non-invasively determine the pavement cross-section. The most indicative NDT tool for that purpose is the Ground Penetrating Radar (GPR), which is systematically used for layers thickness evaluation. Within the framework of pavement evaluation processes, GPR is quite often combined with the Falling Weight Deflectometer (FWD), which provides with pavement response indications in terms of surface deflections.

It is worthwhile mentioning that GPR requires high expertise in order to reliably analyze the collected data and until now, there is none uniquely recognizable and universally accepted signal processing scheme. Supplementary to experienced users and analysts, investments in time and human resources are also needed to make reliable interpretations. Such reasons may potentially discourage related stakeholders from systematic GPR use, especially in cases where there are budgets constraints for the procurement and transportation logistics of multiple expensive equipment.

In light of the above, related research is pursed in respect to the investigation of the ability of FWD surface deflections indexes to provide with reliable information on the Asphalt Concrete (AC) layer thicknesses. For this purpose, Long-Term Pavement Performance (LTPP) data is analyzed including FWD and GPR data as well as sample coring. A nonlinear regression based relationship is under development that preliminarily exhibits a satisfactory performance both during model fit and model accuracy evaluation. Based on the above framework, it is suggested that the NDT analysis with deflection indexes seems promising in terms of roughly producing AC thickness, thereby balancing constraints at network level.

How to cite: Plati, C., Loizos, A., and Gkyrtis, K.: Data correlation of non-destructive testing methods to assess asphalt pavement thickness, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3422, https://doi.org/10.5194/egusphere-egu2020-3422, 2020.

EGU2020-12032 | Displays | GI2.5

Investigating the Causes of Roads Deterioration in the Form of Potholes using Non-Destructive Testing

Muhammad Naveed, Kanishka S. Turrakheil, Fabio Tosti, and Amir M. Alani

Potholes are one of the public’s main local concerns as they cost a lot to the economy in terms of repair bills, delays while repairs are carried out and vehicle wear-and-tear. According to the Annual Local Authority Road Maintenance (ALARM) survey, eliminating the pothole backlog in England and Wales would cost £9.8bn and take a decade to complete despite increased local roads investment. The aim of this study is to research why potholes occur in the first place using non-destructive testing (NDT) and potential remedies in terms of the development of effective design and innovative materials to prevent their formation in future.

To investigate the causes of potholes formation, in-situ use of NDT methods such as ground-penetrating radar (GPR) has proven effectiveness as roads remain in continuous use. Analysis of GPR data can provide information on layer depths, material condition, moisture, voiding, reinforcement and location of other features [1, 2, 3].

Through our results, we will test two hypothesis; (i) shallow potholes are formed on loss of adhesion of the surface course, (ii) deep potholes are formed due to the loss of bearing capacity or settlement of the subgrade. Poor drainage in combination of heavy loads trigger shallow potholes while extreme wetting-drying cycles as a result of climate change decayed subgrade conditions of the pavement.

Results presented in this abstract are part of a PhD project funded by the University of West London.

 

References

[1] Saarenketo, T. and T. Scullion (2000). Road evaluation with ground penetrating radar. Journal of Applied Geophysics (43): 119–138.

[2] Benedetto, A., Tosti, F., Bianchini Ciampoli, L., and F. D’Amico (2016). An overview of ground-penetrating radar signal processing techniques for road inspections. Signal Processing (132): 201-209.

[3] Benedetto, A., Benedetto, F., and F. Tosti (2012). GPR applications for geotechnical stability of transportation infrastructures. Nondestructive Testing and Evaluation, 27 (3): 253–262.

How to cite: Naveed, M., Turrakheil, K. S., Tosti, F., and Alani, A. M.: Investigating the Causes of Roads Deterioration in the Form of Potholes using Non-Destructive Testing, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12032, https://doi.org/10.5194/egusphere-egu2020-12032, 2020.

Concrete is a strongly heterogeneous and densely packed composite material. Due to the high density of scattering constituents and inclusions, ultrasonic wave propagation in this material consists of a complex mixture of multiple scattering, mode conversion and diffusive energy transport. For a better understanding of the effect of aggregates, porosity and of crack distribution on elastic wave propagation in concrete and to optimize inverse techniques it is useful to simulate the wave propagation and scattering process explicitly in the time domain. For this purpose, we use the rotated staggered grid (RSG) finite-difference technique for solving the wave equations for elastic, anisotropic and/or viscoelastic media. This study is part of the CoDA project (DFG project 398216472, FOR 2825), which aims to develop a novel method based on ultrasonic coda wave interferometry (CWI) for the assessment of safety and durability of reinforced concrete structures. For this purpose, the coda technique is a suitable method to detect small changes in concrete members. In order to distinguish changes in the coda signal in terms of their origin (i.e. mechanical load, temperature, moisture), wave propagation simulations are performed to support the experimental investigations within the project. The idea is to create realistic digital twins for the experiments on two different scales: The specimen scale and the structural scale. In this study, high-performance simulations of ultrasonic wave propagation within concrete structures on the specimen scale were performed and evaluated using coda wave interferometry (CWI).

How to cite: Saydak, L. A. and Saenger, E. H.: Concrete Damage Assessment by Coda Waves: Wave propagation simulations to support experimental investigations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20493, https://doi.org/10.5194/egusphere-egu2020-20493, 2020.

EGU2020-20920 | Displays | GI2.5

Incorporation of GPR data into characterization of the bitumen filled cracks in pavements: Lab and numerical study

Mezgeen Rasol, Vega Pérez Gracia, Mercedes Solla, Jorge C. Pais, Francisco M. Fernandes, Caio Santos, and Sam Roberts

Road pavements are subject to a range of problems due to traffic and temperature variations 

producing cracks that propagate to the pavement surface. Cracks need to be assessed to avoid 

deterioration and provide confidence in the functioning of the road system. Cracks are usually 

maintained after visual inspection by filling with bitumen as a first rehabilitation technique to 

avoid further deterioration and absorbing water leakages. Although this temporary solution does 

not extend the pavement life cycle it can help to avoid additional problems occurring within the

pavement. This work is proposed to aid the development of understanding and characterization

of cracks filled with bitumen in both rigid and asphalt pavements.

This study reports on the results of several laboratory experiments that were performed to 

explore the capability of Ground Penetrating Radar (GPR) in the assesment of bitumen-filled 

cracks in both rigid and asphalt pavements, respectively. These tests were focused on the 

analysis of cracking filled with bitumen using a GPR system equipped with a ground-coupled 

antenna with a 2.3 GHz central frequency, and varying the antenna orientation with respect to the 

crack axis.

Results showed the variation in characterization and changes in amplitude that could be expected 

when analysing bitumen-filled cracks in concrete and asphalt specimens, dependent upon the 

antenna orientation being used; GPR B-scans were compared to images from computational 

models using a Finite-Difference Time-Domain (FDTD) method-based software package 

(gprMax2D). Additionally, a field survey carried out provided images consistent with the

comparable conditions of the lab tests. The results of this work proved the capability of the GPR

method to detect and characterize cracks filled with bitumen in pavements across a range of 

crack dimensions and pavement types.

 

Keywords

GPR, NDT, Rigid pavements, Asphalt Pavements, Cracks, Computational models, Target orientation,

Pavement assessmen

How to cite: Rasol, M., Gracia, V. P., Solla, M., Pais, J. C., Fernandes, F. M., Santos, C., and Roberts, S.: Incorporation of GPR data into characterization of the bitumen filled cracks in pavements: Lab and numerical study , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20920, https://doi.org/10.5194/egusphere-egu2020-20920, 2020.

EGU2020-7230 | Displays | GI2.5

EXTRA-TN: A novel approach for an extended resilience analysis of transport networks

Fabrizio D'Amico, Chiara Ferrante, Luca Bianchini Ciampoli, Alessandro Calvi, and Andrea Benedetto

Recent and dramatic events occurred on the Italian transport networks have pointed out the urgent need for assessing the actual state of health along the national transport assets. Analogous considerations can be addressed towards the high exposition and vulnerability of the transport system to major natural events, such as floods or earthquake.

Recently, the administrations and managing companies have increasingly made use of non-destructive techniques for achieving a denser knowledge about the health of the asset.

However, one of the major limitations concerning these methods is that each technology, according to its specific features, is usually suitable for a single specific application and has very limited effectiveness for other tasks. Accordingly, the integration of datasets collected with different NDTs stands as a viable approach to fill technology-specific gaps, thereby ensuring a more comprehensive assessment of the infrastructure [1-3]. Data fusion logic can also potentially allow for further data interpretation from merging different information [4].

The EXTRATN project aims at overcoming the state-of-the-art research in the field of non-destructive monitoring of linear infrastructures and, through a “data fusion” logic, at achieving a comprehensive rate of knowledge about the actual condition of the asset. The addressed concept is a “fully sensed infrastructure”, being sensed by different technologies and with different scopes. Specifically, interferometric synthetic aperture radar (DInSAR), Laser Imaging Detection and Ranging (LiDAR), Ground-penetrating Radar (GPR) and Falling Weight Deflectometer (FWD) are considered to the purpose.

A system of transport infrastructure being located in the Province of Salerno (IT), within an area subjected to hydrogeological risk, has been selected as a study case for the integrated approach. This system includes a motorway, a rural highway and a railway.

As a major advantage with respect to the state-of-the-art, such a methodology allows for analysing the evolution trend of the on-going distresses, meaning a significant upgrade of the monitoring activities that may provide valuable information for a priority-based scheduling of the maintenance.

Moreover, such an approach enables to simultaneously monitor exogenous and endogenous events that may lead to a decrease of the safety, functionality or strength conditions.

The research is supported by the Italian Ministry of Education, University and Research under the National Project “Extended resilience analysis of transport networks (EXTRA TN): Towards a simultaneously space, aerial and ground sensed infrastructure for risks prevention”, PRIN 2017, Prot. 20179BP4SM.

 

  1. Liu W, Chen S, Hauser E (2011) LiDAR-based bridge structure defect detection. Exp Tech 35(6):27–34.
  2. Grasmueck M, Viggiano DA (2007) Integration of ground-penetrating radar and laser position sensors for real-time 3-D data fusion. IEEE Trans Geosci Remote Sens 45(1):130–137.
  3. Solla M et al (2011) Non-destructive methodologies in the assessment of the masonry arch bridge of Traba, Spain. Eng Fail Anal 18(3):828–835
  4. Luo RC, Yih C-C, Su KL (2002) Multisensor fusion and integration: approaches, applications, and future research directions. IEEE Sens J 2(2):107–119.

How to cite: D'Amico, F., Ferrante, C., Bianchini Ciampoli, L., Calvi, A., and Benedetto, A.: EXTRA-TN: A novel approach for an extended resilience analysis of transport networks, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7230, https://doi.org/10.5194/egusphere-egu2020-7230, 2020.

EGU2020-6410 | Displays | GI2.5

Analysis of co-registration performance of KOMPSAT satellite images according to acquisition angles

Jeongho Lee, Yeji Kim, Jongmin Yeom, Seonyoung Park, Youkyung Han, and Taeheon Kim

How to cite: Lee, J., Kim, Y., Yeom, J., Park, S., Han, Y., and Kim, T.: Analysis of co-registration performance of KOMPSAT satellite images according to acquisition angles , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6410, https://doi.org/10.5194/egusphere-egu2020-6410, 2020.

EGU2020-20040 | Displays | GI2.5

A system for detection of tampering on intermodal containers

Nicola Mosca, Simone Negri, Massimiliano Nitti, Roberto Colella, Vito Renò, Antonella Semerano, and Ettore Stella

Shipping containers provide a standard and ubiquitous way to move goods between different places and countries. In fact, a large proportion of the international trade rely on them every day. It is thus understandable the importance of improving transport security of the containers hosting those goods.

It is therefore important to detect the possibility that a container has been tampered, both for avoiding losses due to theft, both for minimizing security risks due to counterfeiting or smuggling of illegal assets as soon as possible.

Standard tampering and intrusion counter-measures include locks, hard walls or reinforced curtains, tamper evident seals, etc. Most of these solutions, however, either need that the shipping company buys suitable containers (e.g. a container with hardened walls), or invest money in adding usually active devices to them (like for IR detection systems, locks, etc.).

A different way to detect anomalies can be achieved if the focus for finding intrusion evidence shifts from containers to the intermodal terminals that will receive the goods once they are offloaded from vessels, aircrafts or trains. A few solutions already exist or are being investigated, but they are usually expensive or difficult to deploy, thus reducing their spread and adoption.

In this work, the focus is on cost-effective, transportable solutions. In this context, various sensing technologies for evaluating the integrity of a container, are being explored, both on their own merits, and in combination with others. In particular, inspection based on colour and texture, 3d shape of the container, response to hyperspectral and thermal imaging are considered. 

Based on the sensors investigation, a cost-effective prototype of a “transportable” multimodal system is being devised. Such system is complemented by colour and 3d snapshot sensors, able to scan and report anomalies on a panel container or part of it. The system is designed to inspect a container and to fit in it while not in use, for logistics consideration. This work will present a prototype being experimented, along with an investigation of the obtainable results and the necessary trade-off that are necessary to develop such a system.

How to cite: Mosca, N., Negri, S., Nitti, M., Colella, R., Renò, V., Semerano, A., and Stella, E.: A system for detection of tampering on intermodal containers, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20040, https://doi.org/10.5194/egusphere-egu2020-20040, 2020.

EGU2020-6307 | Displays | GI2.5

The extent of igneous rocks of the South China Sea based on the correlational analyses of gravity and magnetic data

Min Yang, Wanyin Wang, Xiaolin Ji, Tao Ma, Jie Ma, and Shengqing Xiong

The South China Sea is the biggest conjugate marginal sea in the West Pacific Ocean, which is influenced by the Eurasian plate, the Pacific plate, and the Indo-Australian plate. There have developed continental tectonic margins with different characters after experiencing subduction, collision, strike-slip and so on since the Mesozoic and Cenozoic (Yao et al., 2004; Zhang et al., 2014). However, the igneous rock can be regarded as a recorder to reveal some information of evolution and deep geodynamics of the South China Sea, which helps us to improve understanding of the continental rifting, the seafloor spreading, the formation of deep water basins and the process of hydrocarbon accumulation(Zhang et al., 2016).
The igneous rocks are studied by multiple types of data that are magnetic data, seismic profiles, and drilling data in the previous studies. Hence, there are bunch of research results about the igneous rocks that contain the reason and time of formation, the distribution of space, the period of eruption in the north of the South China Sea because of the abundant datasets (Zou et al., 1993,1995; Zhou et al., Yan and Liu, 2005; Xu et al., 2013; Zhang et al., 2013; Zhang et al., 2014; Zhang et al., 2015; Zhang et al., 2016), in addition, the Pearl River Mouth Basin is the most famous one among all of the basins in the South China Sea. However, the researchs related to the south of the South China Sea where are the deep-sea are far less knowledgeable about the distribution of the igneous rocks than the north because of the limitation of datasets that are poor quality and less quantity (Yao et al., 2004; Li et al., 2010; Hui et al., 2016), which lead to the less researches with respect to the big area of the South China Sea.
The followings can be concluded from the previous studies. The northern and continental margin of the South China Sea are distributed by Cenozoic extrusive rocks with high susceptibility and low density and Yanshanian intrusive rocks with low susceptibility and density (Hao et al., 2009; Lu et al., 2011; Hui et al., 2016), the Central Sub-basin is covered by Cenozoic extrusive rocks (Yan and Liu, 2005; Hui et al., 2016), however, there are few distributions of the Yanshanian intrusive rocks in the Southern South China Sea (Zhang et al., 2015; Hui et al., 2016). In this study, a new method, the fusion of gravity and magnetic data, is applied to detect the distribution of the igneous rocks in order to provide more geophysical data in the South China Sea.

How to cite: Yang, M., Wang, W., Ji, X., Ma, T., Ma, J., and Xiong, S.: The extent of igneous rocks of the South China Sea based on the correlational analyses of gravity and magnetic data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6307, https://doi.org/10.5194/egusphere-egu2020-6307, 2020.

EGU2020-7042 | Displays | GI2.5 | Highlight

The use of GPR in Archaeology: the structural detailing of buried roman baths

Roberta Santarelli, Luca Bianchini Ciampoli, and Andrea Benedetto

Ground Penetrating Radar has widely proven to be an effective tool for archaeological purposes [1-4]. Our contribution concerns a geophysical experimental activity carried out in the Maxentius Complex, an archaeological site located between the second and the third miles of the ancient Appian Way in Rome, Italy. This site is characterized by different phases dated between the end of the 3rd and the beginning of the 4th century AD. The objective of this study is to evaluate the feasibility of GPR, in this case using two different antennas (200 MHz and 600 MHz frequencies), for the structural detailing of buried roman baths structures. As a result, GPR analysis confirmed the literature-based information, i.e. to precisely locate the tanks of the thermal area (2nd century AD). The structure was partially brought to light and reburied during the second half of the last century, providing a partial plan view of the area. In addition, the tomographic results, together with the analysis of B-Scans, highlighted the presence of two further tanks, thereby suggesting the possibility of further rooms which are located close to the known ones. Furthermore, the tomographic analysis revealed a wall pattern that seems to suggest the presence of other rooms in the top-right side of the area. In general terms, GPR demonstrated a great applicability to archaeological purposes, for example to detect buried remains and to interpret the function of buried structures, despite the reliability and productivity of the data interpretation are strongly influenced by the expertise of both the geophysicists and the archaeologists involved.

 

This work falls within the project “ArchaeoTrack”, supported by Regione Lazio, under the Framework “L.R. 13/08, Research Group Project n. 20 prot. 85-2017-14857”.

 

  1. Bianchini Ciampoli, L., Benedetto, A., Tosti, F., {2018} “The ArchaeoTrack Project: Use of Ground-Penetrating Radar for Preventive Conservation of Buried Archaeology Towards the Development of a Virtual Museum”, In. Proc. of MetroArchaeo, Cassino, Italy
  2. Milligan, R., & M., Atkin, {1993}. The use of ground-probing radar within a digital environment on archaeological sites, in Andresen, J., Madsen, T. and Scollar, I., eds., Computing the Past: Computer Application and Quantitative methods in Archaeology: Aarhus, Denmark, Aarhus University Press, pp. 285–291.
  3. Oswin, J., {2018}. The Roman Baths, Bath Archway Project Geophysical Survey, January 2018.
  4. Pisani Sartorio, G., & Calza R., {1976}. “La villa di Massenzio sulla Via Appia: Il Palazzo - Le Opere D'Arte”, in Monumenti romani VI, Roma.

How to cite: Santarelli, R., Bianchini Ciampoli, L., and Benedetto, A.: The use of GPR in Archaeology: the structural detailing of buried roman baths, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7042, https://doi.org/10.5194/egusphere-egu2020-7042, 2020.

EGU2020-20872 | Displays | GI2.5

The Use of Ultrasonic Tomography for the Non-destructive Assessment of Tree Trunks

Amir M. Alani, James Chambers, Paul Melarange, Livia Lantini, and Fabio Tosti

Assessing internal decay in tree trunks can be of crucial importance for industrial, environmental and public safety reasons [1]. To this effect, non-destructive testing (NDT) methods can provide information on the structural condition of trees with minimum intrusion. In this work, authors have analysed the capabilities of ultrasonic tomography in evaluating the internal structure of living trees, with a special focus on the identification of internal decay areas and tree bark inclusions.

The presented ultrasonic tomography provides an image of the distribution of the ultrasonic velocity of propagation within the investigated section of a mature horse chestnut (Aesculus hippocastanum). This technique has proven its viability to detect fungal decomposition [2]. However, there exist some open issues with regard to: a) the coupling of the transducers to the tree, b) the anisotropy of the wood, c) the signal attenuation and the resolution of the tomographic inversion. To overcome these challenges, research is underway to explore the integration and new data-fusion strategies with other NDT methods, such as ground penetrating radar (GPR), which have proven their effectiveness within this area of endeavour [3].

Within this context, data have been obtained from a “diseased” horse chestnut tree located at the Kensington Gardens – The Royal Parks – in London, UK, using two different ultrasonic equipment, i.e., the PICUS Sonic Tomograph and the Arbotom Sonic Tomograph. After compilation of data, the tree was felled and cut at the two sections where ultrasonic tomography tests were performed. In more detail, 12 sensors were arranged around the perimeter of the tree in compliance with the manufacturer’s recommendations concerning the inspection methodology (sensors installed within the bark of the tree without any intrusion to the core of the tree). The adopted methodology takes to account the shape and size of the trunk [1]. The processed data were mapped against the cut sections of the tree for validity purposes.   

Results presented in this abstract are part of a major ongoing research project that the authors have undertaken for the last three years.

 

Acknowledgements

The authors would like to express their sincere thanks and gratitude to the following trusts, charities, organisations and individuals for their generosity in supporting this project: Lord Faringdon Charitable Trust,The Schroder Foundation,Cazenove Charitable Trust,Ernest Cook Trust,Sir Henry Keswick,Ian Bond, P.F. Charitable Trust,Prospect Investment Management Limited,The Adrian Swire Charitable Trust,The John Swire 1989 Charitable Trust,The Sackler Trust,The Tanlaw Foundation, and The Wyfold Charitable Trust. We would like to thank also Ian Rodger – Royal Parks Arboricultural Manager– for providing us with the tested tree. This paper is dedicated to the memory of our colleague and friend Jonathan West, one of the original supporters of this research project.

 

References

[1] Gilbert, G.S. et al. (2016). Use of sonic tomography to detect and quantify wood decay in living trees, Applications in Plant Sciences 4(12): 1600060.

[2] Bucur, V. Acoustics of Wood. CRC Press Inc., Boca Raton,Argentina (1995).

[3] Alani, A.M. et al. (2019). The Use of Ground Penetrating Radar and Microwave Tomography for the Detection of Decay and Cavities in Tree Trunks. Remote Sensing 11: 2073.

How to cite: Alani, A. M., Chambers, J., Melarange, P., Lantini, L., and Tosti, F.: The Use of Ultrasonic Tomography for the Non-destructive Assessment of Tree Trunks, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20872, https://doi.org/10.5194/egusphere-egu2020-20872, 2020.

EGU2020-21132 | Displays | GI2.5

Surface Electrical Resistivity Tomography: a non-invasive tool to assess the compaction in paddy soils

Bianca Ortuani, Camilla Negri, and Arianna Facchi

Soil compaction has direct effects on soil physical properties (increase in soil strength, bulk density, decrease in total porosity, soil aeration, water infiltration rate, and saturated hydraulic conductivity) often reducing root penetration and plant growth, thereby causing a reduction of soil productivity. However, the presence of compacted layers in rice paddy fields increases the efficiency of the traditional flooding irrigation method. For this reason, the use of monitoring tools to detect depth,  thickness and lateral continuity of compacted soil layers in paddy fields is of crucial importance for the assessment of their irrigation efficiency. Electrical Resistivity Tomography (ERT) is a non-invasive geophysical method which allows to detect soil horizons with different degrees of compaction. Particularly, arrays constituted of short electrodes spaced a few centimeters can be used to investigate with high vertical resolution the soil profile.

In a sandy loam paddy field located in the Lomellina region (PV; RISTEC project, RDP-EU, Lombardy Region), a surface ERT survey was conducted in February 2019 to verify the effectiveness of this technique in assessing soil compaction. The ERT was carried out with Wenner arrays of 48 electrodes spaced 0.1 m along a 5 m transect, to investigate the soil profile up to about 1 m depth in proximity of a soil profile trench dug for soil description and sampling. The results of the traditional soil survey (accurate description of soil horizons, including the compacted layer) were considered as reference data to evaluate the reliability of ERT results. During the ERT survey, soil samples were collected at different depths and distances along the ERT transect: texture, bulk density and porosity were successively measured in laboratory. Moreover, the volumetric soil water content was measured with a probe (ML2 ThetaProbe, Delta-T Devices). Main results show that the correlation between electrical resistivity (ER) and bulk density, soil porosity and volumetric water content is well in line with those observed in recent studies. Data points in the scatter plots are clustered based on the bulk density values; particularly, the cluster corresponding to high bulk density values (i.e. compacted soil) includes the measurement points at the depth where the ERT image shows a greater ER gradient. This depth also corresponds to the compacted layer observed during the investigation of soil profile with traditional methods. These results confirm that compacted layers can be effectively detected in ERT images by identifying depths characterized by higher ER gradients in soils with a relatively homogeneous soil texture. Consequently, an integrated approach combining surface ERT and soil sampling with a hand auger at a few depths to check the texture homogeneity and eventually collect a few soil samples for further analysis (e.g., bulk density, volumetric water content, soil hydraulic conductivity) could be explored to assess the presence and continuity of compacted layers in paddy soils, instead of intensive and extremely invasive surveys.

How to cite: Ortuani, B., Negri, C., and Facchi, A.: Surface Electrical Resistivity Tomography: a non-invasive tool to assess the compaction in paddy soils , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21132, https://doi.org/10.5194/egusphere-egu2020-21132, 2020.

EGU2020-19697 | Displays | GI2.5

Tree Monitoring Using Ground Penetrating Radar: Two Case Studies Using Reverse-Time Migration

Iraklis Giannakis, Fabio Tosti, Lilong Zou, Livia Lantini, and Amir M. Alani

  Non-destructive testing (NDT) for health monitoring of trees is a suitable candidate for detecting signs of early decay [1]. Recent developments [2,3,4] have highlighted that ground-penetrating radar (GPR) has the potential to provide with a robust and accurate detection tool with minimum computational and operational requirements in the field. In particular, a processing framework is suggested in [2] that can effectively remove ringing noise and unwanted clutter. Subsequently, an arc length parameterisation is employed in order to utilise a wheel-measurement device to accurately position the measured traces. Lastly, two migration schemes; Kirchhoff and reverse-time migration, are successfully applied on numerical and laboratory data in [3].

  In the current paper, the detection scheme described in [2,3] using reverse-time migration is tested in two case studies that involve diseased urban trees within the greater London area, UK (Kensington and Gunnersbury park). Both of the trees were cut down after the completion of the measurements and furthermore cut into several slices to get direct information with regards to their internal structure. The processing scheme described in [3,4] managed to adequately detect the internal decay present in both trees. The aforementioned case studies provide coherent evidences to support the premise that GPR is capable of detecting decay in diseased trunks and therefore has the potential to become an accurate and efficient diagnostic tool against emerging infectious diseases of trees.

 

Acknowledgements

The authors would like to express their sincere thanks and gratitude to the following trusts, charities, organizations and individuals for their generosity in supporting this project: Lord Faringdon Charitable Trust, The Schroder Foundation, Cazenove Charitable Trust, Ernest Cook, Sir Henry Keswick, Ian Bond, P. F. Charitable Trust, Prospect Investment Manage- ment Limited, The Adrian Swire Charitable Trust, The John Swire 1989 Charitable Trust, The Sackler Trust, The Tanlaw Foundation and The Wyfold Charitable Trust.

  This paper is dedicated to the memory of Jonathon West, a friend, a colleague, a forester, a conservationist and an environmentalist who died following an accident in the woodland that he loved.

 

References

[1] P. Niemz, D. Mannesm, ”Non-destructive testing of wood and wood-based materials,” J. Cult. Heritage, vol. 13, pp. S26-S34, 2012.

[2] I. Giannakis, F. Tosti, L. Lantini and A. M. Alani, "Health Monitoring of Tree Trunks Using Ground Penetrating Radar," IEEE Transactions on Geoscience and Remote Sensing, vol. 57, no. 10, pp. 8317-8326, 2019.

[3] I. Giannakis, F. Tosti, L. Lantini and A. M. Alani, "Diagnosing Emerging Infectious Diseases of Trees Using Ground Penetrating Radar," IEEE Transactions on Geoscience and Remote Sensing, Early Access, doi: 10.1109/TGRS.2019.2944070 

[4] A. M. Alani, F. Soldovieri, I. Catapano, I. Giannakos, G. Gennarelli, L. Lantini, G. Ludeno and F. Tosti, “The Use of Ground Penetrating Radar and Microwave Tomography for the Detection of Decay and Cavities in Tree Trunks,” Remote Sensing, vol. 11, no. 18, 2019.

How to cite: Giannakis, I., Tosti, F., Zou, L., Lantini, L., and Alani, A. M.: Tree Monitoring Using Ground Penetrating Radar: Two Case Studies Using Reverse-Time Migration, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19697, https://doi.org/10.5194/egusphere-egu2020-19697, 2020.

GI2.8 – Geoscience problems related to massive release of radioactive materials by nuclear accidents and other human activities

EGU2020-10066 | Displays | GI2.8

Radionuclide atmospheric transport after the forest fires in the Chernobyl Exclusion zone in 2015-2018: An impact of the source term parameterization and input meteorological data on modeling results

Mykola Talerko, Ivan Kovalets, Shigekazu Hirao, Mark Zheleznyak, Yuriy Kyrylenko, Tatiana Lev, Vladimir Bogorad, and Serhii Kireev

The highly contaminated Chernobyl exclusion zone (ChEZ) still remains a potential source of the additional atmosphere radioactive contamination due to forest fires there. The possible radionuclide transport outside the ChEZ in the direction of populated regions (including Kyiv, 115 km from the ChEZ borders) and its consequences for people health is a topic of a constant public concern in Ukraine and neighboring countries. The problem of additional radiation exposure of fire-fighters and other personnel within the ChEZ during forest fires is actual too. The reliable models of radionuclide rising and following atmospheric transport, which should be integrated with data of stationary and mobile radiological monitoring, are necessary for real-time forecast and assessment of consequences of wildland fires.

Results of intercomparison of models developed within the set of the national and international projects are presented, including: i) the point source term model of Atmospheric Dispersion Module (ADM) of the real -time online decision support system for offsite nuclear emergency – RODOS, which development was funded by EU; ii) the specialized new tool for modeling radionuclide dispersion from the polygons of the fired areas using the Lagrangian model LASAT incorporated into RODOS system; iii) the Lagrangian-Eulerian atmospheric dispersion model LEDI using a volume source term and including a module for calculation of  parameters of a convective plume  formed over a fire area; iv) the Lagrangian model of Fukushima University. All atmospheric transport models use the results of the numerical weather forecast model WRF as the input meteorological information.

The models evaluation was carried out using the measurement data during large wildland fires occurred in ChEZ in 2015 and June 2018, including the 137Cs and 90Sr volume activity measured with the monitoring network within the Zone and results due to special measurements with a mobile radiological laboratory outside it.

The sensitivity of atmospheric transport modeling results was estimated to: 1) internal parameterization of different models, first of all, parameterization of the value of the deposited radionuclide fraction re-entering into the atmosphere during forest fires, 2) different parameterization of the source term formed due to the forest fire; 3) quality of input meteorological information, including the space and time step of the used WRF model grid, and the impact of chosen parameterization of some WRF modules (e.g. the atmospheric boundary layer module) on the atmospheric transport model results. Additionally, results of forest fires consequences modeling was compared which were obtained with different sets of input meteorological data: the WRF forecast of metrological fields (on-line calculations) and the similar WRF calculations on the base of objective analysis results.

How to cite: Talerko, M., Kovalets, I., Hirao, S., Zheleznyak, M., Kyrylenko, Y., Lev, T., Bogorad, V., and Kireev, S.: Radionuclide atmospheric transport after the forest fires in the Chernobyl Exclusion zone in 2015-2018: An impact of the source term parameterization and input meteorological data on modeling results, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10066, https://doi.org/10.5194/egusphere-egu2020-10066, 2020.

In case of an accidental radioactive release, the Institute for Radiological Protection and Nuclear Safety (IRSN) uses atmospheric dispersion models to assess radiological consequences for human health and environment. The accuracy of the models’ results is highly dependent on the meteorological fields and the source term, including the location, the duration, the magnitude and the isotopic composition of the release.

Inverse modelling methods have proven to be efficient in assessing the source term. Variational deterministic inverse methods have been used on the Fukushima accident and are suitable in operational use since they are able of quickly providing an optimal solution.
However the quantification of the uncertainties of the source term assessed is usually not easily accessible. In
contrast, Bayesian inverse methods are developed in order to efficiently sample the distributions of the variables of the source, thus allowing to get a complete characterisation of the source.

In this study, we propose to tackle the Bayesian inference problem through two types of sampling methods: Monte Carlo Markov Chains methods (MCMC) with the parallel tempering algorithm and Stein variational gradient descent. The distributions of the control variables associated to the source and the observations errors are presented. To better quantify observations errors, different approaches based on the definition of the likelihood, the reduction of the number of observations and the perturbation of the meteorological fields and dispersion model parameters are implemented.

These different methods are applied on two case studies: the detection of Ruthenium 106 of unknown origin in Europe in autumn 2017 and the accidental release of Selenium 75 from a nuclear facility in Mol (Belgium) in May 2019. For both of these events, we present a posteriori distributions enable to identify the origin of the release, to assess the source term and to quantify the uncertainties associated to the observations, the dispersion model and meteorological fields. Finally, we show that the Bayesian method is suitable for operational use.

How to cite: Dumont Le Brazidec, J., Bocquet, M., Saunier, O., and Roustan, Y.: Bayesian inference and uncertainty quantification for source reconstruction of radionuclides release: application to recent European radionuclide detection events, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-15257, https://doi.org/10.5194/egusphere-egu2020-15257, 2020.

Many efforts have been devoted to estimate the release rate of the radionuclide emission in the Fukushima Daiichi nuclear accident using regional scale observations. Because of the radioactive decay, regional scale observations may not provide information of short-lived radionuclides, which contributes the majority of radiation exposure in the early stage. In this study, the local-scale gamma dose rates data were used to estimate the atmospheric release rates of both long- and short-lived radio nuclides.The proposed method uses reactor physics to obtain an a priori radionuclide composition and a reverse source term estimate as an a priori release rate. A weighted additive model is developed, which uses the local-scale gamma dose rates to handle the conflicts between the two priors and to simultaneously incorporate them into the source inversion. The proposed method is validated against both the local-scale gamma dose rates and the regional concentration measurements of Cs-137. The results prove that the retrieved a posteriori source term combines the advantages of both priors and substantially improves the predictions of the on-site gamma dose rates. Given a detailed priori release rate, this approach also improves the regional predictions of both airborne and deposited Cs-137 concentrations.

How to cite: Fang, S., Li, X., and Zhuang, S.: Release rate estimation of both long- and short-lived radionuclides for the Fukushima Daiichi nuclear accident based on local-scale observations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-233, https://doi.org/10.5194/egusphere-egu2020-233, 2020.

EGU2020-7186 | Displays | GI2.8

Equilibrium and kinetic approaches for modelling sorption processes on radiocesium soil profiles in Fukushima prefecture

Hamza Chaif, Frederic Coppin, Aya Bahi, and Laurent Garcia-Sanchez

The study of radionuclides (RNs) retention processes onto the solid phases is a key element for the prediction of their transfer in soils. It allows a better quantification of the persistence of radioactive contaminants on the soil surface, their availability for root uptake and their vertical transfer towards groundwater.

This work addresses the comparison between equilibrium and kinetic hypotheses of sorption processes on real post-accidental soil contamination profiles. The equilibrium-kinetic (EK) sorption model was selected as a non-equilibrium parameterization embedding the Kd approach. It supposes the existence of two types of sorption sites. The first sites are at equilibrium with solution, whereas for the second sites, kinetics of the sorption and desorption are taken into consideration.

We focused our study on four 137Cs soil contamination profiles measured in a cedar stand 35 km northwest of the Fukushima Dai-ichi Nuclear Power Plant. Profiles were sampled at four different dates (between 2013 and 2018) by measuring 137Cs activity in both organic (humus + litter layer) and mineral soil layers reaching a maximum depth of 20cm.

To successfully simulate the 137Cs transfer throughout these soil profiles, the input flux at the mineral soil surface was reconstructed from monitored throughfall, stemflow and litterfall fluxes in the same forest stand from July 2011 to November 2016 crossed with initial deposit and dynamic of the organic layer activity.

The EK model reproduced the measured contamination profiles slightly better than the fitted Kd model. While both models were able to reproduce the overall vertical distribution throughout the profiles, the persistent contamination at the surface was closer to the measured value with the EK approach. Additionally, the fitted Kd parameters (2000 L/kg to 6500 L/kg depending on the parcel) were considerably higher than the recommended value by The IAEA for organic soils (270 L/kg). When used, this recommended Kd value produced profiles with considerably faster transfer rate between layers and shorter persistence of the contamination at the surface.

To further distinguish the models behaviors, long term simulations were conducted. EK hypotheses induced much longer residence time of the contamination at the soil surface. For instance, by 2030, the EK approach predicted that 75 % of the contamination still remained in the 0-2 cm layer due to the slow desorption rate, whereas the Kd approach predicted it to be around 51 %. This fraction becomes even smaller (8 %) when using the Kd value (270 L/kg) recommended by the IAEA for organic soils.

These results prove that the choice of the sorption model is critical in post-accidental situations. An equilibrium approach, especially when using recommended parameter values, can result in an underestimation of the RNs residence time in the surface. Whereas a kinetic approach, by distinguishing different sorption and desorption rates, is able to reproduce the slow evolution of 137Cs soil profiles with time that is already observed in the case of Chernobyl contaminated areas 30 years after the accident.

How to cite: Chaif, H., Coppin, F., Bahi, A., and Garcia-Sanchez, L.: Equilibrium and kinetic approaches for modelling sorption processes on radiocesium soil profiles in Fukushima prefecture, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7186, https://doi.org/10.5194/egusphere-egu2020-7186, 2020.

EGU2020-5844 | Displays | GI2.8

A study of Cs-137 and Sr-90 distribution in the soil and vegetation cover of elementary landscape-geochemical systems in the zone of the East Ural Radioactive Trace

Elena Korobova, Sergey Romanov, Oleg Tarasov, Vladimir Baranchukov, Victor Berezkin, Denis Dolgushin, Lyudmila Mikhailovskaya, Makar Modorov, and Vitaly Lukyanov

The first results of a detailed study of 137Cs and 90Sr distribution in elementary landscape-geochemical system (the top-slope-closing depression type, ELGS) are presented on the example of test sites located in the head zone of the East Ural Radioactive Trace formed during the Kyshtym accident in 1957. Field measurements were performed using modified Violinist-III field gamma-spectrometer [1] and the Kolibri spectrometric complex [2]; laboratory determination of 137Сs was made by Canberra gamma-spectrometer (HPGe detector). Field measurements were carried out along cross-sections and in a grid manner with a step of 1 and 5 m accompanied by a theodolite survey and soil core sampling at the selected points. The instrumental layer-by-layer determination of 90Sr activity in soil samples performed in field conditions by [2] was compared with the radiochemical measurement of the same samples in fractions of less than and more than 1 mm. The correlation between the obtained instrumental and radiochemical values for 90Sr activity equaled to r = 0.962 (n = 50). Spatial distribution of both 137Cs and 90Sr manifested itself in an specifically organized polycentric structure. Against the absence of a pronounced tendency for unidirectional redistribution of radionuclides from the top to the bottom, there was an ordered cyclic change in the activity of both 137Cs and 90Sr, which in our opinion reflected the unified mechanism of redistribution of substances in ELGS, where the relief is the main controller of water migration. Measurement of 90Sr activity in selected meadow plants proved an important role of species in radionuclide accumulation at the ELGS level: the maximum amount of 90Sr was found in nettle (Urtica dioica, 86 ± 19 kBq/kg dw, n = 9), the minimum - in bluegrass (Poa sp., 13.8 ± 1.2 kBq/kg dw, n = 19). The revealed features of spatial structure of 137Cs and 90Sr are believed to mark the general tendencies of substances redistribution in ELGS, which seems important for studying soil formation, environmental monitoring and optimization of soil fertilizing.

The study was supported by the RFBR grant No. 19-05-00816.

References

1. Romanov S.L., Korobova E.M., Samsonov V.L. Experience in using the upgraded VIOLINIST-III instrument in field radioecological research //Yadernyye izmeritel'no-informatsionnyye tekhnologii. 2011, 3 (39), 56-61.

2. Potapov V.N. et al. Development of Portable Beta Spectrometer for Sr-90 Activity Measurements in Field Conditions and Its Application in Rehabilitation Activities at RRC Kurchatov Institute.WM’06 Conference, February 26 - March 2, 2006, Tucson, AZ [on line] http://www.wmsym.org/archives/2006/pdfs/6133.pdf.

How to cite: Korobova, E., Romanov, S., Tarasov, O., Baranchukov, V., Berezkin, V., Dolgushin, D., Mikhailovskaya, L., Modorov, M., and Lukyanov, V.: A study of Cs-137 and Sr-90 distribution in the soil and vegetation cover of elementary landscape-geochemical systems in the zone of the East Ural Radioactive Trace, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5844, https://doi.org/10.5194/egusphere-egu2020-5844, 2020.

EGU2020-2252 | Displays | GI2.8

Predicting Cs-137 Distribution Patterns from Soil Samples - The Relationships Between Topographic Parameters, Soil Properties, and Cs-137 Concentration Levels

Misa Yasumiishi, Taku Nishimura, Thomas Bittner, Jared Aldstadt, and Sean Bennett

Forests provide valuable water and nutrient resources to farming activities as well as places for various leisure activities. However, decontaminating forests in the aftermath of a massive radionuclide contamination event presents challenges because of the topography and the difficulty of collecting a large number of field samples. Achieving accurate remote measurements also can be hindered by the canopy cover. In Fukushima, Japan, where elevated radioactive fallout occurred following the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in March 2011, about 70 percent of the land is covered with forests. Soil samples collected in a forest in Iitate Village, Fukushima, beginning in 2016 through 2018 still contained an average 98200 Bq/kg of Cs-137 in the top 4 cm depth (std. dev. 114100 Bq/kg). Thus, decontamination and identification of Cs-137 distribution patterns in those forests is still a pressing issue. However, soil types in that region, 1000 mm annual precipitation with intense rain during typhoons, and microtopography have presented challenges to understanding how Cs-137 behaves in those forests.  In this study, six topographic parameters were computed from 1-m and 10-m resolution DEMs and the relationships between those parameters and soil water content and bulk density were systematically analyzed for their effects on Cs-137 concentration levels. As the first analytical step, correlation indices and the generalized additive models (GAM) analysis were conducted on those parameters. The results show that not all topographic effects are apparent in the correlation analysis, yet the results can be improved when mixed with other parameters in GAM models. Overall the effect of topographic parameters on Cs-137 levels is DEM resolution-dependent while individual soil properties indicate a strong relationship. Also, it was found that depending on the analysis depth, correlation levels and significance of those parameters in GAM models fluctuate. As the second step, Cs-137 levels were extrapolated to a larger area in the study site to understand further the connections between topography and soil properties. The results, including the limitations and proposals for future forest decontamination, will be presented in the session. Understanding how Cs-137 moves and accumulates in forests, especially immediately after contamination, is critical to avoiding the negative impacts on the environment by decontamination measures and to protecting lowlands from harmful radioactivity levels. This study contributes to the radionuclide research field by presenting an example of data analysis processes using field sampled data.

How to cite: Yasumiishi, M., Nishimura, T., Bittner, T., Aldstadt, J., and Bennett, S.: Predicting Cs-137 Distribution Patterns from Soil Samples - The Relationships Between Topographic Parameters, Soil Properties, and Cs-137 Concentration Levels, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2252, https://doi.org/10.5194/egusphere-egu2020-2252, 2020.

EGU2020-2787 | Displays | GI2.8

A coupled watershed-biogeochemical model to simulate dissolved and particulate 137Cs discharge from a forested catchment affected by the Fukushima accident

Kazuyuki Sakuma, Kazuya Yoshimura, Hiroshi Kurikami, Alex Malins, and Hironori Funaki

Dissolved 137Cs discharge represents approximately 30% of the total 137Cs discharge from the forested upstream catchment of the Ohta River in Fukushima, Japan [1]. It is thought that a major source of the dissolved 137Cs entering the river water may be leaching from forest litter [1]. A watershed simulation based on the distribution coefficient (Kd) that modelled water, sediment, and particulate and dissolved 137Cs transport could not reproduce the seasonal variability of the base flow dissolved 137Cs concentrations, nor the peaks in concentration that occurred during storms [2].

We developed a combined watershed-biogeochemistry model for simulating dissolved and particulate 137Cs discharge from forest catchments to describe the two phenomenon as mentioned above. A compartment model for the forest ecosystem was appended to the General-purpose Terrestrial fluid-Flow Simulator (GETFLOWS) watershed code. The compartment model included compartments for undecomposed and decomposed litter, with transfer from the former into the latter depending on temperature. A pathway for dissolved 137Cs input to forest streams was linked from the decomposed litter compartment.

The results from a simulation with the new simulation model reproduced the seasonal variability of dissolved 137Cs concentrations and the peaks occurring during storms. Therefore the new modelling results add weight to the theory that leaching from decomposed litter can input dissolved 137Cs concentrations in river water in Fukushima Prefecture. The developed model is expected to be useful for further explorations into factors affecting dissolved 137Cs input to river water in forested catchments.

 

[1]Tsuji et al., 2016. J. Geophys. Res. Biogeosci. 121, 2588-2599.

[2]Sakuma et al., 2018. J. Environ. Radioact. 184-185, 53-62.

How to cite: Sakuma, K., Yoshimura, K., Kurikami, H., Malins, A., and Funaki, H.: A coupled watershed-biogeochemical model to simulate dissolved and particulate 137Cs discharge from a forested catchment affected by the Fukushima accident, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2787, https://doi.org/10.5194/egusphere-egu2020-2787, 2020.

EGU2020-13220 | Displays | GI2.8 | Highlight

Temporal changes of the radiocesium activity concentration in river bottom sediment and suspended sediment in Eastern Japan

Yuichi Onda, Chen Tang, Xiang Gao, Yukio Takeuchi, Keisuke Taniguchi, Momo Kurihara, and Katsumi Hirose

We examined the temporal trend of Cs-137 concentration of river sediment and suspended sediment in Eastern Japan areas from September 2011 to January 2017. We used 716 monitoring data by the Ministry of the Environment from 461 sites and applied particle size correction to eliminate the influence of changes in particle size distribution in the concentration of Cs-137. Also, in some locations, we also compared the activity concentration of suspended sediment and dissolved water in Cs-137 and compared.    The results showed that Cs-137 concentration decreased through the study period in most sites, and the average declining, λ, is about 0.168 in the 2013-2018 period. In some sites increasing trend or larger rate of decline were found, but these locations are limited to lower contaminated catchments (less than 50k Bq/m2). The particle size corrected Kd value of the bottom sediment (Kd ac) shows around 10-4 to 10-5 Kg/L, but varied significantly where the initial catchment inventories are less than 50 kBq/m2. In most sites,  Cs-137 concentration on the particle size corrected Suspended sediment and bottom sediment show similar values, except for some specific sites (such as near the coast, etc).  These data imply that the activity concentration of dissolved Cs is important to control the rate and processes of interaction of dissolved radionuclides with the bottom sediment interface layer in the river environment affected by the Fukushima fallout.

How to cite: Onda, Y., Tang, C., Gao, X., Takeuchi, Y., Taniguchi, K., Kurihara, M., and Hirose, K.: Temporal changes of the radiocesium activity concentration in river bottom sediment and suspended sediment in Eastern Japan, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13220, https://doi.org/10.5194/egusphere-egu2020-13220, 2020.

EGU2020-3245 | Displays | GI2.8

Radiocesium wash-off, river transport and redistribution in fluvial system after the Fukushima Dai-ichi nuclear power plant accident

Aleksei Konoplev, Yoshifumi Wakiyama, Toshihiro Wada, Valentin Golosov, Maxim Ivanov, Mikhail Komissarov, Volodymyr Kanivets, Cameron Udy, Takuya Niida, Shota Moritaka, Misaki Usuki, Kenji Watanabe, Tsugiko Takase, Azusa Goto, Hirofumi Tsukada, and Kenji Nanba

Processes responsible for long-term changes in environmental radioactivity after the Fukushima accident are currently high on the agenda. Dynamics of particulate and dissolved radiocesium (r-Cs) has been studied on a number of water bodies, namely Abukuma River, Niida River and Maeda River, the dam reservoirs of Yokokawa (Ota River), Sakashita (Kuma River), Ogaki (Ukedo River) and Shinobu (Abukuma River) and four heavily contaminated irrigation ponds in Okuma town (Inkyozaka, Suzuuchi, Funasawa, Kashiramori). Water samples were collected for dissolved and particulate r-Cs analysis at multiple sites for these water bodies. Wash-off from slopes of contaminated catchments and river transport are key long-term pathways for radionuclide dispersal from contaminated areas after the Fukushima accident. The climate and geographical conditions for the Fukushima Prefecture of Japan are characterized by relatively high annual precipitation (1300-1800 mm/year) and steep slopes which promote higher erosion and higher particulate r-Cs wash-off. At the same time, the r-Cs distribution coefficient Kd in Fukushima rivers was found to be at least an order of magnitude higher than the corresponding values for Chernobyl-derived r-Cs and r-Cs resulting from nuclear weapon tests (NWT) in European rivers. The normalized dissolved wash-off coefficient for Fukushima river watersheds, based on the measured dissolved r-Cs activity concentrations was found to be 1-2 orders of magnitude lower than those for Chernobyl and NWT fallout. In the irrigation ponds r-Cs showed a persistent behavior and was characterized by regular seasonal variations: r-Cs concentrations tend to grow during summer and decrease during winter. Speciation analysis for Okuma ponds showed a much higher exchangeability of r-Cs in bottom sediments than catchment soils. Several methodologies to collect water samples and to separate the particulate and dissolved fractions have been used and showed comparable results for all water bodies under study. For all rivers, reservoirs, and ponds higher values of Kd(r-Cs) have been confirmed when compared with Chernobyl-derived r-Cs in European water bodies. Some observations demonstrated remobilization of r-Cs at river mouths compared to upstream sections which could be explained by the change of river water hydrochemistry from upstream to the mouth, specifically a substantial increase in the concentration of major r-Cs competing cations for selective sorption sites on the suspended matter. Some dam reservoirs and ponds were subjected to integrated suspended sediment sampling. For the dam reservoirs, the particulate r-Cs activity concentration has been found to be water depth-dependent. Sediment cores collected at eight sites along the Abukuma river floodplain in 2018 and during October-November 2019, right after Typhoon Hagibis occurred in the middle of October 2019, demonstrated substantial redistribution of r-Cs due to erosion and redeposition during heavy rainfall and extreme flood. Bottom sediments coring in the dam reservoirs allowed estimation of the average sedimentation rate in the reservoirs and the rate of r-Cs accumulation. This research was partially supported by the Japan Society for the Promotion of Science (JSPS), Grant-in-aid for Scientific Research (B) (18H03389), bilateral project No. 18-55-50002 of Russian Foundation for Basic Research (RFBR) and JSPS.

How to cite: Konoplev, A., Wakiyama, Y., Wada, T., Golosov, V., Ivanov, M., Komissarov, M., Kanivets, V., Udy, C., Niida, T., Moritaka, S., Usuki, M., Watanabe, K., Takase, T., Goto, A., Tsukada, H., and Nanba, K.: Radiocesium wash-off, river transport and redistribution in fluvial system after the Fukushima Dai-ichi nuclear power plant accident, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3245, https://doi.org/10.5194/egusphere-egu2020-3245, 2020.

EGU2020-13965 | Displays | GI2.8

Effect of decontamination on sediment discharge from mountain stream to river and cesium transfer in Yamakiya district

Fumiaki Makino, Yuichi Onda, Keisuke Taniguchi, Mitbaa Slim, Yoshifumi Wakiyama, Syohei Kozuka, Hiroaki Kato, and Sho Iwagami

After the accident of the Fukushima nuclear power plant, decontamination works had been conducted from 2013 to 2017 in the area of heavly contamination by fallout radionuclides. Although decontamination is conductive to decrease the air dose rate, associated disturbances of soil, such as scraping, reversal tillage, and soil dressing. These decontamination works, in turn, could increase the sediment discharge to downstream, but no studies are available on the effect of the decontamination in upstream headwaters that affects sediment discharge in rivers. Furthermore, decontamination has been carried out in the target area, the Yamakiya area, from 2013, and decontamination has been completed in the spring of 2016, decontamination work has been completed in 2017, and the residents have been returned. The sediment runoff due to human activities can be different from the sediment runoff due to decontamination.

The purpose of this study was to study the relationship between sediment dynamics and Cs dynamics due to decontamination, and the changes in sediment dynamics due to the return of residents. Observations and historical data were analyzed at Iboishi mountain in the forest and the middle stream of Kuchibuto. We have been monitoring suspended sediment Cs-137 concentration, water runoff, and suspended sediment runoff since 2014 at the middle point of the Kuchibuto River and since 2013 at Mt.Iboishi. The slope of the approximation line was compared with the LQ curve for comparison of the amount of sediment runoff. In the middle of the Kuchibuto river, it was 1.54 in 2014, 2.28 in 2015, 2.12 in 2016, 0.164 in 2017, and 0.189 in 2018. At Iboishi mountain in the forest, it was 1.72 in 2014, 0.947 in 2015, 1.39 in 2016, 0.219 in 2017, and 1.15 in 2018. The same tendency was shown in the slopes of the LQ curves in the middle part of the Kuchibuto river and the Iboishi mountain in the forest area. The Cs concentration was high until November 2015, but since then, the Cs concentration has decreased. These results suggest that the increased sediment discharge due to decontamination of the forest area affected the sediment discharge in the middle stream of the Kuchibuto River.

How to cite: Makino, F., Onda, Y., Taniguchi, K., Slim, M., Wakiyama, Y., Kozuka, S., Kato, H., and Iwagami, S.: Effect of decontamination on sediment discharge from mountain stream to river and cesium transfer in Yamakiya district, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13965, https://doi.org/10.5194/egusphere-egu2020-13965, 2020.

EGU2020-12301 | Displays | GI2.8

Mass balance of radiocaesium derived from Fukushima accident and estimation of latest fluxes among atmosphere, land and ocean

Michio Aoyama, Daisuke Tsumune, Yayoi Inomata, and Yutaka Tateda

Regarding with amount of movement of 137Cs from domain to domain for several years after the accident, we also evaluated that the amount of 137Cs transported by the rivers might be 40 TBq which is corresponding to less than 1.3 % of deposited 137Cs. For resuspension, the annual deposition of 137Cs at Okuma during the period from 2014 to 2018 means that 4 TBq year-1to 10 TBq year-1should be amount of resuspension from land to atmosphere and this amount correspond to 0.1 % to 0.3 % of total deposition of 137Cs on land in Japan. The 137Cs activity concentration at 56N canal in 2016-2018 correspond to 137Cs discharge of 0.73 TBq year-1to 1.0 TBq year-1from FNPP1 site to open water. The integrated amount of FNPP1 derived 137Cs that entered the Sea of Japan, SOJ, until 2017 was 0.27 ± 0.02 PBq, which is 6.4 % of the estimated total amount of FNPP1-derived 137Cs in the STMW in the North Pacific. The integrated amount of FNPP1-derived 137Cs that returned to the North Pacific Ocean through the Tsugaru Strait from SOJ was 0.11 ± 0.01 PBq, 42 % of the total amount of FNPP1-derived 137Cs transported to the SOJ. As a result of decontamination works, 134 TBq of 137Cs was removed from surface soil until February 2019 which correspond to 4 % of deposited 137Cs on land in Japan. Therefore, the largest transport amount of 137Cs was 270 ± 2 TBq from STMW in the North Pacific to SOJ until 2017, and the second largest was decontamination work by which work about 134 TBq was removed from surface soil on land until Feb. 2019. Fluvial transport by rivers contributed about 40 TBq since June 2011 until 2016.

How to cite: Aoyama, M., Tsumune, D., Inomata, Y., and Tateda, Y.: Mass balance of radiocaesium derived from Fukushima accident and estimation of latest fluxes among atmosphere, land and ocean, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12301, https://doi.org/10.5194/egusphere-egu2020-12301, 2020.

EGU2020-3826 | Displays | GI2.8

Intercomparison of atmospheric transport models using 1 km grid meteorological data for the Fukushima Daiichi Nuclear Power Plant Accident

Hiromi Yamazawa, Yousuke Sato, Tsuyoshi Sekiyama, Mizuo Kajino, Daisuke Goto, Yu Morino, Hiroaki Kondo, Arnaud Quérel, Sheng Fang, Masayuki Takigawa, Hiroaki Terada, Masanao Kadowaki, and Junya Uchida

  Following the previous atmospheric transport model intercomparison project (MIP2: Sato et al, 2018), a new project of model intercomparison (MIP3) has been conducted in which, out of 12 models in MIP2, 9 models are participating. The main aim of MIP3 is to examine the effects of using a refined meteorological data with a finer horizontal resolution of 1 km (Sekiyama et al., 2019). This paper describes outline of the preliminary results of MIP3.

  The horizontal distribution Cs-137 deposition in the eastern part of Honshu Island (the main island of Japan) calculated by the models were compared with the aerial survey results to find that the simple ensemble average of the 9 models was a little worse than that of the 12-model ensemble in MIP2 in terms of the statistical index RANK, which is the combination of the correlation coefficient, the fractional bias, the figure of merit in space and KPS. This slightly poorer performance is tentatively considered to be caused partially by the absence of three models which showed rather broad deposition patterns and by the underestimation in the Nakadori area (the middle part of Fukushima Pref.). However, in the sector in the northwestern direction from the accidental site which had the largest deposition, the deposition pattern simulated by the MIP3 ensemble, if compared with that of MIP2, is more consistent with the survey result. As for the atmospheric concentrations, although the model performance for the plumes that traveled over wider areas was found to be slightly poorer for MIP3 than MIP2, it was found that the MIP3 ensemble generally showed better performance for the plumes that affected the near area in the Hamadori area (the coastal part of Fukushima Pref.). The better performance of the MIP3 in this area can be attributed to the better representation of topography in the meteorological simulation.

How to cite: Yamazawa, H., Sato, Y., Sekiyama, T., Kajino, M., Goto, D., Morino, Y., Kondo, H., Quérel, A., Fang, S., Takigawa, M., Terada, H., Kadowaki, M., and Uchida, J.: Intercomparison of atmospheric transport models using 1 km grid meteorological data for the Fukushima Daiichi Nuclear Power Plant Accident, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3826, https://doi.org/10.5194/egusphere-egu2020-3826, 2020.

EGU2020-19840 | Displays | GI2.8

Re-assessment of airborne radiocesium re-suspended from contaminated ground surface after the Fukushima Nuclear Accident

Mizuo Kajino, Akira Watanabe, Yasuhito Igarashi, Yuji Zaizen, Takeshi Kinase, Masahide Ishizuka, and Kazuyuki Kita

Kajino et al. (2016) (doi:10.5194/acp-16-13149-2016) assessed emission, transport, and deposition of airborne radiocesium from contaminated ground surface after the Fukushima nuclear accident for the entire year of 2013 by using numerical simulation, a field experiment on dust emission flux in a contaminated area (town of Namie, Fukushima prefecture), and air concentration measurements inside (Namie) and outside the contaminated area (Tsukuba, Ibaraki prefecture). In this study, additional comparison of the simulation results has been made against the fallout measurements made in Fukushima (city of Fukushima) and Tsukuba and we found that our previous simulation results substantial underestimated the observed fallout by 2 to 3 orders of magnitude. The reason is, in the previous simulation, we assumed the size distributions of aerosols are in the submicron range, even though recent studies indicated that the aerosol sizes should be much larger (i.g., Kinase et al., 2018, doi:10.1186/s40645-018-0171-z, Igarashi et al., 2019, doi:10.1038/s41598-018-37698-x, and this study). By assuming larger sizes of Cs-bearing aerosols, the simulated concentrations and depositions in both Fukushima and Tsukuba were significantly improved. Consequently, the re-assessed emission flux was modified by several ten times more than that previously assessed by Kajino et al. (2016), which was 0.048% per year.

How to cite: Kajino, M., Watanabe, A., Igarashi, Y., Zaizen, Y., Kinase, T., Ishizuka, M., and Kita, K.: Re-assessment of airborne radiocesium re-suspended from contaminated ground surface after the Fukushima Nuclear Accident, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19840, https://doi.org/10.5194/egusphere-egu2020-19840, 2020.

EGU2020-22136 | Displays | GI2.8

Rain-enhanced/induced bioecological resuspension of radiocaesium in a polluted forest in Fukushima

Yasuhito Igarashi, Kazuyuki Kita, Takashi Kinase, Naho Hayashi, Masahide Ishizuka, Kouji Adachi, Motoo Koitabashi, and Yuichi Onda

It is the conventional understanding that rain removes aerosols from the atmosphere. However, the question of whether rain plays a role in releasing aerosols to the atmosphere has recently been posed by several researchers. In the present study, we show the additional evidence for rain-enhanced/induced aerosol emissions in a forest environment: the occurrence of radiocaesium-bearing aerosols in a Fukushima forest due to rain. We carried out general radioactive aerosol observations in a typical mountainous village area within the exclusion zone in Fukushima Prefecture to determine the impacts and major players of the resuspension of radiocaesium originally from the nuclear accident in March 2011. We also conducted sampling according to the weather (with and without rain conditions) inside a forest to clarify the atmospheric radiocaesium source from the polluted forest. Thus, we found that rain enhances/induces bursts of radiocaesium-bearing aerosols in forests in Fukushima. With further investigations, we found that the fungal spore sources of resuspended radiocaesium under rainy weather seemed to differ from those under nonrainy weather. Larger fungal particles (possibly conidia-ascospore) are probably emitted during rainy conditions than during nonrainy weather, suggesting that the splash generation by rain droplets is the major mechanism of the suspension of radiocaesium-bearing mould-like fungi. Fungal spores can function as ice and cloud condensation nuclei and cause allergies, and fungal inocula may have a significant impact on agriculture. Therefore, the present findings indicate that radiocaesium could be used as a tracer in research fields such as forest ecology, meteorology, climatology, public hygiene and agriculture.

How to cite: Igarashi, Y., Kita, K., Kinase, T., Hayashi, N., Ishizuka, M., Adachi, K., Koitabashi, M., and Onda, Y.: Rain-enhanced/induced bioecological resuspension of radiocaesium in a polluted forest in Fukushima, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22136, https://doi.org/10.5194/egusphere-egu2020-22136, 2020.

EGU2020-12465 | Displays | GI2.8

Effects of stemflow on infiltration flux of rainwater and dissolved Cs-137 to forest soil

Hikaru Iida, Hiroaki Kato, Tomoki Shinozuka, Satoru Akaiwa, Tatsuya Yokoyama, Sean Hudson, Janice Hudson, and Yuichi Onda

Stemflow takes important role on the hydrological and chemical cycling in the rhizosphere because it brings intensive rainwater input to forest soil and enhances downward infiltration of rainwater along tree root network to deep soil horizon. However, there are few studies on the effects of stemflow in rainwater infiltration mechanisms by collecting of soil water. In this study, stemflow and soil water near the tree roots (Rd : root downslope) and far from the trunk (Bt : between trees) are collected from a cedar forest in Namie Town, Fukushima Prefecture, Japan. Samples were collected from June 24 to December 11, 2019 with a total precipitation of 1100 mm during the period. Water volume and dissolved 137Cs concentration drived from the Fukushima Dai-ichi Nuclear Power Plant accident were measured. As a result, Rd which is located in neighbor of the trunk showed greater water infiltration flux and high dissolved 137Cs concentration. The average amount of infiltration water which was normalized for open rainfall depth during the whole sampling period was 1.4 times and 3.0 times larger at 5 cm and 20 cm depth for the Rd than the Bt, the average dissolved 137Cs concentration was 1.3 times and 1.7 times larger at 5 cm and 20 cm depth, respectively. This suggests that infiltration water flux and dissolved 137Cs concentration can be increased due to contribution of stemflow input at the base of tree trunk. To determine the role of stemflow on rainwater infiltration flux and the concentration of dissolved elements in the rhzosphere, further analysis is required to clarify detailed infiltration mechanisms by using multiple tracer techniques such as stable isotopic composition of water and by collecting root oriented preferential flow.

How to cite: Iida, H., Kato, H., Shinozuka, T., Akaiwa, S., Yokoyama, T., Hudson, S., Hudson, J., and Onda, Y.: Effects of stemflow on infiltration flux of rainwater and dissolved Cs-137 to forest soil, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12465, https://doi.org/10.5194/egusphere-egu2020-12465, 2020.

EGU2020-6634 | Displays | GI2.8

Vertical profiles of Cs-137 in soil of the Matua Island ( the Central Kuril Islands, Russia) in 2017

Borisov Alexander, Andrey Ivanov, and Vitaly Linnik

The 2011 Fukushima-Daiichi nuclear power plant (FDNNP) accident resulted in the atmospheric releases of large quantities of man-made radionuclides. According to [1], Matua Island, located at a distance of more than 1000 km from FDNPP, was also subjected to minor radioactive contamination. Matua Island, 52.6 sq.km, a recent volcano with the highest point of 1446 m a.s.l. is located in the center of the Kuril Islands Arc. Volcanic soils are formed on stratified gravelly-stony tephra more than 60 cm thick, underlain by thin layers of volcanic slags. The latest catastrophic eruption which changed the landscape of the island occurred in 2009.

Studies of the vertical distribution of the Cs-137 in soils were carried out on four landscape catenas. The length of the catenas from the sea shore deep into the island ranged from 700 m (maximum height a.s.l.  70 m) to 3.3 km (height a.s.l.  450 m).

Soil core samples were taken in  summer 2017 at a depth of tephra, which was located at a depth of 10 to 25 cm. Soil was sliced into separate layers with a step of 2 to 5 cm.

The measurement activity concentrations of the Cs-137 in the soil samples were carried out on a low-background gamma spectrometer Canberra Industries.  The counting time  was fixed not less than 24 h to ensure that the statistical measurement error is small.

Cs-134, the «Fukushima” fallout marker, due to the decay, was not detected. Therefore, it is difficult to accurately assess the Cs-137 contribution from the FDNNP accident from a global fallout.

The vertical distribution of Cs-137 is characterized by extreme heterogeneity, which reflects both the primary fallout conditions and the landscape conditions of the likely lateral redistribution. For сatena 1 with a length of 1 km and an altitude  of 400 m, the number of pickets (P0, P1, etc. – the numbering of pickets goes downhill), the specific activity of Cs-137 (Bq/kg) and the depth of the layer (cm) are given as follows: P0-27 Bq/kg (2-4 cm); P1 - 64 Bq/kg (6-8 cm); P2 – 70 Bq/kg (8-10 cm); P3 - 53 Bq/kg (4-6 cm); P4 - 15 Bq/kg (0-5 cm).  Similar spatial  heterogeneity of the specific activity of Cs-137 and its depth penetration was also found for catena 3 with a length of 1250 m and a height of 75 m (the numbering of pickets goes up the slope): P1-137 Bq/kg (17-20 cm); P2-76 Bq/kg (0-5 cm); P3 - 35 Bq/kg (0-4 cm); P4 - 43 Bq/kg (3-6 cm); P6 – 24 Bq/kg (5-10 cm).

The distribution of Cs-137 in individual soil layers was used to evaluate the empirically found shapes of the vertical profiles of radionuclide concentration. Cs-137 is believed here to be a  very valuable tracer  that  can be used to test  variability of vertical geochemical migration in Matua  landscapes.

[1]. Ramzaev V.P., Barkovsky A.N., Gromov A.V., Ivanov S.A., Kaduka M.V. Fukushima fallout in Sakhalin Region, Russia, part 1: 137Cs and 134Cs in grassland soils. Radiation Hygiene, 2018, Vol. 11, No. 1, pp. 25-42.

How to cite: Alexander, B., Ivanov, A., and Linnik, V.: Vertical profiles of Cs-137 in soil of the Matua Island ( the Central Kuril Islands, Russia) in 2017 , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6634, https://doi.org/10.5194/egusphere-egu2020-6634, 2020.

EGU2020-4197 | Displays | GI2.8

Development of a method to identify alpha-emitter-bearing-particles in soil samples collected in the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) area

Aurélie Diacre, Anne-Lare Faure, Agnès Moureau, Olivier Marie, Nina Griffiths, Olivier Evrard, and Fabien Pointurier

The Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident that occurred in March 2011 released significant quantities of radionuclides in the environment. So far, most of the research focused on radio-cesium and rarely on actinides. Until now, most of the studies on uranium and plutonium released by FDNPP were conducted on bulk environmental samples (soil, sediment, biota, etc.) and rarely on individual particles The investigation of individual particles allows working on the FDNPP signature alone compared to studies of bulk material which may also incorporate the signature of global fallout. Accordingly, the objective of the current research is to identify and characterize actinide-bearing particles in soil samples collected in the vicinity of FDNPP to get a better understanding of their formation mechanisms and of their fate in the environment. In order to identify and locate actinide-bearing particles in soil samples, we developed and implemented a method based on alpha-autoradiography (Jaegler et al., 2019), which allows identifying and locating specifically alpha-emitters, including plutonium isotopes 239Pu, 240Pu and 241Pu using a CR39 SSNTD device (Solid State Nuclear Tracks Detector).

Before alpha-autoradiography samples were dried, grinded with an agate mortar and sieved to several cutoffs: 1mm, 700µm, 400µm, 200µm, 100µm and 63µm. Cutoffs were chosen according to the sizes of actinide-bearing particles detected by Satou et al (2018). The absence of significant loss of uranium particles by the sieving process was demonstrated by the analysis of a test soil sample with a 137Cs activity below 650 Bq/kg spiked with depleted uranium reference particles. After sieving, the test sample was deposited onto a carbon planchet for secondary ion mass spectrometry analysis in order to determine the particle recovery yield.

Then, the detection of actinide-bearing particles by means of alpha autoradiography was performed on various soil samples collected in the vicinity of FDNPP. Longer exposure times logically improve the detection efficiency of alpha-emitters-bearing particles. However, the exposure time should not exceed two months to limit the impact of emissions from naturally-occurring alpha-emitters.

We will present here the first results of detection of alpha-emitting particles in the analyzed soil samples.  Relative impacts of naturally-occurring alpha-emitters (234U/238U, 235U, 232Th and daughter nuclides) and of plutonium isotopes on alpha-radiography trace observation will be discussed.

The next steps of this study will be to develop and implement methods to sample and isolate alpha-emitting particles from the soil matrix and to characterize them in size, morphology, elemental and isotopic compositions. Full characterization of individual particles will be very helpful to determine their origin and to provide an understanding of their formation process and to determine their mobility and life-duration in the environment.

References:

How to cite: Diacre, A., Faure, A.-L., Moureau, A., Marie, O., Griffiths, N., Evrard, O., and Pointurier, F.: Development of a method to identify alpha-emitter-bearing-particles in soil samples collected in the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) area, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4197, https://doi.org/10.5194/egusphere-egu2020-4197, 2020.

EGU2020-22438 | Displays | GI2.8

Evaluation of the changes in the Radiocaesium Interception Potential (RIP) of Japanese and European soils based on their potassium content, mineralogy and agricultural zeolite amendments

Francesc Xavier Dengra i Grau, Tetsuya Eguchi, Arsenio Toloza, Erik Smolders, Sandor Tarjan, Takuro Shinano, Martin Gerzabek, Hans Christian Bruun Hansen, and Gerd Dercon

After the Fukushima Daiichi Nuclear Power Plant (FDNPP) aftermath in 2011, potassium addition has been increasingly valued as the most effective countermeasure for soil remediation of polluted sites. Potassium is a competing cation with caesium during plant root uptake. Recent studies have elucidated that potassium application can increase the Radiocaesium Interception Potential (RIP), a key parameter that determines the radiocaesium selectivity in soil and therefore its phytoavailability. The RIP is determined as the product of the distribution coefficient of caesium and the concentration of potassium in soil solution, considering the occupation in exchange regular sites but especially in the so-called frayed-edged of the 2:1 phyllosilicate layers of clay minerals, that account for most of the high-selectivity sites for caesium. In order to increase soil RIP, mineral amendments -especially zeolite- were applied in Japanese target fields as a major measure for safe agricultural production. In this study, we aimed at the determination of the RIP of Japanese and European soils with different clay mineralogy, as a key parameter for the solid-liquid distribution of radiocaesium in soils. To do so, we analysed the clay mineralogy of soils by X-Ray diffraction (XRD), as well as the solid and soil solution phases of five types of soils with different potassium fixing capacity by atomic absorption spectrometry (AAS) and ionic chromatography (IC), respectively. As potassium fixation varies among soils, we expected very different relationships between their potassium content and RIP. Their RIP was determined by spiking with 1-2 KBq of radiocaesium-134 prior to the use of thallium doped sodium iodine scintillator (NaI(Tl)). Both solid phase exchangeable caesium and soil solution caesium were analysed by inductively coupled plasma mass spectrometry (ICP-MS). Partial findings for Japanese soils showed a potassium fixing rate of approximately 93% for vermiculitic soils, while for imogolitic Andosols with low 2:1 phyllosilicate clay mineral content, only 17% of potassium addition was determined to be fixed. The fixation capacity for smectitic soils reached 57%. Furthermore, additional research is currently being done regarding RIP determination of several agricultural soils and with and without zeolite amendments. The final results will be shown in the EGU General Assembly 2020.

How to cite: Dengra i Grau, F. X., Eguchi, T., Toloza, A., Smolders, E., Tarjan, S., Shinano, T., Gerzabek, M., Bruun Hansen, H. C., and Dercon, G.: Evaluation of the changes in the Radiocaesium Interception Potential (RIP) of Japanese and European soils based on their potassium content, mineralogy and agricultural zeolite amendments, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22438, https://doi.org/10.5194/egusphere-egu2020-22438, 2020.

EGU2020-19250 | Displays | GI2.8

Distributed modeling of radionuclide washing out from the watersheds in solute and with suspended sediments: case studies Abukuma River, Fukushima Prefecture and Pripyat – Dnieper river system, Ukraine

Mark Zheleznyak, Oleksandr Pylypenko, Sergii Kivva, Kazuyuki Sakuma, Yasunori Igarashi, Yoshifumi Wakiyama, Aleksey Konoplev, and Kenji Nanba

The measurements of  137Cs concentration in the rivers of Fukushima prefecture demonstrate the more significant role of the fluxes of 137Cs adherent to the suspended sediments in comparison with the rivers contaminated after the Chernobyl accident. Therefore the forecasting of   137Cs  concentration during the floods requires to use the models of radionuclide wash-off from the watersheds with sediments.

Comprehensive modeling of radionuclide transport processes could be provided on the basis of the physically-based distributed models of hydrological and sediments transport processes. Such distributed models can describe soil erosion and sedimentation processes, as also exchange of the radionuclides between solute, suspended sediment and upper soil level.  We developed such type .model DSHVM-R based on the distributed hydrological- sediment transport model DHSVM of Washington University.  The model implementation for the experimental plots in Fukushima prefecture demonstrated a good possibility of the model for the analyses on the influence of the steepness of the watershed slopes and the intensity of the rainfall in the increased role of particulate 137Cs transport.  From another side,  the implementation of such a model for large river watershed required too large computational time and significant efforts for processing of the large sets of the distributed data still not available for all watersheds.

We developed model RETRACE _RS  that combines the simplicity of the watershed empirical models based on the washing -out coefficient approach with the possibility to use geographically distributed data of the radioactive fallout and  GIS layers for rivernets. The model RETRACE_RS is an extension of the model RETRACE _R  (Zheleznyak et al, 2010),  which code is integrated into the Hydrological Dispersion  Module of the Decision Support System RODOS.   RETRACE_R is based on the assumptions that the rate of the radionuclide wash- off from each elementary grid cell of the watershed can be calculated from precipitation rate and density of deposition in this cell through the “wash-off” coefficient Kw; and that the radionuclides washed out from the cell are transported without time delay to the nearest river channel cell - to the grid element of the 1-D river model RIVTOX as lateral inflow. In RETRACE _RS the possibility of RETRACE_R to simulate washing -out of the radionuclides from watershed to river in solute was extended by the fluxes of the particulate radionuclide transport calculated via the “ washing out coefficient for particulate radionuclide transport ” -Kss. The formula to calculate Kss values is based on the empirical relations for the particulate  137Cs transport in the rivers of Fukushima prefecture ( Sakuma et al, 2019). The model was tested on the basis of the measurements of 137Cs concentration in Abukuma river during the high floods in 2018-2019. The modeling system RETRACE_RS  - RIVTOX was validated also on the basis of the data sets of radionuclide transport in the Pripyat and Dnieper rivers. The system is testing for the prediction of aquatic radionuclide transport from the Chernobyl NPP area to the  Kyiv region during the extreme floods.

 

How to cite: Zheleznyak, M., Pylypenko, O., Kivva, S., Sakuma, K., Igarashi, Y., Wakiyama, Y., Konoplev, A., and Nanba, K.: Distributed modeling of radionuclide washing out from the watersheds in solute and with suspended sediments: case studies Abukuma River, Fukushima Prefecture and Pripyat – Dnieper river system, Ukraine , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19250, https://doi.org/10.5194/egusphere-egu2020-19250, 2020.

EGU2020-12477 | Displays | GI2.8

Plot-scale wash-off of Cesium-137 and Strontium-90 after three decades since the Chernobyl accident

Yoshifumi Wakiyama, Yasunori Igarashi, Yuichi Onda, Dmitry Samoilov, Hlib Lisovy, Volodymyr Demianovych, Gennady Laptev, Alexei Konoplev, Kenji Nanba, and Serhii Kirieiev

Long-term behaviors of Cesium-137 (137Cs) and Strontium-90 (90Sr) have been of great interest in Chernobyl and its downstream area. This study presents plot-scale observations of 137Cs and 90Sr wash-off in the Chernobyl exclusion zone since 2018 to date. Runoff plots were established on a pine forest in the Kopachi area (PF-KP), an abandoned farmland in the Korogod area (AF-KR) and a post wild fire territory in the Red Forest (WF-RF) in December 2017. Each runoff plot consists of eroding surface of 22.13 m length and 5 m width, a 30° V-notch weir with water level sensor for monitoring surface runoff and tanks for collecting runoff water and sediments. Since February 2018, runoff water and sediment samples trapped in the weir and tanks have been collected after rainfall events and analyzed for particulate 137Cs concentration, dissolved 137Cs concentration, and dissolved 90Sr concentration. Analyses of samples in 2, 4, and 3 wash-off events were completed for PF-KP, AF-KR, and WF-RF, respectively. The ash/litter on soil surface, soil of 0-1 cm depth, soil of 1-2 cm depth, and soil of 2-3 cm depth were sampled with a scraper plate and subject to measurements of 137Cs and 90Sr concentrations.  Total volume of surface runoff from PF-KP, AF-KR, and WF-RF were 0.97, 0.73, and 3.2 mm, respectively. Total sediment discharge from PF-KP, AF-KR, and WF-RF were 0.29, 0.015, 1.7 g m-2, respectively. The runoff and sediment discharge from PF-KP and WF-RF were mainly observed in summer and attributed to severe water repellency of the surface soils. Total particulate 137Cs wash-off from PF-KP, AF-KR, and WF-RF were 51, 0.082, 270 Bq m-2, respectively. Total dissolved 137Cs wash-off from PF-KP, AF-KR, and WF-RF were 7.4, 0.024, 9.8 Bq m-2, respectively. Total dissolved 90Sr wash-off from PF-KP, AF-KR, and WF-RF were 55, 0.31, 230 Bq m-2, respectively.  These results indicate that wild fire enhances surface runoff and sediment yield and result in greater wash-off of 137Cs and 90Sr. In comparisons between PF-KP and WF-RF, apparent Kd value for 137Cs at WF-RF was higher than at PF-KP. Ratio of dissolved 137Cs and 90Sr concentration to those in ash/litter layer at PF-KP was lower than those of WF-RF. The dissolution of these radionuclides into runoff water appeared to be restrained in the post wild-fire site.

How to cite: Wakiyama, Y., Igarashi, Y., Onda, Y., Samoilov, D., Lisovy, H., Demianovych, V., Laptev, G., Konoplev, A., Nanba, K., and Kirieiev, S.: Plot-scale wash-off of Cesium-137 and Strontium-90 after three decades since the Chernobyl accident , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12477, https://doi.org/10.5194/egusphere-egu2020-12477, 2020.

A large amount of radioisotopes of Ceasium (Cs) was released into the surrounding environment by the accident of the Fukushima Dai-ichi Nuclear Power Plant (1F) occurred in 2011, and some of them fell into land and sea. Since Cs is an element inside a group of alkali metals, radioisotopes of Cs are strongly sorbed by soil and other particulate matters, especially clay, organic molecules, and polymers. Hence, full understanding of the movement of them in various environmental zones is strongly demanded. In order to reveal such transport processes of radiocesium in aquatic systems, we have so far developed a code, 3D-Sea-SPEC (3D Sea Simulation for Port and its Environmental Coast).  The code is composed of CFD based simulation solvers using LES scheme and aimed especially for analysis of complex aquatic zones like reservoirs and port areas. In this presentation, we give an overview of 3D-Sea-SPEC and show the technical improvements in realizing the water temperature stratification commonly seen in reservoirs and port areas under strong sun radiation in summer season. Next, we actually apply the improved code to a typical reservoir and a port area around 1F site, and demonstrate characteristic behaviors of the suspended sediment-sorbed radiocesium.

How to cite: Machida, M., Yamada, S., and Kurikami, H.: Characteristic radiocesium transport in temperature-stratified reservoirs and port-areas: Analysis by using a code, 3D-Sea-SPEC, developed for complex aquatic areas, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22277, https://doi.org/10.5194/egusphere-egu2020-22277, 2020.

EGU2020-18812 | Displays | GI2.8

The impact of Ignalina Nuclear Power Plant on Carbon-14 content in Lake Druksiai, Lithuania

Laurynas Butkus, Rūta Barisevičiūtė, Žilvinas Ežerinskis, Justina Šapolaitė, Evaldas Maceika, Andrius Garbaras, Algirdas Pabedinskas, Jonas Mažeika, and Vidmantas Remeikis

Nuclear Power Plants (NPPs) and nuclear fuel reprocessing sites are main producers of anthropogenic radiocarbon. Anthropogenic 14C can be released into the environment in gaseous forms, with liquid effluents or with spent nuclear fuel [1]. During photosynthesis radiocarbon can be easily assimilated into the plants. As a result, carbon-14 can be transported through the food chain and accumulate in a human body. Therefore, radiocarbon is considered a primary source of increased human radiation dose from industrial nuclear activities [2].

Main goal of this research was to evaluate the influence Ignalina NPP on carbon-14 content in the Lake Druksiai. The sediment core was collected from the Lake Druksiai. The ages of sediment layers were estimated using 137Cs and 210Pb dating methods. ABA (acid-base-acid) chemical pretreatment procedure was used to extract humin (HM) and humic acid (HA) fractions from the sediments. Chemically pretreated samples were graphitized with the Automated Graphitization Equipment AGE 3 (IonPlus AG). Carbon-14 measurements in prepared samples were performed using the single stage accelerator mass spectrometer (SSAMS, NEC, USA).

Radiocarbon content was measured in the sediment core which covers all phases of the NPP exploitation (commissioning, operation and decommissioning). These measurements in HM and HA fractions showed that after the start of the operation of the Ignalina NPP in 1983, the 14C concentration in these organic fractions increased by 4 pMC and 3 pMC, respectively. In addition, a sharp increase of radiocarbon content (concentration almost doubled) in HA fraction was observed in the year 1999. Similar increase in 14C activity in fish samples from Lake Druksiai was measured. In HM fraction such drastic changes in radiocarbon concentration were not observed. These results suggest that 14C enriched effluents were released from the Ignalina NPP in 1999.

[1] Z. Ezerinskis et al., Annual Variations of 14C Concentration in the Tree Rings in the Vicinity of Ignalina Nuclear Power Plant, Radiocarbon 60, 1227–1236 (2018).

[2] IAEA, Generic Models for Use in Assessing the Impact of Discharges of Radioactive Substances to the Environment (2001).

How to cite: Butkus, L., Barisevičiūtė, R., Ežerinskis, Ž., Šapolaitė, J., Maceika, E., Garbaras, A., Pabedinskas, A., Mažeika, J., and Remeikis, V.: The impact of Ignalina Nuclear Power Plant on Carbon-14 content in Lake Druksiai, Lithuania, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18812, https://doi.org/10.5194/egusphere-egu2020-18812, 2020.

EGU2020-3175 | Displays | GI2.8

Long range transport of radiocaesium derived from global fallout and the Fukushima accident in the ocean interior of the Pacific Ocean since 1960s through 2017

Michio Aoyama, Yasunori Hamajima, Yayoi Inomata, Hideki Kaeriyama, Yuichiro Kumamoto, Toshiya Nakano, and Eitaro Oka

The world's oceans act as a sink for artificial radionuclides as well as for other anthropogenic pollutants released into the environment. Owing to physical and biogeochemical processes in the ocean, artificial radionuclides in the ocean are redistributed from their initial entry points which depend on the various sources. Long range transport of radiocaesium in the ocean interior were investigated and presented. Radiocaesium were derived from global fallout which occurred mainly late 1950s and early 1960s and the Fukushima accident occurred in 2011. In the ocean interior, main factor is subduction of mode water formation from surface to two mode waters, STMW and CMW. Radiocaesium then stayed long in both STMW and CMW, but relatively first recirculation and southward movement were observed in STMW for decadal time scale.

We establish database for artificial Radionuclides in the marine environment as HAM global 2018, doi: 10.34355/CRiED.U.Tsukuba.00001, and we reconstruct 137Cs activity concentration sections for 1965-1968 and 1970-1973 to understand initial conditions of 137Cs activity concentration in ocean interior just after large atmospheric fallout in early 1960s and 5 years after injection. We also carried out observations at stations between 49 deg. N and 60 deg. S along 165 deg.  E in 2002, 2012 and 2015. After that, we also observed vertical profiles in the western North Pacific Ocean. 

Basic feature of radiocaesium distribution along 165 deg. E section in 1963-1965 was dome shape distribution of which deepest places were around 30-40 deg. N and of which maximum depth were around 600- 800 meter depths. The penetration of 137Cs is found less than 800 m depth, associated with the bowl shape of isopycnals in the midlatitude region. In general, the 137Cs activity concentrations in the subsurface and intermediate water of the mid latitude region of the western North Pacific were higher than those in surface waters of the subtropical and equatorial Pacific. In 2002, we observed two 137Cs activity concentration maxima at 250 m and at 400 to 500 m depth at around 20 deg. N. The 137Cs activity concentration at the core at 400 to 500 m depth in 2002 was around 2 – 3 Bq m-3 and the start of moving in 1963-1965 was 16 Bq m-3 which indicates only one thirds of dilution occurred during about 40 years travel in the ocean interior as CMW. In 2012, we also observed two 134Cs activity concentration maxima at 150 m, 30 deg. N and at 300 m depth at 40N, while we observed a Fukushima derived at 300 m, 30 deg. N with southward movements. Basic feature of 137Cs distribution derived from atmospheric weapons test along 165 deg. E section in 2012 still keep dome shape distribution of which deepest places were around 30-35 deg. N and of which maximum depth were around 400 meters depths, while deepest places were around 20-30 deg. N in 2015. These findings strongly suggest that radiocaesium has been transporting in the ocean interior by subduction of mode waters from subarctic region to subtropical region and tropical region.

How to cite: Aoyama, M., Hamajima, Y., Inomata, Y., Kaeriyama, H., Kumamoto, Y., Nakano, T., and Oka, E.: Long range transport of radiocaesium derived from global fallout and the Fukushima accident in the ocean interior of the Pacific Ocean since 1960s through 2017, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3175, https://doi.org/10.5194/egusphere-egu2020-3175, 2020.

EGU2020-11813 | Displays | GI2.8

Analysis of 60-yr record of surface 137Cs concentrations in the global ocean

Yayoi Inomata and Michio Aoyama

We investigated spatial and temporal variations in 137Cs concentrations in the surface waters of the global ocean for the period from 1957 to 2018. In order to study the distribution of 137Cs concentrations in surface seawater, we divided the global ocean into 37 latitudinal boxes on the basis of known ocean current systems, latitudinal and longitudinal distributions of 137Cs concentrations, the distribution of global fallout, locations of nuclear reprocessing plants, fallout from the Chernobyl accident, and release from Fukushima Nuclear Power Plant accident. Based on the 0.5-y average value of 137Cs concentrations in the surface water in each box, we classified the temporal variations into four types. In the North Pacific Ocean where there was high fallout from atmospheric nuclear weapons tests, the rates of decrease in the 137Cs concentrations changed over the five decades: the rate of decrease from the 1950s to the 1970s was much faster than that after the 1970s, and the 137Cs concentrations were almost constant after the 1990s. Latitudinal differences in 137Cs concentrations in the North Pacific Ocean became small with time. After March 2011, extremely high concentrations (3.26×107 Bq/m3) were observed in the western North Pacific Ocean based on the direct release and atmospheric deposition of FNPP1-derived 137Cs. In the equatorial Pacific and Indian Oceans, the 137Cs concentrations varied within a constant range in the 1970s and 1980s, due to the advection of 137Cs from areas of high global fallout in the mid-latitudes of the North Pacific Ocean. In the eastern South Pacific and Atlantic Oceans (south of 40°S), the concentrations decreased exponentially over the six decades. In the Arctic and North Atlantic Oceans, including marginal seas, 137Cs concentrations were strongly controlled by discharge from nuclear reprocessing plants after the late 1970s. The 137Cs concentrations were rapidly decreased after the early 1980s, and advected into the Arctic Ocean. 
The averaged 137Cs concentrations in each box in the year of 1970 were 1-716 Bq/m3, and those were decreased to 0.2-28 Bq/m3 in the year of 2010. The apparent half-residence times of 137Cs in the surface waters of the global ocean from 1970 to 2010 ranged from 4.2 to 48.1 years for each box. 

(Reference)
Inomata et al. (2009) Analysis of 50-y record of surface 137Cs concentrations in the global ocean using the HAM-global database. Journal of Environmental Monitoring, DOI: 10.1039/b811421h. 

 

How to cite: Inomata, Y. and Aoyama, M.: Analysis of 60-yr record of surface 137Cs concentrations in the global ocean, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11813, https://doi.org/10.5194/egusphere-egu2020-11813, 2020.

EGU2020-12627 | Displays | GI2.8

Comparison of 137Cs activity between an ocean general circulation model and the global database

Daisuke Tsumune, Frank Bryan, Keith Lindsay, Kazuhiro Misumi, Takaki Tsubono, Yayoi Inomata, and Michio Aoyama

We investigate the oceanic dispersion of 137Cs (half-life of 30.1 years) and its impact on the environment. 137Cs has been released into the ocean due to the atmospheric weapons tests, discharge from nuclear reprocessing plants, the Chernobyl accident, and most recently due to Fukushima Daiichi Nuclear Power Plant (1F NPP) accident. 137Cs activities measured for scientific purposes as well as environmental health and safety monitoring have been summarized in a historical database by IAEA. The spatio-temporal density of the observations varies widely, therefore simulation by an ocean general circulation model (OGCM) can be helpful in the interpretation of these observations. Although simulations of 137Cs activity by OGCMs have been carried out previously, the input condition of 137Cs still has large uncertainties due to a lack of observations of global fallout. The horizontal resolution of the previously available estimated global fallout of 137Cs was 10 degree longitude x latitude. We have produced a new estimate of the global fallout of 137Cs with 2.5-degree resolution using the Global Precipitation Climatology Project (GPCP) data, and investigated the impact of the revised input condition on the simulation of distribution of 137Cs in the ocean. In addition, discharges of 137Cs from the reprocessing plants (Sellafield and La Hague) were also considered. We used the Parallel Ocean Program version 2 (POP2) of the Community Earth System Model version 2 (CESM2). The horizontal resolution is 1.125 degree of longitude, and from 0.28 degree to 0.54 degree of latitude. There are 60 vertical levels with a minimum spacing of 10 m near the ocean surface, and increased spacing with depth to a maximum of 250 m. The simulated period was from 1945 to 2010 with the circulation forced by repeating (“Normal Year”) atmospheric conditions. We estimated the global distribution of 137Cs deposition from 1945 to 2010 by using these geographical distribution data, the observed time-series data of annual 137Cs deposition at the MRI from 1958 to 2010, and time-series data of 137Cs deposition from 1945 to 1958 estimated from ice-core data. Simulated 137Cs activities derived from the 2.5-degree deposition data were in good agreement with observations, particularly in the Pacific Ocean. Simulated 137Cs activities were strongly influenced by the discharge of 137Cs from the reprocessing plants. Transport processes were also investigated in the simulated results.

How to cite: Tsumune, D., Bryan, F., Lindsay, K., Misumi, K., Tsubono, T., Inomata, Y., and Aoyama, M.: Comparison of 137Cs activity between an ocean general circulation model and the global database, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12627, https://doi.org/10.5194/egusphere-egu2020-12627, 2020.

EGU2020-4451 | Displays | GI2.8

Transport of the Cs-134 activity derived from Fukushima Dai-ichi Nuclear Power Plant in the North Pacific Ocean

Takaki Tsubono, Kazuhiro Misumi, Daisuke Tsumune, Michio Aoyama, and Katsumi Hirose

We conducted the ensemble simulation of Cs-134 activity in the North Pacific Ocean (NPO) water after the Fukushima Dai-ichi Nuclear Power Plant (1F NPP) by setting four different passive tracers corresponding to the fluxes of the Cs-134 activity; 1. Cs_DD for Cs-134 activity directly discharged from the coast of the 1F NPP (Tsumune et al., 2013), 2. Cs_ADN for the activity derived from the atmospheric deposition (Aoyama et al, 2015) northern from 36°N, 3. Cs_ADKE for that in the Kuroshio Extension area from 32°N or 36°N, 4. Cs_ADS for that southern from 32°N. The totals of the Cs_DD, Cs_ADN, Cs_ADKE and Cs_ADS in the NPO in May 2011 are 5.6, 8.7, 1.0 and 0.6 PBq respectively, suggesting that the impact was dominant northern from 36°N in the NPO. The sum of four tracers showed comparable to the Cs-134 activity from all the fluxes in previous study with the correlation coefficient of 0.99 and the RMS of 5 Bq m$^{-3}$ in 2011 and 0.99 and 0.1 Bq m$^{-3}$ in 2012, except for the area of Japanese coast near the 1F NPP in which the rapid increase in the direct discharge flux produced the different negative values due to the dispersive error of the difference scheme. Since the Cs-134 activity diminishes in time due to the short half life of about 2 years, the abundance ratio was calculated for the investment of the meridional and vertical transport. The abundance ratio of the whole Cs-134 activities showed that although almost all the Cs-134 activity existed in the surface layer above 200m depth after the accident, the ratio in the intermediate layer from 200m to 600m depth increased and exceeded 50 percent since 2017. Moreover the ratio in the intermediate layer southern from 32°N exceeded the 25 percent since 2017, suggesting that more than 25 percent of the Cs-134 activity in the surface layer northern to the 36°N in early period after the accident were transported to the southern and deep in 2017. While the abundance ratio of Cs_DD and Cs_ADN in the intermediate layer showed an increase like a logarithmic function shape, the ratio of the Cs_DD, 60 percent, was larger than that of the Cs_ADN, 50 percent, in 2021. Moreover, the abundance ratio in 2011 showed the 70 percent of Cs_DD and Cs_ADN existed in the intermediate layer southern to the 32 °N, suggesting a large amount of both the Cs_DD and Cs_ADN were transported southern and deep in 2021.

How to cite: Tsubono, T., Misumi, K., Tsumune, D., Aoyama, M., and Hirose, K.: Transport of the Cs-134 activity derived from Fukushima Dai-ichi Nuclear Power Plant in the North Pacific Ocean, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4451, https://doi.org/10.5194/egusphere-egu2020-4451, 2020.

EGU2020-21319 | Displays | GI2.8

Analysis of temporal variations of Cs-137 discharge inventory from the port of Fukushima Daiichi Nuclear Power Plant over 9 years after the accident

Susumu Yamada, Masahiko Machida, Ayako Iwata, Shigeyoshi Otosaka, Takuya Kobayashi, Masahisa Watanabe, Hideyuki Funasaka, and Takami Morita

Just after Fukushima Daiichi Nuclear Power Plant (1F) accident occurred in March 2011, the direct discharges of highly-contaminated water from reactor Unit 2 and 3 into the 1F port followed. After the suppressions of the direct discharges, Kanda (Biogeosci. 10, 6107–6113, 2013) suggested that relatively small amounts of run-off of a radionuclide (Cs-137) from 1F port into Fukushima coastal region has continued based on his estimation method. However, Kanda’s estimation period was limited up to September 2012. Therefore, we expand the estimation period of the discharged inventory up to very recently, March 2020 with significant accuracy improvements by the present authors. As a result, we find that totally, in the period over 9 years, the discharged inventory has gradually diminished together with various characteristic fluctuations. In this presentation, we analyze the observed diminishing trends with temporal fluctuations and discuss their relationships with various suppression measures and constructions toward decommissioning of 1F. Furthermore, we estimate the annual discharged amount of Cs-137 and evaluate its impacts on the coastal area in terms of seawater concentrations.

How to cite: Yamada, S., Machida, M., Iwata, A., Otosaka, S., Kobayashi, T., Watanabe, M., Funasaka, H., and Morita, T.: Analysis of temporal variations of Cs-137 discharge inventory from the port of Fukushima Daiichi Nuclear Power Plant over 9 years after the accident, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21319, https://doi.org/10.5194/egusphere-egu2020-21319, 2020.

EGU2020-6987 | Displays | GI2.8

Discovery of radiocesium-bearing microparticles from ocean samples emitted from the Fukushima Daiichi Nuclear Power Plant accident

Hikaru Miura, Takashi Ishimaru, Yukari Ito, Jota Kanda, Atsushi Kubo, Shigeyoshi Otosaka, Yuichi Kurihara, Daisuke Tsumune, and Yoshio Takahashi

Introduction: A large amount of radioactive Cs was emitted into the environment by the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. Adachi et al. (2013) first reported radiocesium-bearing microparticles (CsMPs) from aerosol filters. Subsequent researches showed that the CsMP is SiO2 glass with Cs, Cl, K, Fe, and Zn mainly contained in the particle. Diameter of CsMP is ~1-10 μm and 137Cs radioactivity is ~0.5 to 102 Bq. It has been suggested that the CsMP was mainly emitted from Unit 2 or Unit 3 of FDNPP based on the 134Cs/137Cs activity ratio in the samples. Miura et al. (2018) reported CsMPs from the suspended particles in river water and their effect on Kd value, which suggested CsMPs may exist in the ocean transported through rivers. Kubo et al. (2018) and Ikenoue et al. (2018) reported hot spots in the ocean samples by autoradiography but they did not separate CsMPs from these spots. In this presentation, we first report CsMPs separated from marine suspended particles, sinking particles, and sediments in coastal area of Fukushima and compare them with CsMPs from the terrestrial samples.

Method: We collected suspended particles (2011, 2013, 2015), sinking particles (2014), sediment cores (2011) from coastal area of Fukushima. By a wet separation method (Miura et al., 2018), we separated CsMPs from these samples. After measurement of radioactivity with a high-purity germanium semiconductor detector, scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) analyses were performed for separated CsMPs. Using autoradiography, we calculated 137Cs activity of unseparated hot spots over 0.1 Bq, which may be CsMPs.

Results and discussion: We separated 5 CsMPs from marine samples. The results of SEM-EDS analyses showed that these CsMPs have almost similar characteristics to the reported CsMPs because they mainly consist of Si, Cs, Fe, and Zn.  Their 134Cs/137Cs showed that the CsMPs were from Unit 2 or 3 of FDNPP. 137Cs radioactivity per volume is also similar to reported CsMPs from Unit 2 or 3. In this presentation, we will show the effect of CsMPs on Kd values. CsMPs in the ocean samples will make apparent Kd values be higher than intrinsic Kd values related to the adsorption-desorption reaction to the clay minerals, which may explain the large variation of Cs concentration in marine samples.

How to cite: Miura, H., Ishimaru, T., Ito, Y., Kanda, J., Kubo, A., Otosaka, S., Kurihara, Y., Tsumune, D., and Takahashi, Y.: Discovery of radiocesium-bearing microparticles from ocean samples emitted from the Fukushima Daiichi Nuclear Power Plant accident , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6987, https://doi.org/10.5194/egusphere-egu2020-6987, 2020.

GI3.1 – Open session on planetary and space instrumentation

EGU2020-14126 | Displays | GI3.1

Validation and characterisation of the Sweeping Langmuir Probe (SLP) instrument for the PICASSO mission

Sylvain Ranvier, Michel Anciaux, Jean-Pierre Lebreton, and Johan De Keyser

The Sweeping Langmuir Probe (SLP) instrument, that uses a novel measurement technique to take into account spacecraft charging effects, has been developed at the Royal Belgian Institute for Space Aeronomy. SLP will fly on board the ESA scientific in-orbit demonstrator PICASSO together with the hyper-spectral imager VISION. PICASSO, a triple unit CubeSat, will be launched in March 2020. The goal of the mission is to prove the feasibility of performing true science (with limited extent) with a nano-satellite and demonstrate the very low cost / science ratio with respect to big missions. SLP will allow a global monitoring of the ionosphere with a maximum spatial resolution of the order of 150 m.  The main goals are to study the ionosphere-plasmasphere coupling, the subauroral ionosphere and corresponding magnetospheric features together with auroral structures and polar caps, by combining SLP data with other complementary data sources (space- or ground-based instruments). SLP can measure plasma density from 1e8/m³ up to 1e13/m³ and electron temperature up to 15 000 K.

We will present the main results from the validation tests performed in the plasma chamber at ESTEC together with comparisons with particle-in-cell (PIC) simulations performed with SPIS (Spacecraft Plasma Interaction System).

How to cite: Ranvier, S., Anciaux, M., Lebreton, J.-P., and De Keyser, J.: Validation and characterisation of the Sweeping Langmuir Probe (SLP) instrument for the PICASSO mission, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14126, https://doi.org/10.5194/egusphere-egu2020-14126, 2020.

EGU2020-4409 | Displays | GI3.1

Thermal behaviour of ram-facing instruments during deep dives into a planetary atmosphere: The case of Daedalus/CWS

Johan De Keyser, Marius Echim, Sylvain Ranvier, Thomas Chambon, Björn Ordoubadian, and Norbert Lemke

Spacecraft that aim to study the atmosphere of a planetary object through in situ sampling face the problem of strong atmospheric drag. In order not to compromise mission lifetime, the orbit can be designed so that repeated deep dives into the upper atmosphere are performed to sample atmospheric density, pressure, and composition down to relatively low altitudes. During such deep dives, ram-facing instruments, such as ion and neutral wind instruments, in particular are exposed to a severe heating flux.

The present contribution focuses on the particular case of the neutral Cross-Wind Sensor (CWS) under study for the Daedalus Earth Explorer 10 mission led by ESA, which will sample the Earth’s upper atmosphere during its perigee passes at an altitude currently planned to be in the 110 to 140 km range. Thermal simulations are presented that show the transient heat loads on the CWS instrument. It is shown that, with an appropriate materials choice, these heat loads can be dealt with in a satisfactory manner.

How to cite: De Keyser, J., Echim, M., Ranvier, S., Chambon, T., Ordoubadian, B., and Lemke, N.: Thermal behaviour of ram-facing instruments during deep dives into a planetary atmosphere: The case of Daedalus/CWS, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4409, https://doi.org/10.5194/egusphere-egu2020-4409, 2020.

EGU2020-2955 | Displays | GI3.1

Development of the NIM Mass spectrometer for Exploration of Jupiter’s Icy Moons Exospheres

Martina Föhn, Marek Tulej, André Galli, Audrey Helena Vorburger, Davide Lasi, Peter Wurz, Pontus Brandt, and Stas Barabash

Investigation of habitable environments is one of the main objectives in upcoming space missions. The JUICE mission will investigate Jupiter’s environment in the solar system and its icy moons Ganymede, Callisto and Europa as examples for potentially habitable worlds around a gas giant. The Particle Environment Package (PEP) on the JUICE satellite will investigate Jupiter’s icy moons and their environment. As part of PEP, the Neutral gas and Ion Mass spectrometer (NIM) will measure the chemical composition of the exospheres of the icy moons. These measurements give information about the surface composition of the moons and will set constraints on their formation processes.

NIM is a Time of Flight mass spectrometer with two entrances for neutral particles and ions. The gas enters the instrument from spacecraft ram direction. With the open source neutral particles and ions enter the ionisation region directly. With the closed source neutral particles get thermalized using an antechamber before entering the ion source. Particles entering with higher velocity are therefore easier to detect through the antechamber.

Initial performance tests with the NIM Protoflight Model (PFM) were done. The storage capability of the ion source was tested, the functionality of the antechamber was verified and we measured masses up to 642 u to demonstrate the high-mass performance of NIM. Furthermore, different subunits of the NIM instrument were successfully tested, such as the redesigned ion source and flight electronics connected with the NIM sensor head.

How to cite: Föhn, M., Tulej, M., Galli, A., Vorburger, A. H., Lasi, D., Wurz, P., Brandt, P., and Barabash, S.: Development of the NIM Mass spectrometer for Exploration of Jupiter’s Icy Moons Exospheres, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2955, https://doi.org/10.5194/egusphere-egu2020-2955, 2020.

EGU2020-3177 | Displays | GI3.1

Compact High Resolution QIT-Mass Spectrometers for Lunar and Planetary Applications

Frank Maiwald, Jurij Simcic, Dragan Nikolic, Anton Belousov, and Stojan Madzunkov

The JPL Mass Spectrometer Team develops components and instruments based on a Paul quadrupole ion trap mass spectrometer (QIT-MS) for Earth and space applications. Over the past 20 years, the team has miniaturized the QIT-MS and verified its performance successfully for the International Space Station. The technology was demonstrated with the recent delivery of the first Spacecraft Atmosphere Monitor (S.A.M.) to the International Space Station (ISS).

The next step is to build a QIT-MS intendent to investigate the lunar exosphere via a funded ROSES 2019, DALI/NASA proposal over the next three years.

The QIT-MS will be the first in-situ lunar mass spectrometer capable of identifying and quantifying exosphere species (ex. H, H2, 3He, 4He, Ne, N2, O2, Ar, CH4, CO, CO2, Kr, Xe, OH, H2O) with abundance greater than 10 molecules/cm3 [1]. The combination of low mass (7.5 kg), low power (max. 30W with heater bulb on), high sensitivity (0.003 counts/cm3/sec), and ultrahigh precision (1.7 x 10-10 Torr, Kr measured continuously for 7 hours yielded a 0.6 ‰ precision on the 86Kr/84Kr ratio) will provide an unpreceded inside of the scientific processes in the lunar exosphere.

Other implementation approaches will be discussed, which entail the development of different frontends to expand applications for dense atmospheres (ex. Venus) or liquids (ex. ocean worlds). Most of these developments can be used to determine contaminants in the air, water, or volatile in solids.

[1] G. Avice, A. Belousov, K. A. Farley, S. M. Madzunkov, J. Simcic, D. Nikolic, M. R. Darrach and C. Sotin, “High-precision measurements of krypton and xenon isotopes with a new static-mode quadrupole ion trap mass spectrometer,” JAAS, Vol 34, January 2019

 

Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109

 

How to cite: Maiwald, F., Simcic, J., Nikolic, D., Belousov, A., and Madzunkov, S.: Compact High Resolution QIT-Mass Spectrometers for Lunar and Planetary Applications, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3177, https://doi.org/10.5194/egusphere-egu2020-3177, 2020.

EGU2020-8870 | Displays | GI3.1 | Highlight

Instrumentation for Nuclear Planetology: Present and Future

Maxim Mokrousov, Igor Mitrofanov, Alexander Kozyrev, Maxim Litvak, Alexey Malakhov, Anton Sanin, Vladislav Tretyakov, Dmitry Golovin, and Artem Anikin

The method of remote neutron and gamma spectrometry of bodies in the solar system (the Moon, Mars, and Mercury) has been used for several decades to estimate the nuclear composition of these objects and the hydrogen abundance in their subsurface layers. It is known that many solid planets of Solar system with thin atmospheres, its moons, small bodies and even comets due to bombardment by heavy nucleus of Galactic Cosmic Rays (GRS) produce neutron albedo and characteristic gamma lines. Detection of escaping gammas and neutrons (remote sensing from an orbit or in situ) bringing an information about elemental composition of the subsurface and hydrogen-containing elements (as deep as tens of centimeters). Currently we can classify all nuclear planetology instruments by the field of view (uncollimated and collimated) and by type of soil irradiation (passive – using GRS, and active – using pulsing neutron generator onboard), each of those methods has pros and cons and all of them will be presented. Also, future nuclear planetology instruments and method in design will be presented.

How to cite: Mokrousov, M., Mitrofanov, I., Kozyrev, A., Litvak, M., Malakhov, A., Sanin, A., Tretyakov, V., Golovin, D., and Anikin, A.: Instrumentation for Nuclear Planetology: Present and Future, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8870, https://doi.org/10.5194/egusphere-egu2020-8870, 2020.

EGU2020-10565 | Displays | GI3.1

SP4GATEWAY: a Space Plasma Physics Payload Package conceptual design for the Deep Space Gateway Lunar Orbital Platform

Iannis Dandouras, Pierre Devoto, Johan De Keyser, Yoshifumi Futaana, Ruth Bamford, Graziella Branduardi-Raymont, Dragos Constantinescu, Jean-Yves Chaufray, Jonathan Eastwood, Marius Echim, Benjamin Grison, David Hercik, Anna Milillo, Rumi Nakamura, Lubomír Přech, Elias Roussos, Štěpán Štverák, André Laurens, Josef Winter, and Matt G. G. T. Taylor and the SP4GATEWAY Team

The Deep Space Gateway is a crewed platform that will be assembled and operated in the vicinity of the Moon by ESA and its international partners in the early 2020s and will offer new opportunities for fundamental and applied scientific research. The Moon is a unique location to study the deep space plasma environment, due to the absence of a substantial intrinsic magnetic field and the direct exposure to the solar wind, galactic cosmic rays (GCRs) and solar energetic particles (SEPs). However, 5-6 days each orbit, the Moon crosses the tail of the terrestrial magnetosphere facilitating the in-situ study of the terrestrial magnetotail plasma environment as well as atmospheric escape from the ionosphere. When back outside of the magnetosphere, a variety of these and other phenomena, e.g. those driving solar-terrestrial relationships, can be investigated through remote sensing using a variety of imaging techniques. Most importantly, the lunar environment offers a unique opportunity to study the interaction of the solar wind and the magnetosphere with the lunar surface and the lunar surface-bounded exosphere. In preparation of the scientific payload of the Deep Space Gateway, we have undertaken a conceptual design study for a Space Plasma Physics Payload Package onboard the Gateway (SP4GATEWAY). The main goal is first to provide a science rationale for hosting space plasma physics instrumentation on the Gateway and to translate that into a set of technical requirements. A conceptual payload design, that identifies a strawman payload and is compatible with the technical requirements, is then put forward. The final outcome of this project, which is undertaken following an ESA AO, is an implementation plan for this space plasma physics payload package.

How to cite: Dandouras, I., Devoto, P., De Keyser, J., Futaana, Y., Bamford, R., Branduardi-Raymont, G., Constantinescu, D., Chaufray, J.-Y., Eastwood, J., Echim, M., Grison, B., Hercik, D., Milillo, A., Nakamura, R., Přech, L., Roussos, E., Štverák, Š., Laurens, A., Winter, J., and Taylor, M. G. G. T. and the SP4GATEWAY Team: SP4GATEWAY: a Space Plasma Physics Payload Package conceptual design for the Deep Space Gateway Lunar Orbital Platform, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10565, https://doi.org/10.5194/egusphere-egu2020-10565, 2020.

EGU2020-22255 * | Displays | GI3.1 | Highlight

First Farm for Lunar Polar Base

James Burke

Food production will of course be critical for lunar living. The leaders will be growing plants first in small quantities for research to see how they perform in the lunar environment (radiation, partial gravity), then to supplement key nutrients the existing lunar diet might lack over time (likely with pick and eat type crops such as leafy vegetables, fruiting plants like peppers and micro greens) and finally to replace calories and associated up-mass at some future time based on the expansion of human presence and activity (staple crops such as potatoes, wheat etc.). Here we discuss a start-up proof-of-concept farm where tests can be carried out to validate plans for a later, full-scale farm. The concept will take advantage of previous work on Earth and in low earth orbit including experiments aboard the International Space Station, and will be designed for variation of all relevant parameters. Examples of variables will be the fractional duration and intensity of sunlight or artificial light sent to trays of growing crops from a primary mirror tracking the Sun around the horizon and the organization of planting, fertilizing and harvesting of products. It’s expected that LED lighting will provide the light source in a majority of concept applications. LED’s allow us to tailor specific light recipies optimal for the plant types we select. This is how things are done today in Controlled Environment Agriculture (CEA) on Earth. The organization and sequencing of planting operations is important as is water and nutrient delivery, harvesting and waste product recycling. The role automation, robotics and food safety are very important since we are likely not going to be sending farmers anytime soon and crew time for lunar exploration will be the priority. Ultimately we must plan to include the farm as part of a bioregenerative life support. The crops will be partly spread out on the surface and partly arranged in a sloping list, covered by a transparent cover equipped with provisions for cleaning. Among the concepts to be tested will be the delivery of water from a source in a lunar mine.

 

 

 

 

 

How to cite: Burke, J.: First Farm for Lunar Polar Base, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22255, https://doi.org/10.5194/egusphere-egu2020-22255, 2020.

EGU2020-2090 | Displays | GI3.1

Pre-flight Calibration and validation test of CMM-1 Fluxgate Magnetometer MAG-O

Xiaowen Hu, Kai Liu, Xin Li, Zonghao Pan, Yiren Li, Xinjun Hao, and Tielong Zhang

As one of the objectives for China’s First Mars Exploration Mission (CMM-1), the magnetic field in Mars’ near space will be measured by the Magnetometer onboard of the Orbiter (MAG-O), which consists of two fluxgate sensors and one electronic box. We conducted pre-flight calibration test to determine the temperature dependent offset and the correction matrix, which composed of sensitivities and non-orthogonality parameters. Two sets of ground validation experiments were also executed under limited condition to confirm the consistency and mutual interference of the two sensors, respectively. The results show that MAG-O meets the requirements of CMM-1 mission. This paper will introduce the procedure and results of pre-flight calibration and validation test.

How to cite: Hu, X., Liu, K., Li, X., Pan, Z., Li, Y., Hao, X., and Zhang, T.: Pre-flight Calibration and validation test of CMM-1 Fluxgate Magnetometer MAG-O, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2090, https://doi.org/10.5194/egusphere-egu2020-2090, 2020.

EGU2020-6461 | Displays | GI3.1

A 1 eV - 1000 eV ion beam system designed for the calibration of low-energy ion mass spectrometers

Yiren Li, Bin Miao, Xinjun Hao, Tielong Zhang, and Yuming Wang

For the calibration of space plasma analyzers, in particular low-energy ion mass spectrometers, a low energy ion beam system was developed. The positive ion beam is produced by a hot-cathode penning source and modified by a series of electrostatic lenses. And a 75 mm diameter 2-D imaging system and a Faraday cup mounted on movable arms are used for ion beam diagnostics. With protons as primary species, the system provides an ion beam in the energy range of 1 eV - 1000 eV with a large area ( ~ 50 cm2), highly parallel ( ± 0.5°), and spatially uniform ( ± 5%).

How to cite: Li, Y., Miao, B., Hao, X., Zhang, T., and Wang, Y.: A 1 eV - 1000 eV ion beam system designed for the calibration of low-energy ion mass spectrometers, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6461, https://doi.org/10.5194/egusphere-egu2020-6461, 2020.

EGU2020-7866 | Displays | GI3.1

Influence of Alfvénic characteristics on calibration of satellite magnetometer

Zonghao Pan, Guoqiang Wang, LiFei Meng, and Tielong Zhang

The zero offset of the fluxgate magnetometer in satellite orbit will be changed due to several factors. For this reason, the Davis-Smith method is proposed to calculate the zero compensation of the magnetometer based on the feature that the shear Alfvén waves do not change the total magnetic field strength. In fact, there is no pure Alfvén waves in the interplanetary space. In this paper, numerical simulation is used to analyze the influence of the amplitude, period and phase of the Alfvén waves and the time length of the data window on the zero offset of the magnetometer calculated by the Davis-Smith method in the presence of weak compressional waves. We find that Alfvén waves can produce a non-negligible error in the calculation of zero compensation only when its period is the same as the period of the compressional wave. The greater the amplitude of Alfvén waves, the smaller the error of the zero offset. The error of the zero offset is also affected by the initial phase of the Alfvén wave. In addition, the error of the zero offset tends to decrease to its true value for the longer the data window length.

How to cite: Pan, Z., Wang, G., Meng, L., and Zhang, T.: Influence of Alfvénic characteristics on calibration of satellite magnetometer, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7866, https://doi.org/10.5194/egusphere-egu2020-7866, 2020.

EGU2020-9298 | Displays | GI3.1

Design considerations for a dust collector on mesospheric rocket

Henriette Trollvik, Ingrid Mann, Ove Havnes, Sveinung Olsen, and Yngve Eilertsen

Meteors ablation is a source of dust particles in the upper atmosphere. The remnants of meteor ablation that prevail in the mesosphere condense to nm-sized particles, denoted as Meteoric Smoke Particles (MSPs). Theory suggest that MSPs act as condensation nuclei for ice particles in the summer mesosphere, which form during summer months around the mesopause at high and mid latitudes. They are related to mesospheric phenomena such as the Noctilucent Clouds, Polar Mesospheric Summer and Winter Echoes (PMSE/PMWE). However, due to their altitude location, the only means of in situ measurement is with rocket experiments. There have been several attempts to collect these MSP particles with probes on rockets over the years, but no conclusive results have been reported so far.

UiT have proposed a new sample collector, the MEteoric Smoke Sampler (MESS). We report on the progress of the work that has focused on the design of the detector and simulation of the entry and impact of dust onto the detector. The focus of the planned measurements is on collecting ice particles, since the airflow affect them less than smaller MSPs. Estimations of the collection surface properties and impact energy are presented. An estimate of the expected mass in the traversed volume of one collecting plate, diameter of 3 mm diameter over 1 km, suggest that the volume contains ~1e8 particles. This corresponds to a mass of 7e16 amu. These estimates are made assuming spherical particles with average density 2.8 g per m3 and radius 1 nm, and an MSP density of 1e10 per m3. 

How to cite: Trollvik, H., Mann, I., Havnes, O., Olsen, S., and Eilertsen, Y.: Design considerations for a dust collector on mesospheric rocket, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9298, https://doi.org/10.5194/egusphere-egu2020-9298, 2020.

The Jovian plasma Dynamics and Composition analyzer (JDC), which is part of the Particle Environment Package (PEP) on board of the JUICE spacecraft, uses high voltages up to 5kV, during operations. These high voltages are used in the ion-optical part of the instrument, where the strongest electrical fields are encountered. Preventing internal high voltage discharges in this region is a key design driver. For this reason, a design rule of keeping the field strength <3kV/mm is applied. However, the dielectric strength of a vacuum gap has a pronounced minimum much below the 3kV/mm design rule at the Paschen minimum at about 10-2 to 1 mbar. To successfully operate using the <3kV/mm design rule, the sensor needs proper venting of its inner volume to get the internal pressure significantly below the Paschen minimum pressure.

Below the Paschen minimum pressure the gas flow in the instrument is a non-collisional molecular flow. The time spent to further reduce pressure inside of the instrument when the instrument is exposed to vacuum (e.g. in space or in a test facility) depends on the internal outgassing source strength, the temperature and the geometric shape of the outgassing path.

We determine the time constants of the pressure reduction in molecular flow regime by placing micro pirani pressure sensors inside critical volumes of real instruments.

We compare the outgassing performance of the Miniature Ion Precipitation Analyzer (MIPA) on Bepi Colombo with the JDC sensor. Measurements showed too long outgassing time constants for JDC in order to be able to operate the instrument during the very time constraint on-ground test campaign where only approximately 3 days are available to reach a save vacuum of <10-5 mbar inside of the instrument. We present the implemented solution to improve outgassing performance of JDC and show it is sufficient for the on-ground test campaign.

How to cite: Wittmann, P., Wieser, M., Trost, F., and Barabash, S.: Pressure evolution inside the high voltage modules of plasma instrumentation when exposed to vacuum during ground test campaigns or after launch to space, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19066, https://doi.org/10.5194/egusphere-egu2020-19066, 2020.

EGU2020-19282 | Displays | GI3.1

Calibration Test for Low Energy Ion Spectrometer onboard of Geostationary Satellites

Kai Liu, Yiren Li, and Xin Li

Detections for space environment are crucial for monitoring the safety of satellites, while the parameters of space plasma are fundamental. Thus, we developed a spectrometer onboard of geostationary satellites, and it can measure the low energy ion's 3-D energy spectrum with a single sensor. To ensure the performance of the instrument, environmental tests, such as impulse test, vibration test and thermal test, were proceeded. Furthermore, a fully calibration test has been carried out to obtain all the scaling parameters. In this paper, the facilities and processes of the calibration test will be illustrated in detail, and the test's results indicate that our spectrometer will function well in the geostationary orbit.

How to cite: Liu, K., Li, Y., and Li, X.: Calibration Test for Low Energy Ion Spectrometer onboard of Geostationary Satellites, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19282, https://doi.org/10.5194/egusphere-egu2020-19282, 2020.

EGU2020-21172 | Displays | GI3.1

The Search-Coil Magnetometer onboard the ESA JUICE mission

Alessandro Retinò and the JUICE SCM Team

The JUpiter ICy moons Explorer (JUICE) mission is the first large-class (L1) mission in ESA Cosmic Vision. JUICE is planned for launch in 2022 with arrival at Jupiter in 2029 and will spend at least four years making detailed observations of Jupiter’s magnetosphere and of three of its largest moons (Ganymede, Callisto and Europa). The Radio and Plasma Wave Investigation (RPWI) consortium will carry the most advanced set of electric and magnetic fields sensors ever flown in Jupiter’s magnetosphere, which will allow to characterize the radio emission and plasma wave environment of Jupiter and its icy moons. Here we present the scientific objectives and the technical features of the Search Coil Magnetometer (SCM) of RPWI. SCM will provide for the first time high-quality three-dimensional measurements of magnetic field fluctuations’ vector in the frequency range 0.1 Hz – 20 kHz within Jupiter’s magnetosphere. High sensitivity (~ 4 fT / √Hz  at 4 kHz) will be assured by combining an optimized (20 cm long) magnetic transducer with a low-noise (4 nV / √Hz  ) ASICs pre-amplifier for the front-end electronics. Perturbations by the spacecraft are strongly reduced by accommodating SCM more at ~ 10 m away from the spacecraft on the JUICE magnetometer boom. The combination of high sensitivity and high cleanliness of SCM measurements will allow unpreceded studies of waves and turbulence down to kinetic scales, in particular in key regions such as the magnetopause, the auroral region and the magnetotail current sheet of Ganymede’s magnetosphere. This will lead to important advances in understanding wave-particle interaction and particle energization mechanisms in Jupiter’s magnetosphere.

How to cite: Retinò, A. and the JUICE SCM Team: The Search-Coil Magnetometer onboard the ESA JUICE mission, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21172, https://doi.org/10.5194/egusphere-egu2020-21172, 2020.

EGU2020-10788 | Displays | GI3.1

Lifetime of Channel Electron Multipliers dedicated to Plasma Instruments for Solar Orbiter and JUICE ESA missions

Andrey Fedorov, Rituparna Baruah, and Jean Rubiella Romeo

Both Solar Orbiter and Jupiter Icy moon Explorer (JUICE) are long-life ESA missions, which should work in extremely difficult space environment. A very high thermal load up to 13 Solar constants will affect Solar Orbiter, and JUICE will experience a high penetration radiation influence in the Jupiter magnetosphere. The plasma packages of these missions, dedicated mostly for detection of low energy (between 1eV and 50 keV) ions and electrons shall accept a very high dynamic range of the incident charged particle flow. All these circumstances motivate us to use the Channel Electron
Multiplier (CEM) as detectors in both missions. CEMs are a conventional low energy charged particle and X-ray detectors that have been used fore many early space missions. Later, they were forced out by Micro-Channel Plates (MCP), which
allow to provide an image of the particle distribution. But for such challenge missions as Solar Orbiter and JUICE we have to come back to CEMs because they 1) less sensible to the penetrating radiation 2) have much wide dynamical
range, 3) have much longer lifetime than MCPs. 
The detector lifetime is, actually, the maximum particles number accumulated by detector until its efficiency becomes too low. And this detector feature is critical for Solar Orbiter and JUICE missions.
To check the lifetime of CEMs, for different thermal conditions also, we have made a dedicated experimental setup. We irradiated several CEM samples by a strong electron flux, continuously measuring the CEM gain and keeping 80°C on
the sample. The final total number of events, detected by each CEM was equivalent to two Solar Orbiter nominal mission duration.
The detailed analysis of the experimental data show that the visible degradation of CEMs gain is a function of the vacuum level in the vicinity of the CEM and its outgassing efficiency. If we normalize the CEM gain to the vacuum, expected in the flight, we will see that the pure, completely outgassed CEM can accumulate ten Coulombs of charge without any gain degradation. But in the beginning of the flight, we have to expect very fast gain degradation because of the CEM self-cleaning.

How to cite: Fedorov, A., Baruah, R., and Rubiella Romeo, J.: Lifetime of Channel Electron Multipliers dedicated to Plasma Instruments for Solar Orbiter and JUICE ESA missions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10788, https://doi.org/10.5194/egusphere-egu2020-10788, 2020.

EGU2020-20425 | Displays | GI3.1

A customizable wide field-of-view multiband imager for lunar atmospheric Studies

Supriya Chakrabarti, Sunip Mukherjee, Timothy Cook, and Jeffrey Baumgardner

Ground based observations have indicated that at times the lunar Sodium atmosphere extends beyond the Earth. However, to date no experiment has been conducted to perform an extended duration, in-situ observation of the lunar atmosphere.  We have designed a small (10 × 10 × 10 cmand a mass of 1.3 Kg), multi-band imager that operates in the CCD-band (approximately, 450 – 900 nm). The instrument is easily tailored to meet a specific application by selecting the appropriate combination of interference filters. If such an instrument is placed on a lunar orbiting platform, it will generate a long-term database to study the morphology of the lunar atmosphere or surface features observable in this band.

The instrument has an angular resolution of 0.1and a field of view of 35× 25. This large field of view is shared by a mosaic of interference filters chosen for a specific application. The instrument uses a custom-designed computer program for automatic exposure control and communicates using standard serial and ethernet protocols.

This design has been validated using commercial off-the-shelf components for sodium and potassium resonance emissions at 589 nm and 770 nm, respectively.

How to cite: Chakrabarti, S., Mukherjee, S., Cook, T., and Baumgardner, J.: A customizable wide field-of-view multiband imager for lunar atmospheric Studies, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20425, https://doi.org/10.5194/egusphere-egu2020-20425, 2020.

EGU2020-9593 | Displays | GI3.1

Can we use graphene as a conversion surface for a neutral particle detector?

Alexander Grigoriev, Andrei Fedorov, and Nicolas André

An important technique of modern space plasma diagnostics is a detection and imaging of low energy (below 10 keV) energetic neutral atoms (ENA). Any space mission devoted to study of the planetary plasma environments, planetary magnetospheres and heliosphere boundaries, needs a low energy ENA imaging sensor in its payload list. A common approach to the ENA detection/imaging is to make energetic neutral atoms glance a high quality conductive surface and either produce a secondary electron, or produce a positive or negative reflection ion. In the first case we can collect and detect the yielded secondary electron and generate a start signal. The reflected neutral atom can be directed to another surface with a high secondary electron yield. Thus we can measure a time-of-flight of the reflected particle to get its velocity. In the second case we can analyze the reflected ion in an electrostatic analyzer to get the particle energy.

Many types of conversion surfaces have been investigated over last decades in order to optimize an ENA sensor properties. We investigated properties of a thin layer of graphene applied to a silicon wafer surface. The experimental setup consisted of a secondary electron detector, neutral/ions separator and a high resolution particle imager. We used an incident He beam with energy of 200 eV - 3000 eV. We obtained a secondary electron emission, particle reflection efficiency, scattering properties, and a positive ion production rate as a function of the incident beam energy and the grazing angle. The experiment results show that 1) Graphene is a good source of secondary electrons even for low energy incident particles; 2) ENA scatter from the graphene surface similar to other surface types; 3) Graphene does not convert incident ENA to positive ions, especially for high grazing angles.

How to cite: Grigoriev, A., Fedorov, A., and André, N.: Can we use graphene as a conversion surface for a neutral particle detector?, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9593, https://doi.org/10.5194/egusphere-egu2020-9593, 2020.

GI3.2 – Open session on experimental and modelling techniques for the exploration and sustainable utilization of the Moon

EGU2020-11912 | Displays | GI3.2

Contribution of Gravity to Lunar Science, Exploration and Resource Assessment

Maria T. Zuber and David E. Smith

The recent development of high-resolution models of the lunar gravity field based on data from the NASA GRAIL mission have been instrumental in gaining knowledge about the structure of the Moon, and particularly, of the upper crust. Beneath the outer layer GRAIL data reveal evidence of massive ancient dikes and past processes that no longer have any surficial expression due to heavy bombardment during the Moon’s post-accretional epoch that pulverized the shallow crust. The gravity field of this outer crust, with lower density and higher porosity than expected, also reveals anomalies that indicate the presence of regions of even lower density possibly indicating the existence of lava tubes, as well as regions of higher density where mass anomalies could conceivably indicate locations of resources. Lava tubes, long suspected of existing beneath the maria, are places protected from particle and EM radiation and therefore potential locations for safe location of humans.  Gravity anomaly regions are thus prime locations for exploration studies that could help sustain a human presence. The use of high-resolution  gravity in lunar exploration, as well as science, is a tool for survivability for human expeditions.

How to cite: Zuber, M. T. and Smith, D. E.: Contribution of Gravity to Lunar Science, Exploration and Resource Assessment, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11912, https://doi.org/10.5194/egusphere-egu2020-11912, 2020.

EGU2020-11285 | Displays | GI3.2

Mini-RF Observations of Lunar Polar Craters and Implications for Ice Distribution

Lauren Jozwiak and G. Wes Patterson and the Mini-RF Science Team

The possibility that water ice could be present in lunar polar craters has long been postulated.  More recently, measurements from instruments on a number of spacecraft have all pointed to the presence of water at the lunar poles; although whether that water exists as surficial frost or as extensive, competent ice deposits remains strongly debated. Water ice can exhibit a strong response at radar wavelengths in the form of a Coherent Backscatter Opposition Effect (CBOE) and the circular polarization ratio (CPR) of the returned data can be a useful indicator of such a response—i.e., measured CPRs for icy materials typically exceed unity. Mini-RF is currently operating as part of the Lunar Reconnaissance Orbiter (LRO) Cornerstone Extended Mission to address driving questions related to the form/abundance of water on the Moon and its vertical distribution. Using a combination of monostatic and bistatic observations of the lunar poles, we investigate the radar response of lunar polar craters. Continued analysis of monostatic radar data suggest little evidence for extensive ice signatures; however, initial analyses of bistatic data suggest that an ice signature may be observed within the crater Cabeus. These seemingly contradictory results could be related to the nature of the depth or distribution of ice. We will explore these possibilities, and the implications for lunar ISRU.  

How to cite: Jozwiak, L. and Patterson, G. W. and the Mini-RF Science Team: Mini-RF Observations of Lunar Polar Craters and Implications for Ice Distribution, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11285, https://doi.org/10.5194/egusphere-egu2020-11285, 2020.

EGU2020-18308 | Displays | GI3.2

A mission proposal for understanding the origin of the lunar water: Scientific concept of the SELPHIE Mission

Yoshifumi Futaana and Stas Barabash and the The SELPHIE mission proposal team

We are approaching a new era of space exploration: Utilization of our Moon for Human Beings. Intensive international efforts targeting human activities on the Moon have been initiated, and developed drastically in this decade. The revolution enabling the activities was the discovery of water at the Moon. We envisage utilizing the water for Lunar surface activities, as well as for explorations to farther Deep Space destinations.

Although multiple datasets have revealed the existence of Lunar water, fundamental scientific questions remain unanswered: Where has the surface and cold trap waters come from? What are the relative roles between solar wind protons and delivery from space for the Lunar surface water? What is the role of transportation of surface water to cold traps? This is the problem area that the SELPHIE (Surface, Exosphere, and Lunar Polar Hydration with Impact Experiments) mission is to reveal. The top-level science question of SELPHIE is "How is the lunar surface water delivered or produced, transported, and accumulated in cold traps?"

The baseline design of the SELPHIE mission is composed of six scientific sensors (three remote sensing and three in situ sensors) together with two impact experiments: An infrared spectrometer, visible camera, energetic neutral atom telescope, neutral mass spectrometer, solar wind monitor, and dust detector.  These sensors are operated from a 3-axis stabilized SELPHIE orbiter to reveal the comprehensive picture of the lunar water cycle. Two impact experiments (two identical systems, enabling two independent experiments) will be executed to reveal the source of water under cold traps. Each impact experiment contains a 6U cubesat and a small impactor (4 kg). The impactor will impact to a permanently shadowed crater to make ejecta. The cubesat will sound the plume by mass spectrometer and camera.

The norminal mission period is for 8-12 months, under the quasi-stationary polar orbit of the Moon (30-200 km altitudes). The pericenter is above the South Pole. The total mass of 600 kg (dry mass) with 61 kg payload mass is the baseline, while a further mass reduction could also be foreseen. The total cost, without payload developement, is within the ESA's F-class mission cost cap (150 MEuro).

How to cite: Futaana, Y. and Barabash, S. and the The SELPHIE mission proposal team: A mission proposal for understanding the origin of the lunar water: Scientific concept of the SELPHIE Mission, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18308, https://doi.org/10.5194/egusphere-egu2020-18308, 2020.

EGU2020-22678 | Displays | GI3.2

Lunar Volatile and Mineralogy Mapping Orbiter 12U Cubesat

Roman V. Kruzelecky, Piotr Murzionak, Qi-Yang Peng, Paul Burbulea, Ian Sinclair, Gregory Schinn, Yang Gao, Craig Underwood, Chris Bridges, Roberto Armellin, Andrea Luccafabris, Edward Cloutis, Alexis Parkinson, Brynn Dagdick, Mike Daly, Amélie St-Amour, and Jean de Lafontaine

Finding suitable quantities of key resources for life-support and refueling is vital to future sustained lunar manned bases and commercial activities. There are large uncertainties in the lunar near-surface distribution of water ice volatiles and relevant in-situ resources, such as ilmenite (FeTiO3). Moreover, planned future lunar orbiter missions have relatively limited spatial resolution, in the km range, for the volatile mappings relative to typical lander and rover range capabilities, especially for operations within the lunar Permanently Shadowed Regions (PSRs) that could shelter accumulated water ice deposits.

VMMO, for Volatile and Mineralogy Mapping Orbiter,  is a low-cost 20 kg 12U Cubesat that comprises the Lunar Volatile and Mineralogy Mapper (LVMM) multi-wavelength chemical lidar science payload, the Compact LunAr Ionizing Radiation Environment(CLAIRE) monitoring payload, a COTS electronics test bed, and the supporting 12U Cubesat bus with propulsion, direct to Earth S-band and 1560 nm optical communications, on board data processing and a suite of altitude and pointing sensors for semiautonomous vision-assisted navigation from lunar orbit.

VMMO will most likely be deployed from a commercial lunar transportation provider, such as Astrobotics, into a suitable near-polar injection orbit. The on-board propulsion will be used to achieve a stable lunar frozen orbit for the subsequent science operations with a perilune over the south pole under 100 km to assist the LVMM volatile and mineralogy mappings.

The compact LVMM is a multi-wavelength Chemical Lidar (<6.1 kg) which will use single-mode (SM) fiber lasers emitting simultaneously at 532 nm, 1064 nm and 1560 nm.  This will permit stand-off mapping of the lunar water ice distribution using active laser illumination, with a focus on selected permanently-shadowed craters in the lunar south pole;Shackleton, Faustini and Cabeus. This combination of selected laser spectral channels can provide very sensitive discrimination of water/ice in various types of Mare and Highland regolith, based on breadboard validation. The use of the SM fiber lasers enables a small laser beam divergence to provide high spatial resolution in the 10 m range at the lunar surface. There is some relevant flight heritage as part of the Fiber Sensor Demonstrator (FSD) payload on ESA’s Proba-2 spacecraft that is still operational after more than 10 years in low earth orbit.

LVMM can also be used in a passive multispectral mode at 300 nm, 532 nm, 1064 nm and 1560 nm to map the lunar ilmenite in-situ resource distribution during the lunar day using the characteristic surface-reflected solar illumination. By combining the passive lunar day measurements with the active lunar night measurements, some new insights into the lunar diurnal water cycle should be possible.

This paper discusses the VMMO science requirements and the supporting 12U Cubesat platform and LVMM multiwavelength chemical lidar payload and some of the associated design trade-offs.

How to cite: Kruzelecky, R. V., Murzionak, P., Peng, Q.-Y., Burbulea, P., Sinclair, I., Schinn, G., Gao, Y., Underwood, C., Bridges, C., Armellin, R., Luccafabris, A., Cloutis, E., Parkinson, A., Dagdick, B., Daly, M., St-Amour, A., and de Lafontaine, J.: Lunar Volatile and Mineralogy Mapping Orbiter 12U Cubesat, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22678, https://doi.org/10.5194/egusphere-egu2020-22678, 2020.

EGU2020-20527 | Displays | GI3.2

Newton novel magnetic instrument. Potential application to unveil key questions as the origin of the Moon

José Luis Mesa Uña, Marina Díaz Michelena, Francisco Javier de Frutos Hernánsanz, Claudio Aroca Hernández-Ros, Marina Pérez Jiménez, Marco Maicas Ramos, María del Mar Sanz Lluch, Cristina Lavín García, Reinel Marante, Benoit Langlais, Rolf Kilian, and Miguel Ángel Rivero

The main objective of this contribution is to present the evolution of NEWTON novel magnetic susceptometer for planetary exploration, a state of the art sensor for the measurement of the complex magnetic susceptibility developed in the frame of an EU H2020 funded project [1].

The magnetic susceptibility is a complex parameter dependent on the external magnetic field amplitude, direction and frequency. NEWTON susceptometer has been developed to determine the magnetic susceptibility of rocks and soils, with the capability to determine not only the real part but also the imaginary part of the susceptibility.

The calibration and validation process for the susceptometer prototype casted very good results in comparison with other commercial and high resolution laboratory devices, reaching a resolution in the order of χ = 10−4 (I.S. Vol. Susceptibility), representative of Earth, Moon and Mars rocks. The critical parts of the prototype have been subjected to different tests, i.e. vibration and TVT, to verify the capability to withstand the hard environmental conditions of interplanetary missions.

In this work we discuss the potential contribution of NEWTON instrument on the technical and scientific objectives achievement in future investigations on the Moon, either as payload during in-situ exploration with rovers or in sample return missions, providing a useful tool for fast in place sample analysis.

There are still open questions regarding Moon’s magnetic field and geological characteristics of the satellite. Most hypotheses to explain the magnetic characteristics and anomalies on the lunar surface invoke a thermally driven core dynamo during its Pre-Nectarian and Nectarian history [2]. However, this theory is problematical given the small size of the core and the required strong magnetic field strength of an ancient dynamo. Further investigations on the lunar samples from missions [3] indicate ancient magnetic fields with intensities of <1 to 120 μT for the period between 4.2 to 4.0 Ga. This huge range of intensities may indicate that the Moon’s magnetic field experienced extreme high temporal variations [2]. Even if considering large uncertainties, dynamo models should consider paleointensities of at least ~35 μT for this high-field period.

The use of scientific instruments like NEWTON susceptometer in rover exploration missions could shed some light on the ancient dynamo magnetic field, the magnetic and mineral composition of the lunar crust and other unanswered questions from the Moon.

Acknowledgements:

This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 730041 and the Spanish Programme of Research, Development and Innovation oriented to the challenges of the society under grant ESP2017-88930-R.

 

References:

[1] M.Diaz Michelena, J.L Mesa Uña, M. Perez Jimenez, M. Maicas Ramos, P. Cobos Arribas, C. Aroca Hernandez-Ros, Sensors and Actuators, A: Physical, volume 263, pages 471-479 (2017)

[2] Tikoo, S.M., Weiss, B.P., Cassata, W.S., Shuser, D.L., Gattacceca, J., Lima, E.A., Suavet, C., Nimmo, F. & Fuller, M.D. Earth Planet. Sci. Lett., 404: 89-97 (2014)

[3] Tsunakawa, H., Takahashi, F., Shimizu, H., Shibuya, H., & Matsushima, M. Icarus 228: 35-53 (2014).

[3] Fuller, M. (1974). Reviews of Geophysics, 12 – 1, 101-103 (1974)

How to cite: Mesa Uña, J. L., Díaz Michelena, M., de Frutos Hernánsanz, F. J., Aroca Hernández-Ros, C., Pérez Jiménez, M., Maicas Ramos, M., Sanz Lluch, M. M., Lavín García, C., Marante, R., Langlais, B., Kilian, R., and Rivero, M. Á.: Newton novel magnetic instrument. Potential application to unveil key questions as the origin of the Moon, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20527, https://doi.org/10.5194/egusphere-egu2020-20527, 2020.

All lunar swirls are known to be co-located with crustal magnetic anomalies (LMAs). Not all LMAs can be associated with albedo markings, making swirls, and their possible connection with the former, an intriguing puzzle yet to be solved.

Given favorable conditions, an LMA can deflect the solar wind enough to form a mini-magnetosphere that partially (and possibly only temporarily) shields the underlying lunar regolith. Recent modeling efforts have shown that the resulting energy flux pattern to the surface is consistent with the underlying albedo (swirl) patterns. In particular, coupling a fully kinetic particle-in-cell code with a downward-continued magnetic field model based on orbital-altitude observations, we are able to produce a pattern similar to Reiner Gamma’s alternating bright and dark bands, but only when integrating over the full lunar orbit. Although consistent with the solar-wind standoff hypothesis for the origin of swirls, the match is not perfect. A combination of reasons could be the cause.

Here we discuss some of the unexplained discrepancies between the flux profile and the surface brightness and why the Reiner Gamma swirl region should be a prime target for future low-orbiting spacecraft or even landers/rovers, and we consider the potential role of human exploration.

How to cite: Deca, J.: The Reiner Gamma Swirl and Magnetic Anomaly: Why We Should Go There, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6194, https://doi.org/10.5194/egusphere-egu2020-6194, 2020.

EGU2020-22416 | Displays | GI3.2

European Lunar Cargo Lander: Performance figures and community opportunities

Robert Buchwald, Silvio Sandrone, Thomas Schrage, and Carlo Mirra

The European Large Logistic Lander (EL3) is an ESA proposed contribution to the international human Moon exploration efforts. EL3 would be capable of flying a variety of missions. In the frame of the American Artemis program, EL3 would provide increased capabilities for science and technology payloads as well as supporting lunar surface asset deployment for longer surface expeditions. Besides this, also self-standing European science and exploration missions as well as a sample return scenario using gateway and Orion infrastructure for returning surface samples from the lunar far side back to Earth are part of the lander's portfolio.

Being envisaged as a modular and versatile system, payloads could be delivered to any longitude or latitude on the Moon. Hazard avoidance capabilities would enable accessing clustered and rocky areas on the surface, which were out of reach for missions of the past. Lunar night survival technologies could allow long term science observations and repeated operations of ISRU plants.

ESA is in exchange with the international community on the definition of common user requirements which address NASA's needs whilst also expressing the European vision. First industrial studies have been awarded for paving the way towards a sustained exploration of the Moon. A regular exchange between the EL3 user community and the industrial teams is planned to be organized soon to allow capturing all relevant stakeholder needs right from the beginning.

How to cite: Buchwald, R., Sandrone, S., Schrage, T., and Mirra, C.: European Lunar Cargo Lander: Performance figures and community opportunities, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22416, https://doi.org/10.5194/egusphere-egu2020-22416, 2020.

EGU2020-11595 | Displays | GI3.2

PRO-ACT - Planetary Robots Deployed for Assembly and Construction of Future Lunar ISRU and Supporting Infrastructures

Luís Lopes, Shashank Govindaraj, Balazs Bodo, Kevin Picton, Joseph Purnell, Fran Colmenero, Wiebke Brinkmann, Heitor Savino, Jakub Stelmachowski, and Nabil Aouf

PRO-ACT (Horizon 2020; https://www.h2020-pro-act.eu/) studies the establishment of a lunar base with the support of a mobile robotic platform formed by three distinct robots, with different features, based on their cooperation and manipulation capabilities. This vision will provide tools in preparation of the commercial exploitation of in-situ resources by assembling an ISRU (In-Situ Resource Utilisation) system, essential for a future human settlement at the Moon. PRO-ACT’s vision of ISRU focuses on the extraction of oxygen from lunar regolith to serve as the oxidizer for fuel and artificial atmosphere generation within habitats and 3D printing of relevant structures using regolith for construction purposes – including tiles for roads and elements for shelters. The mineral ilmenite, found in lunar rocks, is the perfect target for the ISRU platform as it contains oxygen, iron and titanium as construction materials.

The main goal of PRO-ACT is to implement and demonstrate the cooperative capabilities of the multi-robot system in a Moon alike environment that will be replicated at two sites, indoors and outdoors, in Europe. For this purpose, the PRO-ACT project (OG11) will also rely on the outcomes of previous space-related projects from the PERASPERA project and its Operational Grants. Therefore, PRO-ACT will: 1) Review, extend and integrate previous OGs outcomes as part of a comprehensive multi-robot system, in a Moon construction scenario, 2) Develop robust cooperation capabilities allowing joint interventions (navigation in close vicinity and joint manipulation actions) in mixed structured/unstructured environment, 3) Make the capabilities available within a CREW module, 4) Customize existing mobile robotic platforms and prepare facilities to perform tests and demonstrations in a selection of relevant scenarios of Moon construction activities (ISRU capabilities establishment; preparing dust mitigation surfaces; assembling and deploying a gantry/3D printer).

PRO-ACT will show what robotic cooperation can achieve and will demonstrate the effectiveness of collaborative mission planning, and manipulation and assembly of a supporting infrastructure. Cooperative scenarios will be based on: 1) fine scale surveying of areas prior to construction work, 2) site clearing by grading stones and debris, 3) unloading equipment/construction elements and transporting them to the assembly sites, 4) assembly of specific modular components of an ISRU plant, 5) assisting partial assembly and mobility of a gantry, 6) 3D printing of modular building elements from pseudo-regolith simulant, and 7) sample assembly of printed elements to construct sections of storage, habitation spaces or dust mitigation surfaces. Following this scenario, the key robotic elements, (the mobile rover IBIS, the six-legged walking robot Mantis and a gantry) are outlined according to the corresponding mission architecture. The ISRU plant size is representative of a future lunar mission, with grasping points to assist robotic manipulation capabilities and considering reduced lunar gravity.

The target of this work is to reach a Technology Readiness Level of TRL 4/5 (depending on scenarios subparts) with this approach, to enable exploration of the Moon environment in the next decade. This will be achieved and proven with the performance of the required tests and demonstrations in Lunar analogues, in order to validate the newly developed capabilities.

How to cite: Lopes, L., Govindaraj, S., Bodo, B., Picton, K., Purnell, J., Colmenero, F., Brinkmann, W., Savino, H., Stelmachowski, J., and Aouf, N.: PRO-ACT - Planetary Robots Deployed for Assembly and Construction of Future Lunar ISRU and Supporting Infrastructures, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11595, https://doi.org/10.5194/egusphere-egu2020-11595, 2020.

EGU2020-20287 | Displays | GI3.2

Retrieving paleopoles using newly mapped lunar magnetic anomalies within basins

Joana S. Oliveira and Lon L. Hood

Orbital spacecraft magnetic field observations show that several isolated magnetic anomalies are found to be heterogeneously distributed over the lunar surface. The magnetic anomalies origin is still debated; however, it is largely accepted that an ambient core magnetic field was present during their formation. Contrary to previous studies, here we focus only on anomalies that are related to basins/craters, which correspond to the best possibility to hold ancient core field information. In particular, the basin rocks become thermoremanently magnetized as the melt sheet cools down slowly recording the ambient magnetic field that was present when the crater was formed.

We build regional magnetic field maps using data from quiet orbits of Lunar Prospector and Kaguya spacecraft. When comparing these regional maps to existing global models, several differences and details are discovered. Further investigation is required to understand why small scales are missing from global models. For each mapped crater, we perform inversions for the magnetization direction to estimate the corresponding paleopole position (defined as the north magnetic pole when the anomaly formed). In detail, a grid of dipoles is placed over the basin inner depression, where the melt sheet is believed to be. All dipoles have the same common direction, nonetheless different dipole moments.

Preliminary results show that paleopole positions of regionally mapped anomalies associated with craters are not in absolute agreement with previous paleopole studies. Also of significance is the distribution of dipoles obtained, which seem to be consistent with inferred impactor trajectories. We conclude that paleopole position results are highly dependent on the technique and choices we make to construct the magnetic field maps. Further studies of several other craters will be performed, but we expect large differences when using regionally mapped anomalies. Our results will help to better constrain the lunar ancient core field morphology.

How to cite: Oliveira, J. S. and Hood, L. L.: Retrieving paleopoles using newly mapped lunar magnetic anomalies within basins, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20287, https://doi.org/10.5194/egusphere-egu2020-20287, 2020.

Our previous study of the restored Apollo Lunar Surface Magnetometer (LSM) data discovered that narrowband ion cyclotron waves were often observed at the Apollo 15 and 16 landing sites when the Moon was in the Earth’s magnetotail (Chi et al., 2013). Two mechanisms have been proposed to explain the excitation of ion cyclotron waves at the Moon: the absorption of ions at the lunar surface and the pickup ions from the lunar exosphere. Either process can lead to an ion velocity distribution unstable to ion cyclotron instability, but it is of particular interest to investigate which ion cyclotron waves are associated with the latter mechanism so that the observations of them can provide hints to the type and the number of pickup ions escaped from the lunar exosphere. More recently, Nakagawa et al. (2018) examined the Kaguya data and found similar ion cyclotron waves in the Earth’s magnetotail but at a very low occurrence rate.

In this study, we perform statistical analysis on the full set of the restored LSM data, including those from the Apollo 12, 15, and 16 missions between 1969 and 1975, that were only partially available to our previous study. We find that the ion cyclotron waves were observed by Apollo 15 LSM approximately 5% of the time, which is about six times more frequently than that found in Kaguya observations. A slightly lower occurrence rate of ion cyclotron waves is found in the Apollo 16 LSM data because of the strong local crustal magnetic field at the Apollo 16 site and the conservation of the Poynting flux. Future joint measurements by lunar landers and orbiters can enable a true comparison of the ion cyclotron waves on the lunar surface and at different altitudes of the exosphere.

How to cite: Armstrong, C. and Chi, P.: Ion Cyclotron Waves on Lunar Surface: Apollo Observations and Implications for Future Lunar Missions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20818, https://doi.org/10.5194/egusphere-egu2020-20818, 2020.

EGU2020-21638 | Displays | GI3.2

DUSTER: a multi-sensor instrument to study dust transport and electrostatic removal for exploration missions

Sylvain Ranvier, Sebastien Hess, Jean-Charles Mateo Velez, Angel Alvaro Sanchez, and Johan De Keyser

One major environmental constraint during exploration missions is the presence of charged dust-like particles, which are present on the Moon, Mars, comets and asteroids. From an analysis of the effects of lunar dust on Extra-Vehicular Activity (EVA) systems during the six Apollo missions that landed on the lunar surface, it was found that these effects can take many forms such as external vision obscuration, false instrument readings, dust coating and contamination, loss of traction, clogging of mechanisms, abrasion, thermal control problems and seal failures. One of the most serious effects is the compromising of astronaut health by irritation and inhalation of lunar dust.

Therefore, it is of utmost importance to characterise the properties of the dust particles present on the exploration sites and their transportation mechanisms to enable efficient mitigation techniques to be put in place.

The overall objective of the DUSTER project is to develop instrumentation and technologies to study dust particles and electrostatic transportation for planetary and small body exploration missions. Specifically, the aim is to design, manufacture and test in a relevant environment a compact multi-sensor instrument for in situ analysis of dust properties (mechanical and electrical) and electrostatic transportation that can be used on a small lunar lander. To that end, the instrument includes:

- A dust collector: electrodes biased at high potential to attract/collect dust particles, coupled to an electrometer

- Langmuir probes

- E-field probes

Using this instrument, the following parameters will be derived:

- Charging level of dust as a function of the environmental parameters (illumination, plasma density and temperature)

- (gravity + cohesive forces)/charge ratio distribution of dust layer

These two parameters will allow the determination of the electric field needed to attract/collect dust according to the environmental conditions (illumination, plasma density and temperature), which, among other applications, will allow designing electrostatic dust mitigation devices and dust sample collectors.

How to cite: Ranvier, S., Hess, S., Mateo Velez, J.-C., Alvaro Sanchez, A., and De Keyser, J.: DUSTER: a multi-sensor instrument to study dust transport and electrostatic removal for exploration missions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21638, https://doi.org/10.5194/egusphere-egu2020-21638, 2020.

EGU2020-22244 | Displays | GI3.2

The ESA Prospect Payload for Luna 27: Development Status

David Heather and Elliot Sefton-Nash

Introduction

The Package for Resource Observation and in-Situ Prospecting for Exploration, Commercial exploitation and Transportation (PROSPECT) is a payload in development by ESA for use at the lunar surface. Current development is for flight on the Russian-led Luna-Resource Lander (Luna 27) mission, which will target the south polar region of the Moon. PROSPECT will perform an assessment of volatile inventory in near surface regolith (down to ~ 1 m), and analyses to determine the abundance and origin of any volatiles discovered. Lunar polar volatiles present compelling science and exploration objectives for PROSPECT, but solar wind-implanted volatiles and oxygen in lunar minerals (extracted via ISRU techniques) constitute potential science return anywhere on the Moon, independently of a polar landing site. PROSPECT is comprised of the ProSEED drill module and the ProSPA analytical laboratory plus the Solids Inlet System (SIS), a carousel of sealable ovens (for evolving volatiles from regolith).

In ensemble, PROSPECT has a number of sensors and instruments (including ion-trap and magnetic sector mass spectrometers, imagers, and sensors for temperature, pressure, and permittivity) that form the basis for a range of science investigations that are (almost all) led by the PROSPECT Science Team:

  • Imaging, Surface Modelling and Spectral Analysis
  • Drilling, Geotechnics and Sample Handling
  • ProSPA ISRU Precursor Experiments
  • ProSPA ISRU Prospecting
  • ProSPA Light Elements & Isotopes
  • ProSPA Noble Gases
  • Thermal Environment and Volatile Preservation
  • Permittivity (ESA-led)

Development status and current activities

PROSPECT Phase C, ‘detailed definition’, began in December 2019. An plan of research activities is in progress to gain from and guide ongoing development, build strategic scientific knowledge, and to prepare for operation of the payload.

Drill Testing. Testing of the ProSEED Development Model was carried out in December 2019 as part of the final Phase B activities. Test procedures were formulated to demonstrate drilling and sampling functionality in ambient, cold and thermal vacuum (TV) laboratory conditions (at CISAS, University of Padova). Tests included drilling into, and sampling from, well-characterized NU-LHT-2M simulant mixed with anorthosite inclusions of various sizes, according to a layered scheme that describe depth-density profile and distribution of inclusions and a range of plausible water ice contents.

ProSPA Bench Development Model (BDM). The BDM of the ProSPA analytical lab at the Open University has been tested to demonstrate science performance against measurement requirements. Dedicated efforts in 2019 focused on verification of evolved gas analysis (EGA) via measurement of meteorite standards, constraint of oxygen yield via demonstration of ISRU capabilities, improving understanding of sensitivity of science requirements to regolith volatile abundance and possible contamination, and understanding the performance of oven seal materials.

Volatile Preservation. Particular efforts since 2018 have focused on understanding the capability of PROSPECT to sufficiently preserve volatile content in regolith throughout the sampling-analysis chain: from drilling to sealing of the ovens, until measurement of evolved gases in ProSPA’s ion-trap and magnetic sector mass spectrometers. PROSPECT’s ability to meet science requirements must persist for the range of possible volatile contents expected in near-surface regolith at landing sites in the lunar south polar region.

How to cite: Heather, D. and Sefton-Nash, E.: The ESA Prospect Payload for Luna 27: Development Status, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22244, https://doi.org/10.5194/egusphere-egu2020-22244, 2020.

EGU2020-22568 | Displays | GI3.2

Building a European Lunar Capability with the European Large Logistic Lander

Nick Gollins, Shahrzad Timman, Max Braun, and Markus Landgraf

In the context of an accelerated lunar exploration agenda on international level, ESA is engaging in studies to enable European roles in the near and mid-term which can support the international community. While near-term opportunities exist in “boots-on-the-ground” human lunar return in the frame of the NASA Artemis programme and commercial (CLPS) robotic landers, ESA continues to prepare the next step in sustainability with the European Large Logistic Lander (EL3).

Returning to the Moon not only yields fundamentally important science opportunities for our understanding of the Solar System but also allows us to test hardware and operational procedures for the exploration and utilization of space beyond Low Earth Orbit (LEO). EL3 will be a sustainable programme that will allow a diversity of missions for the science community. Whilst EL3 is intended to be a generalised lander capable of delivering a wide variety of cargo, such as science experiments, crew supplies, or unpressurised rovers, the most studied mission to date is a sample return package comprised of a return stage and a rover. EL3 Sample Return will land on the lunar surface, demonstrate surface operations, and return ∼15 kg of samples to the lunar Gateway and back to Earth by the astronauts aboard Orion. Hence, the mission will begin a robotic pathway toward sustainable human exploration of the Moon and beyond. 

To achieve this, some of the key objectives include: (1) Create opportunities for science, particularly sample return, which has been highlighted as a key aspect of ESA’s lunar science strategy; (2) Gain scientific and exploration knowledge by scouting for potential resources; (3) Create opportunities to demonstrate and test technologies and operational procedures for future Mars missions; (4) Preparing for more sustainable human lunar missions by implementing, demonstrating, and certifying technology elements for vehicle reusability, mobility, and night survival.

EL3 Sample Return will consist of the EL3 cargo lander, an interface element housing a 330 kg rover, and a Lunar Ascent Element (LAE) that will return the samples to the lunar Gateway. The rover will be designed for driving more than 100 km at relatively high speed and surviving the lunar night. Whilst mostly operated by ground control on Earth, the rover could also be partly tele-operated by astronauts aboard the Gateway. Once landed on the lunar surface, the rover will immediately collect a contingency sample and will then collect additional samples along a ∼35 km long traverse. The rover will carry a suite of scientific instruments that will allow the comprehensive study of the sampling locations, providing the context of the samples, as well as the geology along the traverse. After depositing the samples into the LAE, the rover will embark on a 100+ km traverse along which it will take further in-situ measurements over the course of a year or more.

In summary, the goals of the EL3 programme will be to support international crewed lunar activities, develop and fly the technologies necessary to build Europe’s lunar capability, and serve the needs of the lunar science community.

 

How to cite: Gollins, N., Timman, S., Braun, M., and Landgraf, M.: Building a European Lunar Capability with the European Large Logistic Lander, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22568, https://doi.org/10.5194/egusphere-egu2020-22568, 2020.

ILEWG has been organising since 1994 ICEUM International Conferences on Exploration & Utilisation of the Moon with published proceedings, and where community declarations have been prepared and endorsed by community participants. ILEWG has co-organised and co-sponsored lunar sessions at EGU, COSPAR, EPSC.

ILEWG task groups include science, technology, human aspects, socio-economics, young explorers and outreach, programmatics, roadmaps and synergies with Mars exploration, MoonBase, MoonVillage, EuroMoonMars, ArtMoonMars, Young Lunar Explorers, ILEWG Young Professional Grantees.  ILEWG has also sponsored a number of activities, workshops, tasks groups and publications in collaborations with other organisations: COSPAR, space agencies, IAA, IAF, EGU

Besides the discussion forums, users can also obtain information on how to participate, as well as details on the latest news and events regarding lunar exploration, forthcoming meetings, relevant reports and documents of importance for the work of the ILEWG, summary descriptions of recent and future  lunar exploration projects (such as SMART-1, Chang'E1-5 , Selene Kaguya, Chandrayaan-1-2, LRO, LCROSS), GRAIL, ARTEMIS, international lunar exploration projects) funded by various space agencies, and basic data on the Moon itself. Activities of the related space agencies and organizations can also be found. The ILEWG Forum also hosts the Lunar Explorer's Society. http://www.lunarexplorers.net/

The International Lunar Exploration Working Group (ILEWG) is a public forum sponsored by the world's space agencies to support "international cooperation towards a world strategy for the exploration and utilization of the Moon - our natural satellite" (International Lunar Workshop, Beatenberg (CH), June 1994). The Forum is intended to serve three relevant groups:

  • Actual members of the ILEWG, i.e. delegates and representatives of the participating Space Agencies and organizations - allowing them to discuss and possibly harmonize their draft concepts and plans in the spirit of the Beatenberg Declaration (see below).
  • Team members of the relevant space projects - allowing them to coordinate their internal work according to the guidelines provided by the ILEWG Charter (see below).
  • Members of the general public and of the Lunar Explorer's Society who are interested and wish to be informed on the progress of the Moon projects and possibly contribute their own ideas.

https://en.wikipedia.org/wiki/International_Lunar_Exploration_Working_Group

https://moonbasealliance.com/ilewg

ILEWG ICEUM declarations (International Conference on Exploration & Utilisation of the Moon) :

https://ui.adsabs.harvard.edu/search/q=ilewg%20declarations&sort=date%20desc%2C%20bibcode%20desc&p_=0

COSPAR ICEUM13: Pasadena Lunar Declaration 2018 https://meetingorganizer.copernicus.org/EPSC-DPS2019/EPSC-DPS2019-874-1.pdf

Report from ILEWG and Cape Canaveral Lunar Declaration 2008 https://meetingorganizer.copernicus.org/EGU2009/EGU2009-13223.pdf

How to cite: Foing, B. and the ILEWG Task Groups: Report from ILEWG Task Groups: Science, Technology, human aspects, roadmaps, socio-economics, young lunar explorers, MoonVillage, MoonMars synergies, EuroMoonMars, ArtMoonMars, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22025, https://doi.org/10.5194/egusphere-egu2020-22025, 2020.

EGU2020-20496 | Displays | GI3.2

The Human Factors of Additive Manufacturing on Human Extra-Terrestrial Missions

Sabrina Kerber, Michaela Musilova, and Bernard Foing

Introduction
Additive manufacturing technologies have been successfully implemented in the concept designs for human interplanetary missions for some years. They not only play an important role in the designs of future-extra-terrestrial habitats, but the benefits of 3D printing have already been successfully tested on the International Space Station (ISS). [1] 
However, while such studies of in-situ manufacturing techniques concentrate heavily on applications in the area of engineering or on the potential of 3D printing sustenance, they regretfully neglect to explore the potential benefits additive manufacturing could have for the Human Factors of space exploration. [1, 2]
Based on experiments during a lunar simulation at the Hawai´i Space Exploration Analog and Simulations (HI-SEAS) habitat, this paper investigates how additive manufacturing can improve liveability in a space habitat.
Personal objects and leisure time items are indispensable for manned space exploration, as they greatly contribute to the astronauts’ mental health and psychosocial balance. Access to a 3D printer bears the potential of a much greater flexibility and variety in personal items, and could also offer the possibility to customize leisure objects to specific needs and moods of astronauts. In addition, through the limited payloads and possibilities of recycling everyday objects, additive manufacturing technology offers the opportunity to greatly enhance the sustainability the of any human extra-terrestrial mission.

Methodology
In December 2019 the European Space Agency’s (ESA) EuroMoonMars (EMM) and International Lunar Exploration Working Group (ILEWG) initiated an analog astronaut simulation in cooperation with the International MoonBase Alliance (IMA). During this mission (EMMIHS-II - EuroMoonMars IMA HI-SEAS) the Human Factors of Additive Manufacturing Study was conducted as a basis for this paper. Psychological effects, changes in mood and work effectiveness, and the possibility to create and maintain a connection to Earth by 3D printing seasonal objects and decorations, were assessed.
The study delivered positive results about the use of additive manufacturing from a Human Factors point of view, as well as the confirmation of the use in engineering. The results open up the possibilities for further studies of the Human Factors of additive manufacturing during future analog simulations.

Acknowledgements
First, I would like to thank our fellow EMMIHS-II crew members (M. Musilova, A. J. D’Angelo, A. P. Castro de Paula Nunes, C.R. Pouwels) and the EMMIHS-II mission sponsors. In addition, my gratitude goes out to the HI-SEAS Mission Control, ground support at ESA/ESTEC and the ILEWG EuroMoonMars manager, Prof. B. H. Foing, for enabling this research.

 

References:
[1] T. Prater et al (2019), Overview of the In-Space Manufacturing Technology Portfolio, NASA & ISS National Lab Microgravity Materials Science Workshop, Georgia, US.
[2] M. Terfansky, M. Thangavelu (2013), 3D Printing of Food for Space Missions, California, US.
[3] M. Musilova, H. Rogers, B. H. Foing et al (2019). EMM IMA HI-SEAS campaign February 2019. EPSC-DPS2019-1152.
[4] EuroMoonMars Instruments, Research, Field Campaigns and Activities 2017-2019. B. H. Foing, EuroMoonMars 2018-2019 Team. 2019 LPI Contrib. No. 3090.

How to cite: Kerber, S., Musilova, M., and Foing, B.: The Human Factors of Additive Manufacturing on Human Extra-Terrestrial Missions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20496, https://doi.org/10.5194/egusphere-egu2020-20496, 2020.

Outer space activities are increasingly bringing the international (scientific) community to upper stages of knowledge and awareness. With particular reference to Lunar exploration, general involvement of all States (also within a context of public-private partnerships initiatives) towards the principle of sustainable utilization of lunar resources shall represent an important requirement for the future of all Mankind


Thus, the safeguarding of lunar environment (the equitable/intragenerational utilization of its resources) shall represent a critical issue for the whole evolutionary framework of the Corpus Iuris Spatialis

Firstly, the principle herein shall be taken into examination under the provisions laid down in the Agreement governing the Activities of States on the Moon and other Celestial Bodies. Accordingly, article 11 states “the moon and its natural resources are the common heritage of mankind”[..]; as well, “The moon is not subject to national appropriation by any claim of sovereignty, by means of use or occupation, or by any other means..” (paragraph 2)

 
Secondly, other concerns may also take into account: a) the perspective of ISRU (in situ resources utilization) processes, which shall take place towards sustainability means b) the undertaking of well balanced measures in exploring and using natural resources vis-à-vis adverse changes in lunar environment (article 7, par. 1, Moon Treaty). In addition, besides the terms pursuant to the establishment of peaceful use of (space) lunar activities, an adequate consensus shall be called upon States beyond the status quo

  
In conclusion, the aferomentioned background shall also consider the adoption of a comprehensive Additional Protocol to the Moon Treaty concerning the sustainable utilization of lunar resources. Arguably, this progressive framework may also be welcomed as milestones towards further legal developments in international space law 

 

 

How to cite: De Blasi, D.: The Future of Sustainable utilization of resources on the Moon: a new international legal regime? , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2018, https://doi.org/10.5194/egusphere-egu2020-2018, 2020.

EGU2020-8067 | Displays | GI3.2

Simultaneous retrieval of the lunar solid body tide and topography from laser altimetry

Robin Thor, Reinald Kallenbach, Ulrich Christensen, Philipp Gläser, Alexander Stark, Gregor Steinbrügge, and Jürgen Oberst

The Moon is periodically deformed by the tidal forces exerted on it by the Earth and the Sun. The tidal Love number h2 describes the magnitude of the radial component of these deformations at the monthly frequency, which have an amplitude of up to ∼10 cm. Like the potential Love number k2, h2 depends on the density and rheological properties of the materials in the lunar interior and their distribution. We analyze > 3.6 · 109 measurements of the Lunar Orbiter Laser Altimeter (LOLA) obtained during the 27-month circular orbit phase of the Lunar Reconnaissance Orbiter (LRO) at 50 km altitude, when LOLA reached global coverage. We simultaneously invert these observations for the Love number h2 and a global topographic model. The topography is parametrized as an expansion in 2D cubic B-spline basis functions, which are defined on a global equirectangular grid. This parametrization is more computationally efficient than an expansion in spherical harmonics, but still allows for a high smoothness. To deal with data gaps, we constrain the solution by minimizing the second derivative of the topography. We find that the h2 solution depends on the choice of resolution of the equirectangular grid. We determine the accuracy for each investigated resolution (from 6 km to 1 km at the equator) from a Monte Carlo simulation using 100 synthetically generated sets of observations. The topographic signal in the synthetic data follows a power law extrapolated from the real lunar topography. At large scales, the topography is generated using a spherical harmonic expansion, at smaller scales it is generated using Gaussian process regression. Finally, we use the inverse of the root-mean-square h2 obtained from the Monte Carlo simulation as weights for determining a weighted mean of the h2 results for different grid resolutions. The final result of h2 = 0.0386 ± 0.0022 agrees within one standard deviation with a previous result obtained from the same data, but utilizing crossover points of LOLA profiles. This validates the method of simultaneous inversion for tides and topography, especially with regard to future laser altimeter experiments at other planetary bodies, such as Mercury and Ganymede. However, our result also confirms a discrepancy between laser altimeter measurements of h2 and the k2 result of the Gravity Recovery and Interior Laboratory (GRAIL) mission, which needs to be resolved through better modelling of the lunar tidal response.

How to cite: Thor, R., Kallenbach, R., Christensen, U., Gläser, P., Stark, A., Steinbrügge, G., and Oberst, J.: Simultaneous retrieval of the lunar solid body tide and topography from laser altimetry, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8067, https://doi.org/10.5194/egusphere-egu2020-8067, 2020.

GI3.4 – Calibration and validation of Earth satellite measurements

EGU2020-10539 | Displays | GI3.4

Overview of the 2019 Sentinel-5p TROpomi vaLIdation eXperiment (TROLIX)

Arnoud Apituley, Karin Kreher, Ankie Piters, John Sullivan, Michel vanRoozendael, Tim Vlemmix, Mirjam den Hoed, Arnoud Frumau, Bas Henzing, Bart Speet, Jan Vonk, Pepijn Veefkind, Diego Alves, and Alexandre Cacheffo and the TROLIX-Team

For the validation of Sentinel-5p/TROPOMI the TROpomi vaLIdation eXperiment (TROLIX) was held in the Netherlands based at the Cabauw Experimental Site for Atmospheric Research during September 2019. TROLIX consisted of active and passive remote sensing platforms in conjunction with several balloon-borne and surface measurements.

The intensive observations will serve to establish the quality of TROPOMI L2 main data products (UVAI, Aerosol Layer Height, NO2, O3, HCHO, Clouds) under realistic conditions with varying cloud cover and a wide range of atmospheric conditions.

Since TROPOMI is a hyperspectral imager with a very high spatial resolution of 3.6 x 5.6 km2, understanding local effects such as inhomogeneous sources of pollution, sub-pixel clouds and variations in ground albedo is important to interpret TROPOMI results. Therefore, the campaign included sub-pixel resolution local networks of sensors, involving MAXDOAS and Pandora instruments, around Cabauw (rural) and within the city of Rotterdam (urban). Utilising its comprehensive in-situ and remote sensing observation program in and around the 213 m meteorological tower, Cabauw was the main site of the campaign with focus on vertical profiling using lidar instruments for aerosols, clouds, water vapor, tropospheric and stratospheric ozone, as well as balloon-borne sensors for NO2 and ozone.

The data set collected can be directly compared to the TROPOMI L2 data products, while measurements of parameters related to a-priori data and auxiliary parameters that infuence the quality of the L2 products such as aerosol and cloud profiles and in-situ aerosol and atmospheric chemistry were also collected.

This paper gives an overview of the campaign, and an overview of the participating main and ancillary instrumentation and preliminary results.

Future activities include the deployment in 2020 of an airborne hyperspectral imager.

How to cite: Apituley, A., Kreher, K., Piters, A., Sullivan, J., vanRoozendael, M., Vlemmix, T., den Hoed, M., Frumau, A., Henzing, B., Speet, B., Vonk, J., Veefkind, P., Alves, D., and Cacheffo, A. and the TROLIX-Team: Overview of the 2019 Sentinel-5p TROpomi vaLIdation eXperiment (TROLIX), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10539, https://doi.org/10.5194/egusphere-egu2020-10539, 2020.

EGU2020-20671 | Displays | GI3.4

Validation activities for the Ice, Cloud, and Land Elevation Satellite - 2 (ICESat-2) Mission

Thomas Neumann, Kelly Brunt, Lori Marguder, and Nathan Kurtz

After launching on 15 September 2018, the Ice, Cloud, and Land Elevation Satellite – 2 (ICESat-2) Mission began collecting data on 14 October 2018.  The mission uses green laser light emitted by the Advanced Topographic Laser Altimetry System (ATLAS) to detect individual photons that are reflected by the Earth’s surface and returned to ATLAS.  These photons, when combined with information on the pointing direction, and position of the observatory in space, provide a geolocation and elevation for every measurement that spans the globe from 88 degrees north latitude to 88 degrees south.  The Global Geolocated Photon data product provides a latitude, longitude, elevation, and measurement time for each photon event telemetered to Earth for each of the instrument’s six beams. This product also delineates between high, medium, and low signal confidence levels and those measurements associated with background noise. The higher level, along-track products each use different strategies for photon aggregation to optimize the precision and accuracy of the surface retrievals over specific surface types. These types include land ice, sea ice, vegetation/land, ocean, and inland water. There is a separate channel dedicated to atmospheric returns to measure cloud and aerosols over a vertical window of 15 km. Calibration efforts utilized well designed on-orbit maneuvers to identify both pointing and range biases attributed to orbital variations on the satellite. Once corrected, the science-quality data products were released to the public in May 2019.

 

In this presentation, we will present our ongoing work to evaluate and validate the geolocation and elevation accuracy and precision of measurements provided by the ICESat-2 mission.  The approaches are diverse in both location and methodology to ensure that we have a comprehensive assessment of the ATLAS performance variations throughout the orbital cycles. These strategies include comparisons with ground-based and airborne elevation measurements over the ice sheets, detailed analysis of returns from well-surveyed corner cube retro-reflectors, comparison of sea ice freeboard measured by airborne lidars, evaluation of global-scale ocean elevation through comparison with radar altimeters, and comparison of vegetation canopy height metrics measured by airborne lidar.  Our work to date demonstrates that individual photon elevations are accurate to approximately 30 cm vertically, and 6 m radially.  Aggregating many photons together reduces the elevation uncertainty to less than 5 cm for relatively flat and smooth ice sheet interiors.

How to cite: Neumann, T., Brunt, K., Marguder, L., and Kurtz, N.: Validation activities for the Ice, Cloud, and Land Elevation Satellite - 2 (ICESat-2) Mission, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20671, https://doi.org/10.5194/egusphere-egu2020-20671, 2020.

EGU2020-21378 | Displays | GI3.4

Calibration and Validation of Microwave Atmospheric Sounders on CubeSats and Small Satellites for Applications in Weather Prediction and Climate Monitoring

Steven C. Reising, Wesley Berg, Shannon T. Brown, Todd C. Gaier, Christian D. Kummerow, Venkatchalam Chandrasekar, Sharmila Padmanabhan, Boon H. Lim, Richard Schulte, Yuriy Goncharenko, and Chandrasekar Radhakrishnan

Passive microwave radiometer systems have provided both temperature and water vapor sounding of the Earth’s atmosphere for several decades, including MSU, AMSU, MHS, ATMS, etc.  Due to its ability to penetrate clouds, dust, and aerosols, among global datasets, microwave atmospheric sounding provides the most valuable quantitative contribution to weather prediction.  Long-term, well-calibrated sounding records can be indispensable for climate measurement and model initialization/validation.  Hence, passive microwave sounders are deployed on large, operational satellites and operated by NOAA, EUMETSAT and other similar national/international organizations.

In the past five years or so, advances in CubeSats and other small satellites have enabled highly affordable space technology, providing access to space to private industries, universities and smaller nations.  This provides a valuable opportunity for organizations such as NOAA and EUMETSAT to explore the added value of acquiring data from passive microwave sounders on small, low-cost spacecraft for relatively small investments, both for sensor and spacecraft acquisition and launch.  This provides the potential for deployment of constellations of low-Earth orbiting microwave sounders to provide much more frequent revisit times than are currently available.

For passive microwave sounding data to be valuable for weather prediction and climate monitoring, each sensor needs to be calibrated and validated to acceptable accuracy and stability.  In this context, the first CubeSat-based multi-frequency microwave sounder to provide global data over a substantial period is the Temporal Experiment for Storms and Tropical Systems Demonstration (TEMPEST-D) mission.  This mission was designed to demonstrate on-orbit capabilities of a new, five-frequency millimeter-wave radiometer to enable a complete TEMPEST mission using a closely-spaced train of eight 6U CubeSats with identical low-mass, low-power millimeter-wave sensors to sample rapid changes in convection and surrounding water vapor every 3-4 minutes for up to 30 minutes.  TEMPEST millimeter-wave radiometers scan across track and observe at five frequencies from 87 to 181 GHz, with spatial resolution ranging from 25 km to 13 km, respectively.

The TEMPEST-D satellite was launched on May 21, 2018 from NASA Wallops to the ISS and was successfully deployed on July 13, 2018, into a 400-km orbit at 51.6° inclination.  The TEMPEST-D sensor has been operating nearly continuously since its first light data on September 5, 2018.  With more than 16 months of operations to date, TEMPEST-D met all of its Level-1 mission objectives within the first 90 days of operations and has successfully achieved TRL 9 for both instrument and spacecraft systems. 

Validation of observed TEMPEST-D brightness temperatures is performed by comparing to coincident observations by well-calibrated on-orbit instruments, including GPM/GMI and MHS on NOAA-19, MetOp-A and MetOp-B satellites. Absolute calibration accuracy is within 0.9 K for all except the 164 GHz channel, well within the required 4 K for all channels. Calibration stability is within 0.5 K for all channels, also well within the 2 K requirement. TEMPEST-D has NEDTs similar to or lower than MHS. Therefore, although the TEMPEST-D radiometer is substantially smaller, lower power, and lower cost than operational radiometers, it has comparable performance, i.e. instrument noise, calibration accuracy and calibration stability.

How to cite: Reising, S. C., Berg, W., Brown, S. T., Gaier, T. C., Kummerow, C. D., Chandrasekar, V., Padmanabhan, S., Lim, B. H., Schulte, R., Goncharenko, Y., and Radhakrishnan, C.: Calibration and Validation of Microwave Atmospheric Sounders on CubeSats and Small Satellites for Applications in Weather Prediction and Climate Monitoring, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21378, https://doi.org/10.5194/egusphere-egu2020-21378, 2020.

EGU2020-20026 | Displays | GI3.4

The Global Environmental Monitoring Systems (GEMS) Constellation of Passive Microwave Satellite

Gregory Porter, Richard Delf, Albin Gasiewski, Michael Hurowitz, David Gallaher, Brian Sanders, William Hosack, David Kraft, Roger Carter, Kun Zhang, and Geoffrey Sasaki

The recent successful launch of the Orbital Micro Systems GEMS-1 IOD (Global Environmental Monitoring System In-orbit Demonstrator) satellite carrying the University of Colorado’s MiniRad 118-GHz imager/sounder instrument provides the basis for a new means of observing atmospheric precipitation, temperature, and related state variables. GEMS-1 supports an 8-channel passive microwave radiometer operating at the 118.7503 GHz oxygen resonance with cross-track scanning imaging system providing cross- and along track Nyquist sampling at 17 km 3dB spatial resolution. It is precisely calibrated using cold space views along with and an on board reference, yielding the first low-cost commercial weather satellite imagery. GEMS is the first of a constellation of approximately 50 such satellites of progressively improving resolution and spectral coverage that will collectively provide Nyquist time-sampling of precipitation and related weather variables on a global basis, and using microwave frequencies will provide such information probing through most cloud cover. Presented will be first light imagery and on-orbit performance data from the GEMS-1 mission, including validation data on the satellite brightness temperatures. Products will include calibrated multispectral imagery, temperature profiles, retrieved rain rate, and precipitation cell top altitude. The expansion of the GEMS-1 mission to the full GEMS constellation will be outlined.

How to cite: Porter, G., Delf, R., Gasiewski, A., Hurowitz, M., Gallaher, D., Sanders, B., Hosack, W., Kraft, D., Carter, R., Zhang, K., and Sasaki, G.: The Global Environmental Monitoring Systems (GEMS) Constellation of Passive Microwave Satellite, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20026, https://doi.org/10.5194/egusphere-egu2020-20026, 2020.

EGU2020-7124 | Displays | GI3.4

3D forest model-assisted validation of the Sentinel-2 SNAP fAPAR product

Niall Origo, Joanne Nightingale, Kim Calders, and Mathias Disney

fAPAR is a radiometric quantity describing the fraction of photosynthetically active radiation (PAR) absorbed by a plant canopy. It is an important component of carbon cycle and energy balance models and has been named as one of the 50 Global Climate Observing System (GCOS) essential climate variables (ECVs). Space agencies such as the ESA and NASA produce satellite fAPAR products in order to address the need for spatially explicit global data to address environmental and climate change issues. Given the derived nature of satellite fAPAR products it is essential to independently verify the results they produce. In order to do this, validation sites (or networks of sites) are needed that directly correspond to the measurands. Further to this, in order to understand divergences between product and validation data, uncertainty information should be provided with all measurement results.

The canopy radiative transfer models which are used in satellite-derived fAPAR products implement simplistic assumptions about the state of the plant canopy and illumination conditions in order to retrieve an fAPAR estimate in a computationally feasible time. This contribution assesses the impact of the assumptions made by the Sentinel-2 SNAP-derived fAPAR and includes it in a validation of the product over a field site (Wytham Woods, UK), which also has concurrent fAPAR measurements. This is achieved using a 3D model of Wytham Woods which is used to simulate biases associated with specific assumption types. These are used to convert the in situ measurements to the same quantity assumed by the satellite product. The measurement network which provides the fAPAR data is also traceable to SI through sensor calibrations and has associated uncertainty estimates. To our knowledge, these latter points have not been implemented in the biophysical product validation literature, which may explain some of the large discrepancies seen between validation and satellite-derived fAPAR data.

The ultimate aim of this work is to demonstrate a validation framework for derived biophysical variables such as fAPAR which properly considers the quantity estimated by the satellite and that measured by the in situ sensors, whilst providing metrologically derived uncertainties on the in situ data. This will help to properly inform users as to the quality of the data and determine whether the GCOS requirements set for fAPAR are attainable, ultimately improving carbon cycle and energy balance estimates.

How to cite: Origo, N., Nightingale, J., Calders, K., and Disney, M.: 3D forest model-assisted validation of the Sentinel-2 SNAP fAPAR product, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7124, https://doi.org/10.5194/egusphere-egu2020-7124, 2020.

EGU2020-11996 | Displays | GI3.4

Evaluation of globally gridded SST products from NOAA, CMC and UKMeto using AIRS and CrIS SST measurements.

Hartmut Aumann, Evan Manning, Chris Wilson, and Jorge Vasquez

The Sea Surface Temperature (SST) is a key component of climate research and daily globally gridded SST products are a key input to this effort.  Here we evaluate the NOAA RTGSST, which goes back to 1996, the Canada Meteorological Center (CMC) SST, available since 2002, and the OSTIA SST by the UK MetOffice, available since 2012. The calibration of the three products is tied to the moored and floating buoys along the equator, but there are differences in the way all grid points are optimally filled. The 2016 annual mean between 30S and 30N, 299.7K, differed by only 8 mK. However zonal mean differences between the three products north of 30N and south of 30S latitude are  of the order of 150 mK, and of opposite signs. Even more puzzling is that during 2016 the CMC was on average 150 mK colder than the OSTIA at 280K, while being warmer by 150mK at 290K. Differences of this magnitude are of concern when measure warming of the oceans at the rate of 15 mK/year. We use the daily mean and standard deviation and trends of the difference between the SST measured with AIRS (Atmospheric Infrared Sounder) since 2002 and CrIS (Crosstrack Interferometer Sounder) since 2012 to evaluate the three products.         

How to cite: Aumann, H., Manning, E., Wilson, C., and Vasquez, J.: Evaluation of globally gridded SST products from NOAA, CMC and UKMeto using AIRS and CrIS SST measurements., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11996, https://doi.org/10.5194/egusphere-egu2020-11996, 2020.

EGU2020-21846 | Displays | GI3.4

Airborne mapping and in situ validation of European land surface temperature using the NASA-JPL HyTES sensor. Results from the 2019 European NET-Sense Campaign in support of the Copernicus High Priority Candidate satellite mission development.

Martin Wooster, James Johnson, Tom Dowling, Mark de Jong, Mark Grosvenor, Mary Langsdale, Simon Hook, Bjorn Eng, William Johnson, Gerardo Rivera, Glynn Hulley, Dirk Schüttemeyer, and Benjamin Koetz

The NASA ESA Temperature Sensing Experiment (NET-Sense) is a NASA and ESA funded campaign in support of the Copernicus Land Surface Temperature Monitoring (LSTM) satellite mission.

The LSTM mission would carry a calibrated, high spatial-temporal resolution thermal infrared imager whose data would be used to provide the land-surface temperature information required for such applications as evapotranspiration estimation at the European field-scale. The LSTM mission responds to priority requirements of the agricultural user community for improving sustainable agricultural productivity in a world of increasing water scarcity and variability.

As part of the effort to LSTM mission development effort, the first non-US flights of NASA JPL’s state-of-the-art Hyperspectral Thermal Emission Spectrometer (HyTES) were conducted on a UK research aircraft in both the UK and Italy in June and July 2019. HyTES is an airborne thermal hyperspectral imager providing extremely high quality and radiometrically precise infrared radiances within 256 spectral channels across the spectral range 7.5 to 12 µm, with the primary aim to map LST and surface spectral emissivity. Flights in Italy were accompanied by the HyPLANT and TASI instruments, operated by FZ-Juelich, Germany installed aboard a second aircraft from CzechGlobe (CZ).

We provide an overview of the NET-Sense campaign, example results from HyTES and comparisons to in situ LST and surface spectral emissivity data collected co-incident with the aircraft overflights using tower-mounted radiometers and portable FTIR spectrometers adapted for the purpose. We explain the integration of NET-Sense into the broader science strategy for the LSTM mission, and highlight planned activities for the coming years, including NET-Sense 2020 European campaign plans.

How to cite: Wooster, M., Johnson, J., Dowling, T., de Jong, M., Grosvenor, M., Langsdale, M., Hook, S., Eng, B., Johnson, W., Rivera, G., Hulley, G., Schüttemeyer, D., and Koetz, B.: Airborne mapping and in situ validation of European land surface temperature using the NASA-JPL HyTES sensor. Results from the 2019 European NET-Sense Campaign in support of the Copernicus High Priority Candidate satellite mission development., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21846, https://doi.org/10.5194/egusphere-egu2020-21846, 2020.

EGU2020-1683 | Displays | GI3.4

Validation of NASA, NOAA AND ESA mid and thermal infrared data and products using the Lake Tahoe and Salton Sea automated validation sites

Simon Hook, Kerry Cawse-Nicholson, William Johnson, Robert Radocinski, and Gerardo Rivera

The stated goal of NASA’s Earth Science Research Program is to utilize global measurements to understand the Earth system and its interactions as steps toward the prediction of Earth system behavior. NASA has identified the provision of well-calibrated, multiyear and multi-satellite data and product series as a key requirement for meeting this goal. In order to help address this goal we have established two automated validation sites where the necessary measurements for validating mid and thermal infrared data from spaceborne and airborne sensors are made every few minutes on a continuous basis.
The two automated validation sites are located at Lake Tahoe CA/NV and Salton Sea CA. The Lake Tahoe site was established in 1999 and the Salton Sea site was established in 2008. Lake Tahoe is ideally suited for validation of mid and thermal infrared data for several reasons including its size, homogeneity, elevation, accessibility and composition. In order to use Lake Tahoe for validation, 4 buoys have been deployed. Each buoy includes a custom-built highly accurate (50mK) radiometer measuring the surface skin temperature and several bulk temperature probes that trail behind the buoy. Each buoy includes a logging system with dial-up cellular access and two full meteorological station measuring wind speed, wind direction, relative humidity and net radiation. All the measurements are made every few minutes and downloaded hourly via a cellular modem. The buoy measurements are supplemented with a variety of atmospheric measurements made on-shore. The Salton Sea site was established in 2008 to validate high water temperatures, up to 35 C and evaluate the performance of surface temperature retrieval algorithms under wet and dry atmospheres depending on time of year. 
Data from the sites have been used to validate numerous satellite instruments including the Advanced Very High Resolution Radiometer (AVHRR) series, the Along Track Scanning Radiometer (ATSR) series, the Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER), the Landsat series, the Moderate Resolution Imaging Spectroradiometer (MODIS) on both the Terra and Aqua platforms, the Visible Infrared Imaging Radiometer Suite (VIIRS) and the ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS). In all cases the standard products have been validated including the standard radiance at sensor, radiance at surface, surface temperature and surface emissivity products. We will present results from the validation of the mid and thermal infrared data from several of the aforementioned instruments and cross compare those results.

© 2020 California Institute of Technology. Government sponsorship acknowledged.

How to cite: Hook, S., Cawse-Nicholson, K., Johnson, W., Radocinski, R., and Rivera, G.: Validation of NASA, NOAA AND ESA mid and thermal infrared data and products using the Lake Tahoe and Salton Sea automated validation sites, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1683, https://doi.org/10.5194/egusphere-egu2020-1683, 2020.

The Radiometric Calibration Test Site (RadCaTS) was developed by the University of Arizona to provide satellite operators and the scientific community with daily ground-based data that are appropriate for the radiometric calibration and surface reflectance product validation of Earth-observation sensors. It is located at Railroad Valley, Nevada, USA, which has been used by the University of Arizona since 1996. The primary goal of RadCaTS is to provide data that can be used for the independent, accurate, and timely analysis of both the radiometric calibration and surface reflectance validation of Earth-observation sensors that operate in the solar-reflective region (400 nm to 2500 nm). RadCaTS is currently being used to monitor low-Earth orbit sensors such as Terra and Aqua MODIS, SNPP and NOAA-20 VIIRS, Landsat 8 OLI, Sentinel-2A and -2B MSI, Sentinel-3A and -3B OLCI and SLSTR, as well as geosynchronous sensors such as GOES-16 and ‑17 ABI. RadCaTS is currently one of four automated test sites that make up the CEOS WGCV IVOS Radiometric Calibration Network (RadCalNet), which seeks to harmonize the ground-based calibration and validation measurements from international organizations. This work presents current results from RadCaTS, as well as a comparison with results obtained from the RadCalNet data portal, which became publicly available at no cost to registered users in June 2018.

How to cite: Czapla-Myers, J. and Anderson, N.: Calibration and Validation of Earth-Observing Sensors Using The Radiometric Calibration Test Site (RadCaTS) at Railroad Valley, Nevada, USA, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20557, https://doi.org/10.5194/egusphere-egu2020-20557, 2020.

Surface albedo is a fundamental radiative parameter which controls the Earth’s energy budget by determining the amount of solar radiation which is either absorbed by the surface or reflected back to atmosphere. Satellite observations have long been used to capture the temporal and spatial variations of surface albedo because of their repeated global coverage. In this work, a new method of upscaling surface albedo from ground level footprints of a few tens of metres to coarse satellite scales (≈1km) is reported [1]. Tower-mounted albedometer measurements are upscaled and used to validate global space-based albedo products, including Copernicus Global Land Service (CGLS) 1km albedo data (from Proba-V and previously form VEGETATION-2), MODerate resolution Imaging Spectroradiometer (MODIS) 500m albedo data, and Multi-angle Imaging SpectroRadiometer (MISR) 1.1km albedo data. MODIS albedo retrievals show the closest agreement with tower measurements, followed by the MISR retrievals, and then followed by the CGLS retrievals. The upscaling method uses high-resolution surface reflectance retrievals (from Landsat-8, Sentinel-2) to fill the spatial gaps between the albedometer’s field-of-view (FoV) and coarse satellite scales. High-resolution surface albedo products are generated by combining high-resolution surface reflectance data and MODIS bi-directional reflectance distribution function (BRDF) climatology data. This upscaling framework also uses a novel Sensor Invariant Atmospheric Correction (SIAC) method [2] to improve the accuracy of upscaled tower albedo values. Total uncertainties of upscaled albedo products are estimated by considering uncertainties from both the tower albedometer raw measurements and SIAC atmospheric corrections. This surface albedo upscaling method can be used over both heterogenous and homogenous land surfaces, and has been examined at the SURFRAD, BSRN and FLUXNET tower sites.

Keywords: surface albedo, upscale, CGLS, MODIS, MISR, SIAC

[1] Song, R.; Muller, J.-P.; Kharbouche, S.; Woodgate, W. Intercomparison of Surface Albedo Retrievals from MISR, MODIS, CGLS Using Tower and Upscaled Tower Measurements. Remote Sens. 2019, 11, 644, doi:10.3390/rs11060644.

[2] Yin, F., Lewis, P. E., Gomez-Dans, J., & Wu, Q. A sensor-invariant atmospheric correction method: application to Sentinel-2/MSI and Landsat 8/OLI. EarthArXiv 2019, https://doi.org/10.31223/osf.io/ps957.

How to cite: Song, R. and Muller, J.-P.: Operational Validation of Space-based Albedo Products from Upscaled Tower-based Albedometer Measurements, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2731, https://doi.org/10.5194/egusphere-egu2020-2731, 2020.

EGU2020-13850 | Displays | GI3.4

Operational satellite validation with data from the Pandonia Global Network (PGN)

Alexander Cede, Martin Tiefengraber, Angelika Dehn, Barry Lefer, Jonas von Bismarck, Stefano Casadio, Nader Abuhassan, Robert Swap, and Luke Valin

The Pandonia Global Network (PGN) is a worldwide operating network of passive remote sensing spectrometer systems named “Pandora”. PGN is measuring atmospheric trace gases at high temporal resolution with the purpose of air quality monitoring and satellite validation. PGN is an activity carried out jointly by NASA, through the Pandora project at Goddard Space Flight Center, and ESA, through the Austrian contractor LuftBlick, as part of their Joint Program Planning Group Subgroup on calibration and validation and field activities. Many of the more than 50 actual PGN instruments are directly owned by NASA or ESA, another part belongs to other collaborating governmental and academic institutions. A major objective of the PGN is to support the validation and verification of more than a dozen low-earth orbit and geostationary orbit based UV-visible sensors, most notably Sentinel 5P, TEMPO, GEMS and Sentinel 4. PGN instruments are homogeneously calibrated and their data are centrally processed in real-time. Starting in June 2019, the PGN team has made more and more network locations “official PGN sites”, which means all required technical and logistical steps for this purpose have been performed. At the end of 2019 there are 18 such official network sites, where quality assured data are uploaded daily to EVDC (ESA Atmospheric Validation Data Centre), where they are used for operational validation of Sentinel 5P retrievals (see e.g. http://mpc-vdaf-server.tropomi.eu/no2/no2-offl-pandora). The current official PGN data products are total vertical column amounts of NO2 and O3 from direct sun observations. Research data products include total vertical columns amounts of SO2 and HCHO from direct sun observations as well as surface concentrations, tropospheric columns amounts, and vertical profiles for NO2 and HCHO from sky observations. These named research products are planned to become official over the course of the year 2020.

How to cite: Cede, A., Tiefengraber, M., Dehn, A., Lefer, B., von Bismarck, J., Casadio, S., Abuhassan, N., Swap, R., and Valin, L.: Operational satellite validation with data from the Pandonia Global Network (PGN), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13850, https://doi.org/10.5194/egusphere-egu2020-13850, 2020.

EGU2020-22245 | Displays | GI3.4

The Earthnet Data Assessment Pilot Project: Paving the Way for New Space Players

Samuel Hunt, Nigel Fox, Kevin Halsall, Andrea Melchiorre, Sébastien Saunier, Alessandro Piro, Davide Giudici, Clément Albinet, Valentina Boccia, and Philippe Goryl

In recent years, the increasing range of applications of Earth Observation data products and availability of low-cost satellites has resulted in an increasing number of commercial satellite systems. These services may provide complementary capabilities to those of Space Agencies.  Adoption of these data products for many applications requires that they meet an assured level of quality that is fit for the given purpose.  For the most efficient exploitation of EO data,  therefore,  assessment of data quality, calibration and validation are indispensable tasks,  forming  the basis for reliable scientific conclusions.  

 

In this context, the European Space  Agency has established the Earthnet  Data Assessment Pilot  (EDAP) project, which aims to enable maximum exploitation of growing data availability by performing early data assessment for various missions that fall into one of the following instrument domains number of  missions, in the Optical, SAR and atmospheric  domains. These assessments are intended to evaluate and report the quality of a satellite mission with respect to what is “fit for purpose” within the context of the its stated performance and application. This activity compliments similar activities from other international partners, including NASA. 

 

Such quality information is often  communicated to users  in an ill-defined or incomplete manner.  We show the development of a generic satellite mission quality assessment framework, developed within EDAP, which is designed  provide a  thorough  review  of  all important  aspects of  mission quality. The assessment results are  conveye d ata top  level  to the user  as a quality assessment matrix diagram. The framework  itself  is based on  the principles of CEOS QA4EO (Quality Assurance for Earth Observation)  and  builds  on the experience  of  several  European projects that worked towards  practically  implementing them. 

 

In a wider context,  such a  framework has  potential for  more general use  in both institutional and commercial Earth Observation  –  helping  mission providers  to understand  the  information their  users  need and  empowering  users  to make informed decisions about which data is fit for their purpose.  As such, there is potential for international collaboration, between space agencies, to synergise quality assessment approaches and to work towards the development of a common standard.

How to cite: Hunt, S., Fox, N., Halsall, K., Melchiorre, A., Saunier, S., Piro, A., Giudici, D., Albinet, C., Boccia, V., and Goryl, P.: The Earthnet Data Assessment Pilot Project: Paving the Way for New Space Players, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22245, https://doi.org/10.5194/egusphere-egu2020-22245, 2020.

EGU2020-10856 | Displays | GI3.4

Inter-Calibration of nine UV sensing instruments over Antarctica and Greenland since 1980: impact on global UV cloud albedo trends

Clark Weaver, Gordon Labow, Dong Wu, Pawan K. Bhartia, and David Haffner

A suite of NASA/NOAA UV (340nm) sensing satellite instruments, starting with Nimbus-7 SBUV in 1980, provides a global long-term record of cloud trends and cloud response from ENSO events. We present new method to inter-calibrate the radiances of all the SBUV instruments and the Suomi NPP OMPS mapper over both the East Antarctic Plateau and Greenland ice sheets during summer. First, the strong solar zenith angle dependence from the intensities are removed using an empirical approach rather than a radiative transfer model. Then small multiplicative adjustments are made to these solar zenith angle normalized intensities in order to minimize differences when two or more instruments temporally overlap. While the calibrated intensities show a negligible long-term trend over Antarctica, and a statistically insignificant UV albedo trend of -0.05 % per decade over the interior of Greenland, there are small episodic reductions in intensities which are often seen by multiple instruments. Three of these darkening events are explained by boreal forest fires using trajectory modeling analysis. Other events are caused by surface melting or volcanoes. We estimate a 2-sigma uncertainty of 0.35% for the calibrated radiances. Finally, we connect the estimated radiance uncertainties, derived from our calibration approach, to the tropical and midlatitude UV cloud albedo trends.

How to cite: Weaver, C., Labow, G., Wu, D., Bhartia, P. K., and Haffner, D.: Inter-Calibration of nine UV sensing instruments over Antarctica and Greenland since 1980: impact on global UV cloud albedo trends, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10856, https://doi.org/10.5194/egusphere-egu2020-10856, 2020.

NASA’s Earth Radiation Budget Science Team, ERB-ST, (Previously known as the CERES Science Team) is a multi-disciplinary team led out of NASA’s Langley Research Center which has the responsibility for governance of the nation’s multi-decadal Earth Radiation Budget Climate Data Record, ERB CDR.  The Science Data Processing System which produces the ERB-CDR is highly complex, producing Level one through Level 4 products.  The system ingests data from 15 different instruments on 9 different spacecraft (5 GEO and 4 LEO) as well as other ancillary information, producing 25 different products with consistent TOA, Surface, and atmospheric radiative fluxes, cloud and aerosol properties on multiple spatial and temporal scales.  Spatial scales vary from instantaneous/pixel (25 km), 1-deg grid, zonal, regional and global means while temporal scales vary across instantaneous, hourly, 3 hourly to monthly scales.  Accuracy and precision values vary across the various spatial and temporal scales, with the long-term goal of measuring decadal trends of better than 0.3 W/m^2 per decade.

 

Instrument calibration and precision, as measured through the post-launch protocols, is one of many considerations that drive the decision to reprocess, others include, but are not limited to validation and instantiation of new algorithms across all levels of products, outside teams reprocessing the products we ingest, the launch of new instrumentation to replace operational weather imagers on Geo satellites, updates to processing hardware, and of course resource availability.  These all need to be managed/considered in order to provide the global community products of sufficient accuracy and precision on a time-scale which allows continued advancement and discovery of key scientific questions such that policy makers may make informed decisions.

 

This presentation will highlight the processes and protocols the Earth Radiation Budget Science Team utilizes to guide reprocessing decisions, identifying lessons learned and best practices.

How to cite: Priestley, K., Shankar, M., and Thomas, S.: Generation of a multi-decadal Earth Radiation Budget Thematic Climate Data Record : Balancing accuracy, precision, and availability to meet the needs of the community, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22221, https://doi.org/10.5194/egusphere-egu2020-22221, 2020.

EGU2020-3754 | Displays | GI3.4

A New Highly Stable Multi-Decade Satellite Climate Data Set Derived from Polar Hyperspectral Infrared Sensors

Chris Hepplewhite, Larrabee Strow, Howard Motteler, Sergio de Souza-Machad, and Steven Buczkowski

NASA's Atmospheric Infrared Sounder (AIRS) started the continuous measurement of the Earth's upwelling infrared radiation at high spectral resolution in Sept. 2002 in a 13:30 polar orbit.  The AIRS record was supplemented by the CrIS sensor flying on the NASA SNPP platform, also in the 13:30 polar orbit, in 2012.  In 2018 a second CrIS sensor on NOAA's JPSS-1 platform (NOAA-20) began operation, also in the 13:30 orbit.  Two more CrIS sensors are presently being procured for the JPSS-2 and 3 satellites, which will extend this record from 2002 through ~2040.  EUMETSAT's METOP-A/B/C provide very similar hyperspectral observations starting with the IASI sensors in the 09:30 orbit, starting in 2007, which will be continued with METOP-SG for years to come.  

Inter-calibration of all of the operating sensors shows agreement generally to 0.2K or better in brightness temperature.  More importantly, we have shown that the radiometric stability of the AIRS sensors is in the 0.002 K/year range or 0.02K/decade, based on measurements of CO2 and SST trends.   Similar stability is expected for CrIS and IASI.  Community consensus suggests that direct radiance trending, followed by conversion of these trends to geophysical quantities will yield the most accurate climate trends.  

Here we introduce a new satellite hyperspectral infrared radiance product we call the "Climate Hyperspectral InfraRed Product (CHIRP)" that combines AIRS, CrIS, and IASI into a homogeneous Level 1 radiance product with a common spectral response and channel centers for all three satellites.  This grid is equivalent to an interferometer with optical path differences of 0.8/0.6/0.4 cm for the long-wave/mid-wave/short-wave spectral bands.  This corresponds to a virtual instrument with the same spectral resolution of the JPSS-1 CrIS sensor in the long-wave, with 25/50% degradation in spectral resolution in the mid-wave/short-wave.  This choice allows accurate conversion of the long AIRS record to an equivalent interferometer record.  Conversion of IASI to CHIRP is trivial.  Conversion of all sensors to the CHIRP spectra grid permits simple adjustments of inter-satellite radiometric bias differences since all measurements are first converted to a common spectral grid.  Multiple methods (SNOs, statistical inter-comparisons) indicate these adjustments can be made to the 0.03K level or better.   

A sample application of CHIRP to climate trending will be given by showing multi-decade anomalies of temperature, humidity, and ozone profiles retrieved from CHIRP radiance anomalies, a retrieval that requires almost no a-priori information.  This data set should yield definitive measurements of water-vapor feedback and heavily contribute to our understanding of both tropospheric and stratospheric temperature trends.   Initial production of CHIRP radiances that combine AIRS and CrIS are expected to begin in late 2020.  

How to cite: Hepplewhite, C., Strow, L., Motteler, H., de Souza-Machad, S., and Buczkowski, S.: A New Highly Stable Multi-Decade Satellite Climate Data Set Derived from Polar Hyperspectral Infrared Sensors, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3754, https://doi.org/10.5194/egusphere-egu2020-3754, 2020.

Meteorological satellites have become an irreplaceable weather and ocean-observing tool in China. These satellites are used to monitor natural disasters and improve the efficiency of many sectors of Chinese national economy. It is impossible to ignore the space-derived data in the fields of meteorology, hydrology, and agriculture, as well as disaster monitoring in China, a large agricultural country. For this reason, China is making a sustained effort to build and enhance its meteorological observing system and application system. The first Chinese polar-orbiting weather satellite was launched in 1988. Since then China has launched 17 meteorological satellites, 8 of which are sun synchronous and 9 of which are geostationary satellites; China will continue its two types of meteorological satellite programs.

In order to achieve the in-orbit absolute radiometric calibration of the operational meteorological satellites’ thermal infrared channels, China radiometric calibration sites (CRCS) established a set of in-orbit field absolute radiometric calibration methods (FCM) for thermal infrared channels (TIR) and the uncertainty of this method was evaluated and analyzed based on TERRA/AQUA MODIS observations. Comparisons between the MODIS at pupil brightness temperatures (BTs) and the simulated BTs at the top of atmosphere using radiative transfer model (RTM) based on field measurements showed that the accuracy of the current in-orbit field absolute radiometric calibration methods was better than 1.00K (@300K, K=1) in thermal infrared channels. Therefore, the current CRCS field calibration method for TIR channels applied to Chinese metrological satellites was with favorable calibration accuracy: for 10.5-11.5µm channel was better than 0.75K (@300K, K=1) and for 11.5-12.5µm channel was better than 0.85K (@300K, K=1).

How to cite: Zhang, Y., Rong, Z., and Hao, X.: Uncertainty Evaluations of the CRCS In-orbit Field Radiometric Calibration Methods for Thermal Infrared Channels of FENGYUN Meteorological Satellites, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5563, https://doi.org/10.5194/egusphere-egu2020-5563, 2020.

EGU2020-5818 | Displays | GI3.4

A Unique Airborne Multi-angular Dataset for Calibration and Validation of Earth Satellite Products

Charles Gatebe, Rajesh Poudyal, and Michael King

The Cloud Absorption Radiometer (CAR) Science Team, and the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) recently released a unique dataset of bidirectional reflectance-distribution function (BRDF) of different surface types including clouds, snow/ice, vegetation, ocean, lakes, desert, city scape, smoke and other mixed surface types. The data were acquired during numerous field campaigns around the world, with measurements spanning 1991 to 2017. This presentation will address several uses of these data including developing new methods that define important surface and atmosphere radiative transfer functions, improve remote sensing retrievals of multiple geophysical parameters such as aerosols, clouds and surface albedo, and support satellite remote sensing activities.  CAR data are archived at GES DISC:  https://disc.gsfc.nasa.gov/datasets?keywords=car.

How to cite: Gatebe, C., Poudyal, R., and King, M.: A Unique Airborne Multi-angular Dataset for Calibration and Validation of Earth Satellite Products, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5818, https://doi.org/10.5194/egusphere-egu2020-5818, 2020.

EGU2020-7097 | Displays | GI3.4

Monitoring and performances evolutions of the 3 in-flight IASI instruments on-board METOP satellites

Laura Le Barbier, Mathilde Faillot, Elsa Jacquette, Laurence Buffet, Antoine Penquer, Olivier Vandermarcq, Bernard Tournier, Yannick Kanghah, Denis Jouglet, Anais Vincensini, Silvia Enache, Jean-Christophe Calvel, Fy Andrianony, and Tristan Lalanne

The EUMETSAT Polar System (EPS) programme is composed of three polar orbiting meteorological METOP satellites. The main payload instrument on-board each METOP is an InfraRed Atmospheric Sounding Interferometer (IASI). METOP-A, the first one of this series, was launched in 2006. Then METOP-B and METOP-C were launched successively in 2012 and 2018. IASI instrument products are disseminated to meteorological institutions for numerical weather prediction, to laboratories for atmospheric and climate studies and also to space agencies for expertise and monitoring. Since their beginning of life, IASI on-board METOP-A and METOP-B continue to perform very well and therefore demonstrate IASI instrument great performances stability and its sturdiness over time. Since July 2019, IASI on-board METOP-C is operational. It will ensure the continuity of good calibrated data dissemination to the user community for the next decade.

The purpose of this paper is to present the current performances status of the 3 in-flight IASI instruments, up to the Level 1 data. The objective is to give a feedback on the validation and the monitoring performed on IASI instruments during its life time. Moreover, during the past few years, some operational improvements were applied like the update of the on-board non-linerity correction for the 3 instruments. The impact of this new correction will be presented, also the reprocessing of a huge amount of IASI-A data for climate series.

New improvements will be assessed, like the impact on the spectral calibration monitoring of the new release of the GEISA spectroscopic database and the 4A/OP atlases or improvements of inter-comparison techniques.

How to cite: Le Barbier, L., Faillot, M., Jacquette, E., Buffet, L., Penquer, A., Vandermarcq, O., Tournier, B., Kanghah, Y., Jouglet, D., Vincensini, A., Enache, S., Calvel, J.-C., Andrianony, F., and Lalanne, T.: Monitoring and performances evolutions of the 3 in-flight IASI instruments on-board METOP satellites, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7097, https://doi.org/10.5194/egusphere-egu2020-7097, 2020.

EGU2020-11268 | Displays | GI3.4

Evaluation of calibrations for limb scattering sensors

Natalya Kramarova, Pawan Bhartia, Glen Jaross, and Zhong Chen

The Ozone Mapping and Profiler Suite represents a new generation of the US ozone measuring instruments aimed to monitor the ozone recovery associated to the reduction in levels of man-made ozone depleting substances regulated by the Montreal protocol. The first OMPS was launched on board of the Suomi NPP satellite in October 2011. The Limb Profiler is a part of the OMPS instrumental suite, and it collects solar radiances scattered from the atmospheric limb in the UV and VIS spectral ranges. The next OMPS Limb Profiler is scheduled to launch in 2022 on board of NASA/NOAA JPSS-2 mission. These limb scattering measurements allow to retrieve vertical ozone profiles from the tropopause up to the mesosphere with a high vertical resolution (~2 km). The expected ozone recovery is almost three times slower than the ozone loss observed in 1980s and 1990s. To detect such small trends in ozone concentration, the instrument calibrations should be extremely accurate. Comparisons of ozone retrievals from OMPS LP with the correlative satellite measurements from Aura MLS and ISS SAGE III revealed that OMPS LP retrievals accurately characterize the vertical ozone distribution in different atmospheric regions which are most sensitive to changes in the stratospheric composition and dynamics. Between 18 and 42 km the mean differences between LP and correlative measurements are within ±10%, except for the northern high latitudes where between 20 and 32 km biases exceed 10% due to the measurement errors. We also found a small positive drift of ~0.5%/yr against MLS with a pattern that is consistent with the ~150-meter drift (over 7 years) in sensor pointing detected by one of our altitude resolving methods. The spatial patterns in the ozone biases and drifts suggest that remaining errors in the LP ozone retrievals are due to errors in altitude registration and instrument calibrations. We present a study where we evaluate calibrations of the OMPS LP by converting ozone differences between OMPS LP and Aura MLS into differences in radiances. Then these radiance differences are compared with the LP measured radiances to determine errors in OMPS LP calibrations. Since the OMPS LP has three slits, some of the errors, like a drift in the altitude registration, should be common across all three slits, but other errors will be unique for each slit, helping to isolate different sources of errors. This approach can be extended to earlier ESA’s limb scattering missions, like SCIAMACHY and OSIRIS, since MLS has long overlap with the ENVISAT and Odin missions.

How to cite: Kramarova, N., Bhartia, P., Jaross, G., and Chen, Z.: Evaluation of calibrations for limb scattering sensors, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11268, https://doi.org/10.5194/egusphere-egu2020-11268, 2020.

EGU2020-11607 | Displays | GI3.4

The use of radiative transfer modeling to compare normalized radiances from different instruments

Colin Seftor, Glen Jaross, Leslie Moy, Natalya Kramarova, and Eun-su Yang

Measured sun-normalized radiances (S-NRs) from both the Ozone Mapping and Profiler Suite (OMPS) Nadir Mapper (NM) and Nadir Profiler (NP) on the Suomi National Polar-orbiting Partnership (SNPP) satellite have been validated to the 2% level through, in part, comparisons with radiative transfer code calculations using co-located ozone profile retrievals inputs from the Microwave Limb Sounder (MLS) on the Aura satellite. To minimize the effects of clouds and aerosols, only low reflectivity and low aerosol scenes were used. We will describe the details of the comparison technique, including how low reflectivity / low aerosol scenes were determined.  We will also show results where we extend our study to compare measured S-NRs from the OMPS nadir sensors with those from both the Ozone Monitoring Instrument (OMI) on Aura sensor and, if available, the Version 2 dataset from the TROPOMI sensor on the Sentinel 5 Precursor (S5P) satellite.

How to cite: Seftor, C., Jaross, G., Moy, L., Kramarova, N., and Yang, E.: The use of radiative transfer modeling to compare normalized radiances from different instruments, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11607, https://doi.org/10.5194/egusphere-egu2020-11607, 2020.

EGU2020-11922 | Displays | GI3.4

Does optimal estimation perform adequately for hyperspectral surface reflectance retrieval?

Jouni Susiluoto, Michael Turmon, Nimrod Carmon, and David Thompson

The current and coming imaging spectroscopy missions (EMIT, ECOSTRESS, AVIRIS-NG), and observables for potential future missions studying Surface Biology and Geology (SBG) observe a wide range of spectral bands, which can be used to infer about surface properties. The current state of the art approach for performing the retrieval of surface reflectance is optimal estimation (OE), which amounts to finding the maximum a posteriori estimate of the surface reflectance, after which the posterior covariance is approximated by linearizing the forward model (Rodgers, 2001). While this method has a principled basis and often performs well, with challenging atmospheres the optimization may fall into local minima, or the estimated posterior mean and covariance may be wrong.  Addressing these failures under realistic observing conditions is particularly important to realize the full potential of upcoming global observations.                                                                                                                                                                        


As a preparation to improving the quality of future retrievals, we evaluate the performance of OE against posteriors generated with advanced Bayesian techniques.  We present results from comparing the OE posterior mean and covariance to the true posterior, as computed by MCMC, for moderately challenging atmospheric conditions, and an instrument configuration consistent with AVIRIS-NG. 

How to cite: Susiluoto, J., Turmon, M., Carmon, N., and Thompson, D.: Does optimal estimation perform adequately for hyperspectral surface reflectance retrieval? , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11922, https://doi.org/10.5194/egusphere-egu2020-11922, 2020.

To meet the increasing demand for obtaining reliable information on the atmospheric distribution of trace gases and aerosols, GEO-constellation consisting of Geostationary Korean Multi-Purpose Satellite-2B (GK-2B), Tropospheric Emissions: Monitoring Pollution and Sentinel-4 are planned to be operated in this decade. As one of the environmental instruments, Geostationary Environment Monitoring Spectrometer (GEMS) onboard GK-2B planned to launch in February 2020 is designed to provide spectral radiance in the wavelength range of 300-500 nm as observing the tropical western Pacific region. To prepare a means of monitoring the calibration accuracy of GEMS, we aim to evaluate the feasibility of deep convective clouds (DCCs) as a possible target for vicarious calibration of GEMS. While the DCC calibration technique has been continuously verified from various meteorological satellite programs, it has been rarely researched in the ultraviolet and visible spectral region especially for the hyperspectral data of the environmental sensor. To finely detect DCCs reflecting stable signal throughout the spectral range of GEMS, we update the DCC detection thresholds based on the conventional detection method by applying both visible and infrared detection thresholds. To examine the effectiveness of the detection, Tropospheric Monitoring Instrument (TROPOMI) onboard Sentinel-5 Precursor is used as a proxy of GEMS. Advanced Himawari Imager onboard Himawari-8 is also used to construct the collocated data with TROPOMI since the environmental sensor only provides spectral radiance at shorter wavelengths. The DCCs detected by the updated thresholds show higher reflectivity over 0.9 as presenting homogeneous spectral features even at the Fraunhofer lines in which the atmospheric effects are prominent. Cloud properties such as the cloud optical thickness and cloud top height also become relatively homogeneous when both visible and infrared thresholds are used for the DCC detection since both radiation thresholds can be complement to limit the cloud properties of the detected clouds. With the detailed results, bidirectional reflectance distribution function (BRDF) is also to be estimated by applying the updated DCC detection method hereafter in the study.

How to cite: Lee, Y., Ahn, M.-H., and Kang, M.: Analysis on spectral reflectivity of deep convective clouds towards vicarious calibration of UV/VIS hyperspectral instruments onboard geostationary satellites, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18810, https://doi.org/10.5194/egusphere-egu2020-18810, 2020.

EGU2020-20067 | Displays | GI3.4

Inter-Calibrating Satellite Remote Sensors Using High Accuracy NASA CLARREO Pathfinder Instrument

Xu Liu, Wan Wu, Qiguang Yang, Yolanda Shea, Costy Lukashin, and Gary Fleming

NASA is planning to launch a highly accurate hyperspectral sensor to measure Earth-reflected solar radiances from the International Space Station in 2023.  The Climate Absolute Radiance and Refractivity Observatory (CLARREO) Pathfinder (CPF) instrument will have an absolute calibration accuracy of 0.3% (1-sigma), which is about a factor of 5 to 10 more accurate than current satellite reflected solar instruments.  We will describe the CPF approach developed to inter-calibrate the Clouds and Earth’s Radiant Energy System (CERES) and Visible Infrared Imaging Radiometer Suite (VIIRS) instruments.  A Principal Component-based Radiative Transfer Model (PCRTM) is used to perform high fidelity CPF radiance spectra simulation and to extend the spectral range of the CPF to match that of the shortwave CERES reflected solar radiation.  The PCRTM model can also be used to correct small errors due to imperfect angular matching between the CPF/CERES and CPF/VIIRS observation angles.  Examples of inter-calibration uncertainty that is anticipated will be demonstrated using simulated CPF data.

How to cite: Liu, X., Wu, W., Yang, Q., Shea, Y., Lukashin, C., and Fleming, G.: Inter-Calibrating Satellite Remote Sensors Using High Accuracy NASA CLARREO Pathfinder Instrument, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20067, https://doi.org/10.5194/egusphere-egu2020-20067, 2020.

EGU2020-20119 | Displays | GI3.4

Airborne Hyperspectral Trace Gas Sensors as Testbeds for Geostationary Air Quality Mission Validation

Scott Janz, Matthew Kowalewski, Lok Lamsal, Laura Judd, Caroline Nowlan, and Jassim Al-saadi

Next generation air quality sensors are currently planned to launch within the next couple of years. The Tropospheric Emissions: Monitory of Pollution (TEMPO-United States) and Geostationary Environment Monitoring Sensor (GEMS-South Korea) are two such missions that will probe the boundary layer/lower troposphere at unprecedented spatial and temporal scales. These missions are designed to provide constraints on chemical forecast models and specifically to answer the question: "What are the temporal and spatial variations of emissions of gases and aerosols important for air quality and climate?" In preparation for these missions a number of airborne air quality field missions have been performed to collect data at similar spatial and temporal scales, and during relevant seasonal air quality episodes including fires. This data is being used to improve the trace gas retrieval algorithms and explore the unique spatial scales and diurnal patterns that will be encountered when the geostationary experiments are operational. This overview will present details of two of the instruments used during these campaigns, the GeoCAPE Airborne Simulator (GCAS) and the Geostationary Trace Gas and Aerosol Sensor Optimization (GeoTASO) instruments. Maintained at the Goddard Space Flight Center's Radiometric Calibration and Development Facility (RCDF), these instruments are similar in design and sensitivty to what will be measured on-orbit by the TEMPO and GEMS sensors. Results of the retrieval of high spatial resolution nitrogen dioxide and formaldehyde will presented. Examples of vertical column retrievals will be presented under various source/weather conditions as well as the uncertainties that result from both instrument and radiative transfer assumptions.

How to cite: Janz, S., Kowalewski, M., Lamsal, L., Judd, L., Nowlan, C., and Al-saadi, J.: Airborne Hyperspectral Trace Gas Sensors as Testbeds for Geostationary Air Quality Mission Validation, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20119, https://doi.org/10.5194/egusphere-egu2020-20119, 2020.

EGU2020-20865 | Displays | GI3.4

Characterisation Campaign at the Gobabeb RadCalNet Site in Support of Satellite Calibration and Validation Activities

Morven Sinclair, Chris McLellan, Agnieszka Bialek, Emma R Woolliams, Sarah Taylor, and Nigel P Fox

With increasing use of satellite-derived data in climate and Earth monitoring, the importance of reliable and traceable radiometric and spectral information is key. Due to the difficulties of maintaining instrument calibration post-launch, vicarious calibration sites play a vital part in ensuring the stability and interoperability of satellite sensor data.

RadCalNet, the Radiometric Calibration Network established through the Committee on Earth Observation Satellites Working Group on Calibration and Validation (CEOS-WGCV), provides a network of, currently four, instrumented ground reference sites providing users with bottom and top-of-atmosphere (BOA and TOA) reflectance measurements every 30 minutes in 10 nm spectral intervals and for nadir view. (For all sites, more detailed spectral information and off-nadir reflectances can be obtained from site owners). It is a key aspect of RadCalNet that the sites document their traceability to the International System of Units (SI) and that they provide traceable uncertainties associated with individual observations. These documents and uncertainties are peer reviewed by the RadCalNet working group.  Each RadCalNet site provides ground reflectance observations that are propagated to TOA through a centralised processing system. RadCalNet has over 300 active users who value the available information.

Gobabeb, in Namibia, is one of these four sites, given the reference GONA. GONA was the first site that was established as a new RadCalNet site (the other sites were pre-existing) and the location was determined from a global survey to find suitable sites, primarily due to spatial uniformity and the probability of suitable atmospheric conditions, such as clear skies. With an automatic radiometric station, this site continuously collects atmospheric data and surface radiance measurements. These are then processed to ground spectral reflectance and provided with uncertainties to the RadCalNet processor which propagates values to TOA.

Due to the limitations of the instrument used for autonomous measurements, recent fieldwork has been carried out in this location to acquire additional hyperspectral data to maintain the quality of the site products. In addition, further site characterisation was conducted to prepare a best location for a new site nearby that is being developed under the HYPERNETS project. This paper presents both the RadCalNet site and the results of the recent fieldwork.

How to cite: Sinclair, M., McLellan, C., Bialek, A., Woolliams, E. R., Taylor, S., and Fox, N. P.: Characterisation Campaign at the Gobabeb RadCalNet Site in Support of Satellite Calibration and Validation Activities, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20865, https://doi.org/10.5194/egusphere-egu2020-20865, 2020.

EGU2020-21792 | Displays | GI3.4

Enabling and demonstrating SI traceability of ECVs and climate data records: the role of a national metrology institute

Nigel Fox, Paul Green, Joanne Nightingale, and Emma Woolliams

The need for SI traceability to ensure integrity and trust in the Essential Climate Variables (ECVs) and the services and information derived from them, is well established. However, the means to achieve and demonstrate this in a universally-consistent manner globally and between variables, particularly for the complex bio-geophysical variables that make up many of the ECVs, is challenging.

 

National Physical Laboratory (NPL), the UK national metrology institute, has, over the last three decades, established a comprehensive research programme to extend traditional underpinning laboratory-based capabilities to meet the needs of a wide range of Earth Observation and climate applications. These have included:

  • both bespoke and tailored standards together with methods for the calibration of remote-sensing instruments (including pre-flight calibration of satellite sensors),
  • field measurements in the worlds Forests, Oceans, Deserts and the atmosphere
  • development of metrological methods to assess and describe uncertainties, end to end (sensor to user-relevant information)
  • most recently, extending to the development of a satellite to establish SI traceability from orbit as part of the ESA EarthWatch programme.

 

To build the necessary skills, capacity and trust within the community, NPL has established a close dialogue with EO/climate community experts and built international partnerships through active participation in international bodies such as CEOS & GEO. This has led to a close working relationship with ESA and other European national and international space agencies to provide metrological support across a wide range of projects.

 

This paper will discuss the criticality of SI traceability to providing trust in globally-relevant environmental & climate datasets and illustrate how it is being achieved through case studies, such as:

  • the ESA Fiducial Reference Measurement (FRM) projects,
  • establishment of SI-traceable reference test-sites for satellite calibration and validation
  • novel infrastructure to calibrate and characterise optical satellite sensors
  • and efforts to harmonise their in-flight radiometric gain.

 

NPL plays a lead role in the recently created European Metrology Network for Climate and Ocean and is keen to continue to ensure its efforts and research program address the priorities of the EO and climate community and will welcome input on future research directions.

How to cite: Fox, N., Green, P., Nightingale, J., and Woolliams, E.: Enabling and demonstrating SI traceability of ECVs and climate data records: the role of a national metrology institute, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21792, https://doi.org/10.5194/egusphere-egu2020-21792, 2020.

The development of the IASI-NG System, under responsibility of CNES, includes the development
and delivery of IASI-NG instruments (to be flown on the Metop-SG A Satellites serie, the
development of the Level 1 C Processor (L1C POP) as part of the EPS-SG ground segment, and the
development of a Technical Expertise Centre (IASTEC) in charge of the in-flight calibration,
validation and continuous performance monitoring.
The IASI-NG instrument represents a major technological gap compared to the IASI Fourier
transform spectrometer. In order to be able to deliver data with both a twice lower radiometrical
noise and a twice better spectral resolution, the IASI-NG interferometer design is based on the Mertz
principle and uses movable prisms to compensate the so-called self-apodization effects. This change
of instrumental concept and our ability to send together to the ground the real and imaginary part of
the spectra lead to major changes in the definition of the IASI-NG algorithms compare to the IASI
ones and generally to an increase in their complexity.
This paper presents the processing chains involved in the radiometric and spectral calibration of the
IASI-NG spectra. The overall scheme of calibration is shown and a focus is put on major evolutions
induced by the new IASI-NG instrumental concept. Logically, this new concept impacts mainly the
algorithms in charge of the instrumental spectral response function estimation (ISRF-EM). Indeed, in
order to preserve the IASI user-friendly approach and to deliver spectrally consistent data, the
instrumental spectral response function (ISRF) of the spectrometer is continuously estimated onground
and removed by the level 1 processing.
This estimation relies on both an instrumental model and observable parameters coming from five
metrology beams, a Fabry-Perot interferometer or absorption features in the atmospheric spectra. We
will describe the two main parts of this algorithmic chain dedicated to the estimation, on one part, of
the spectral shift and on the other part, of the shape of the ISRF. The correction of these two effects is
done simultaneously in the on-ground processing by local deconvolution. The estimated ISRF is then
removed and replaced by a perfect Gaussian function. This correction is applied to each
interferogram and for each wavenumber because of the high chromatic effect (i.e. the variation of the
relative spectral shift with the wavenumber) due to the use of refractive optical components to create
opd.
A status will be made on the algorithms definition and the first end-to-end validation studies on the
whole processing chain conducted by the IASI-NG L1C team will be shown.

How to cite: Luitot, C.: IASI-NG L1 processing : new algorithms to calibrate a new instrument, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21871, https://doi.org/10.5194/egusphere-egu2020-21871, 2020.

EGU2020-22057 | Displays | GI3.4

Spectral Calibration of the SLSTR Focal Plane Assemblies

Tim Nightingale, Robert McPheat, Arrow Lee, Ed Polehampton, Ettore Pedretti, and Hugh Mortimer

We describe a novel technique – Fourier transform spectroscopy – that we have developed to characterise the spectral and polarisation responses of the Sentinel-3 SLSTR optical channels. Our method has a number of advantages over conventional approaches employing a grating monochromator, including excellent spectral registration and resolution, intrinsic rejection of self-emission from the test setup and fast measurement times. Our measurements are traceable, through the spectral responsivity of a reference detector and the wavelength of a HeNe laser, to national standards.

We illustrate our method with sample results from the spectral calibrations of the four SLSTR focal plane assemblies tested to date. 

How to cite: Nightingale, T., McPheat, R., Lee, A., Polehampton, E., Pedretti, E., and Mortimer, H.: Spectral Calibration of the SLSTR Focal Plane Assemblies, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22057, https://doi.org/10.5194/egusphere-egu2020-22057, 2020.

EGU2020-22345 | Displays | GI3.4

Validation of the EarthCARE Mission

Rob Koopman, Alain Lefebvre, Damien Maeusli, Tobias Wehr, Michael Eisinger, and Montserrat Piñol Solé

This poster will address the geophysical validation for EarthCARE. This mission is developed by the European Space Agency (ESA) in cooperation with the Japan Aerospace eXploration Agency (JAXA); both space agencies also agreed to define and coordinate a joint EarthCARE Validation programme. Beside providing the Cloud Profile Radar instrument and making available the related ground processing facilities, JAXA is as well responsible for the commissioning of the CPR, including the associated Validation Plan and activities. ESA will then integrate the CPR Validation Plan part into the joint EarthCARE Scientific Validation Implementation Plan. The two Agencies have already begun to consolidate this joint Scientific Validation Implementation Plan, and its overall status will be presented. The poster will then focus on the ESA-led Validation activities, in particular on validation of the Level 1 products of the ESA instruments (ATLID, BBR, MSI) and on the ESA-developed Level 2 products. These ESA Validation activities have been the outcome of an announcement of opportunity that was issued in 2017 and for which more than 30 proposals had been received. A broad peer review of this programme took place in 2018 during the 1st ESA Validation Workshop in Bonn (held in concomitance with the 7th EarthCARE Science Workshop), and the conclusion was that if all Principal Investigators succeed to secure the corresponding funding, then the combined programme is adequate, with few areas for improvement remaining. Therefore, late opportunity still exists for supporting and complementing the EarthCARE Validation Plan

How to cite: Koopman, R., Lefebvre, A., Maeusli, D., Wehr, T., Eisinger, M., and Piñol Solé, M.: Validation of the EarthCARE Mission, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22345, https://doi.org/10.5194/egusphere-egu2020-22345, 2020.

EGU2020-22646 | Displays | GI3.4

Next generation infrared calibration sources
not presented

Daniel Peters, Dave Smith, Robert A. McPheat, Frauke Izdebski, and Connor McGurk

 

Black body sources provide the fundamental reference for all infrared measurements from satellite radiometers. Satellite black body technology has evolved very little in the past 25 years. There is now an opportunity to introduce a range of new technologies into black body sources to address traceability and radiometric performance, and to reduce the volume, mass and power consumption of black body sub-systems. For climate class missions the ability to provide traceable radiances on orbit is essential. We outline our latest developments in these areas, including our calibration facility, and technical developments of black body technologies, and present the performance advances of these new approaches.

How to cite: Peters, D., Smith, D., McPheat, R. A., Izdebski, F., and McGurk, C.: Next generation infrared calibration sources, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22646, https://doi.org/10.5194/egusphere-egu2020-22646, 2020.

GI3.6 – Unmanned aerial vehicle (UAV) as a new, emerging instrument in Geosciences

EGU2020-1641 | Displays | GI3.6

UAV based measurements of CO2 emissions from anthropogenic point sources

Maximilian Reuter, Michael Buchwitz, Heinrich Bovensmann, and John P. Burrows

CO2 emissions are the primary cause of man-made climate change. In order to limit this, a reduction of emissions is necessary. For this reason, possibilities must be established to monitor emissions through independent measurements. A large part of the human CO2 emissions falls on point sources such as coal or gas fired power plants. On a global level, it is planned to explore these remotely by means of satellites. At the regional level, both airborne and UAV-based measurements are suitable, which can also be used for smaller sources and for the validation of the satellite data.

Here we present the development of a UAV for the determination of CO2 emissions from individual point sources by simultaneously measuring CO2 concentration, wind speed and other meteorological parameters.

A commercial UAV for industrial tasks is used as platform. CO2 is measured by a non-dispersive NIR detector with an accuracy of 1-2ppm and an ultrasonic anemometer is used for wind measurements. All relevant data is transmitted to the operator during the flight so that the flight pattern can be spontaneously adapted to the measurement data.

We will introduce the UAV including the installed sensors as well as the measuring principle and present results of the first flights.

How to cite: Reuter, M., Buchwitz, M., Bovensmann, H., and Burrows, J. P.: UAV based measurements of CO2 emissions from anthropogenic point sources, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1641, https://doi.org/10.5194/egusphere-egu2020-1641, 2020.

EGU2020-6296 | Displays | GI3.6

A Cloud Computing-based Micro-Unmanned Aerial Vehicle System for Geological Disaster Surveys

Gloria Xing, Mingzhi Zhang, Juan Ma, Zack Huang, and Cong Liu

In recent years, Unmanned aerial vehicle (UAV) tilt photography, InSAR, LiDAR and other technologies have been used in the field of geological disaster surveys and research to varying degrees, with traditional field survey methods being unable to meet the requirements of rapid and subtilized geological surveys nowadays. Thanks to the rapid development of UAV tilt photogrammetry technology, UAVs have played an important role in geological disaster emergency investigations and geological surveys. However, there are still some problems with the application of UAVs: 1. Geological disaster investigators who commonly hold degrees in geology find it difficult to learn how to operate UAVs; 2. professional UAV pilot training involves high costs and long training cycles, and meanwhile, UAV platforms and their loaded multi-lens tilt cameras are of high value, which render UAVs impossible to use as a standard accessory for geological disaster investigation teams; and 3. professional 3D modelling software is expensive and requires highly configured computer hardware, and in field scenarios, it usually has poor timeliness in terms of data processing. A micro-UAV system, mainly consisting of a UAV flight path control app (supporting Android/IOS) and a web-based data processing cloud platform, has been developed to solve the problems emerging in UAV-based geological disaster surveys, such as the difficult data collection, slow data processing, and high human involvement. The system integrates existing consumer-grade micro-UAV hardware and our newly designed UAV path planning and photogrammetry modes applicable in geological disaster surveys to achieve the fast acquisition of images, DOM, DSM, 3D models and point cloud data for geological disaster survey areas, based on high-speed processing and multi-node distributed GPU cluster technology. The main goal of this micro-UAV geological disaster surveying system is to rapidly acquire, transmit, process and distribute large-scale three-dimensional geographic information for small areas. The UAV flight path control app features one-click take-off and automatic landing, and the web data-processing cloud platform can realize one-click automatic data processing. The system has good application prospects due to its low cost and easy operation, and the fact that it can be widely used as a standard accessory by teams in various geological disaster investigations.

Keywords: micro-UAV system, cloud computing, geological disaster survey, rapid and subtilized survey

How to cite: Xing, G., Zhang, M., Ma, J., Huang, Z., and Liu, C.: A Cloud Computing-based Micro-Unmanned Aerial Vehicle System for Geological Disaster Surveys, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6296, https://doi.org/10.5194/egusphere-egu2020-6296, 2020.

EGU2020-7142 | Displays | GI3.6

Free and Open Source unmanned vehicles

Luca Delucchi and Luca Bezzi

Unmanned Vehicles (UV) are used daily for different applications around the world. However, most of the software and technologies on which they are based are closed and proprietary systems. The presentation will start by introducing the history of Unmaned Vehicle technologies, with some unknown historical info, and the different types of Unmaned Vehicles that exist. The aim of the presentation is to demonstrate the integration of free and open source systems starting from the hardware, specially the autopilot component, through some payloads and finishing with the software solutions. Different software solutions for diverse aims will be showed and compared, i.e., first the different software used to configure the UV and manage the mission and later the possible software used to manage the outputs from the mission.

How to cite: Delucchi, L. and Bezzi, L.: Free and Open Source unmanned vehicles, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7142, https://doi.org/10.5194/egusphere-egu2020-7142, 2020.

EGU2020-8300 | Displays | GI3.6

Empirical acquisition of bidirectional reflectance of tropical forest ecosystems using unmanned aerial vehicles

Wouter Maes, Lisa Bovend'aerde, Marlies Lauwers, Kathy Steppe, and Alfredo Huete

Both the sensor viewing angle and the solar angle influence the remote sensing signal of terrestrial ecosystems. This influence is characterized by the bidirectional reflectance distribution function (BRDF). Knowledge of this BRDF is needed to correctly interpret the signal, but can also provide information on vegetation characteristics and structure. Obtaining the BRDF is far from straightforward: at leaf scale, laboratory goniometers can measure reflected radiation over a range of sensor-solar angle; for very homogeneous ecosystems, such as grassland or agricultural cropland, unmanned aerial vehicles (UAVs) can be programmed as giant goniometer, scanning the BRDF of an area of up to a few m². For heterogeneous ecosystems such as forests, this is not feasible. In this case, BRDF could so far only be derived from theoretical radiation transfer models or semi-empirical models; yet these models do not always agree.

We here propose a new method for measuring BRDF of forest ecosystems with UAVs, by measuring a star-shaped area of the ecosystem, covering in total about 3600m² and capturing 6 different sensor-solar azimuth angle and three different zenith angles. This approach was applied over two sites of tropical rainforests in Queensland, Australia, with measurements with a RGB camera and a spectrometer. By repeating the flights several times during the day, we were able to test the Helmholtz reciprocity principle – that states the BRDF function of ecosystems remains the same, regardless of the solar angle – and are able to increase the range of sensor-solar angles. Our results present the first strictly empirical BRDF of tropical rainforests and confirm the importance of accurate BRDF correction of remote sensing products from forest ecosystems. 

How to cite: Maes, W., Bovend'aerde, L., Lauwers, M., Steppe, K., and Huete, A.: Empirical acquisition of bidirectional reflectance of tropical forest ecosystems using unmanned aerial vehicles, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8300, https://doi.org/10.5194/egusphere-egu2020-8300, 2020.

EGU2020-13166 | Displays | GI3.6

UAV thermal images to support the study of the expansion and contraction dynamics of river networks: a preliminary methodological approach

Massimo Micieli, Gianluca Botter, Giuseppe Mendicino, and Alfonso Senatore

River networks are dynamic entities, periodically subject to expansion and contraction processes due to natural hydrological and climatic fluctuations. The ERC project "DyNET: Dynamical River Networks" aims at providing a systematic and quantitative description of such processes. The experimental activities are focused on the mapping at the basin scale of the active (i.e., characterized by flowing water) portion of the river network with the aid of drones, satellite images and field surveys, for the collection of data useful to the modelling of evolutionary processes and the development of theories to be extended on a regional scale. The use of UAVs (Unmanned Air Vehicles) specifically concerns the observation of the space-time evolution of processes, allowing to monitor wide areas and identify the presence/absence of flowing water in the river network with the help of infrared (IR) thermal imaging cameras.

The contribution discusses the effectiveness of UAVs for river networks dynamics monitoring in the Turbolo creek network (Calabria, southern Italy). Specifically, an experimental method is described that identifies and extrapolates from thermal images the pixels representing the active river network. The method is defined based on multiple acquisitions of thermal IR images on some channelized sites in different periods of the year, weather conditions, daytimes and flight altitudes. Several surveys were carried out in autumn, winter and spring seasons, with variable cloud conditions, always repeating the same flight plan, at three different altitudes and at three different times for each day of analysis. During the experiments, air temperature data were recorded by a weather station near the test area, as well as the water temperature values ​​in a small control area in the river bed, with the ascertained presence of water, monitored by the UAV. The thermal images were analyzed on GIS software, extrapolating the pixels falling within a range of values defined from the control area. The "water pixels" thus obtained allowed, through appropriate post-processing, to reconstruct the active river network even in areas not accessible by land. The methodology developed allows defining, for different periods of the year and weather conditions, optimal altitudes and flight times to accurately identify the expansion/contraction dynamics of river networks.

How to cite: Micieli, M., Botter, G., Mendicino, G., and Senatore, A.: UAV thermal images to support the study of the expansion and contraction dynamics of river networks: a preliminary methodological approach, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13166, https://doi.org/10.5194/egusphere-egu2020-13166, 2020.

EGU2020-16008 | Displays | GI3.6

UAS magnetics as a non-invasive exploration technology

Yuleika Madriz, Robert Zimmermann, Junaidh Shaik Fareedh, Sandra Lorenz, and Richard Gloaguen

The growing demand for innovative and sustainable exploration technologies is boosting opportunities for non-invasive geophysical surveys using unmanned aerial systems (UASs). During the last few years lightweight magnetometers have been increasingly developed for their use on UASs. Aeromagnetic surveys can provide a rapid and cost-effective technology to improve the detection of shallow targets and to delineate magnetite-pyrrhotite-rich mineralizations. With low altitude flights and tight flight lines, magnetometers lifted by rotary wing UAS systems can deliver high resolution maps in small-to-medium scale areas (<100 sq.km). We propose an adaptive workflow for aeromagnetic survey acquisitions by using multi-copters that in combination with a programmed processing tool can efficiently achieve valid observations and reliable maps. Results suggest that minimizing and compensating for the magnetometers attitude changes during flight as well as the removal of temporal variations plays an important role to avoid small anomalies to go undetected. For this study we present a comprehensive data set where UAS aeromagnetic surveys aids to overcome the scale gap between ground and airborne magnetics in potentially hazardous environments where UAS have operational advantage over traditional techniques.

How to cite: Madriz, Y., Zimmermann, R., Shaik Fareedh, J., Lorenz, S., and Gloaguen, R.: UAS magnetics as a non-invasive exploration technology, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16008, https://doi.org/10.5194/egusphere-egu2020-16008, 2020.

 

Since some decades, cultural and traditional alpine farming have been changed enormously, mainly due to anthropogenic activities and economic factors: some pastures were abandoned, some others changed from farming to touristic areas (eg. ski resorts) and some others have been dramatically intensified by changing to monoculture. In consequence, these activities allow practices of deforestation, the massive use of fertilizers and pesticides, the excessive use of machinery, grading, drainage among others. Additionally, human activity have impacted on weather by resulting on low rainfall or drought extended periods. The combination of these factors result that vegetation and species are more vulnerable to the infestation of pests and diseases.

On this feasibility study, we propose the identification, mapping and classification of individual trees affected by fungal species (alternaria) in apple orchards located in South Tyrol, Italy, based on hyperspectral and thermal imagery. We have conducted terrestrial and UAV-based surveys to identify (un)healthy indivuals (trees). High spatial resolution scale consisted on terrestrial monitoring approaches based on the identification of trees and leaves, the collection of leave spectral signature based on a dedicated spectroradiometer (300 to 2000 nm) and spectral imagery of individuals. Medium spatial resolution consisted on UAV-based spectral data collection and interpretation. 30 hyperspectral bands (400 to 900 nm) in the VIR range and thermal imagery (14 µm) in combination with leave-spectral bands allowed the identification and mapping of un-healthy individuals for further treatment.

How to cite: Mejia-Aguilar, A., Prechsl, U., and Monsorno, R.: Monitoring diseases by using Hyperspectral and Thermal techniques at two different spatial scales: A feasibility study in alpine regions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16101, https://doi.org/10.5194/egusphere-egu2020-16101, 2020.

EGU2020-16797 | Displays | GI3.6

Methane emission detection and flux quantification from exploratory hydraulic fracturing in the United Kingdom, using unmanned aerial vehicle sampling

Adil Shah, Hugo Ricketts, Joseph Pitt, Jacob Shaw, Khristopher Kabbabe, Brian Leen, and Grant Allen

Unmanned aerial vehicle (UAV) sampling was used to derive high-precision methane mole fraction measurements downwind of the United Kingdom’s first onshore exploratory operation to horizontally hydraulically fracture shale rock. Sampling took place using two UAVs on five intermittent sampling days between October 2018 and February 2019. One UAV carried an on-board prototype sensor while the other was connected to a sensor on the ground, using a tethered air inlet. Both instruments used near infrared spectroscopy. Methane emissions were observed on one sampling day (14th January 2019) over a 1.4-hour sampling window, due to cold venting of methane following a nitrogen lift. The nitrogen lift procedure was used to induce gas flow during liquid unloading. The near-field Gaussian plume inversion flux quantification method was used to derive four instantaneous flux ranges (within uncertainty) from the four UAV flight surveys conducted during the emission window.

How to cite: Shah, A., Ricketts, H., Pitt, J., Shaw, J., Kabbabe, K., Leen, B., and Allen, G.: Methane emission detection and flux quantification from exploratory hydraulic fracturing in the United Kingdom, using unmanned aerial vehicle sampling, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16797, https://doi.org/10.5194/egusphere-egu2020-16797, 2020.

Soil compaction due to heavy machinery is one of the major soil degradation threats in modern agriculture. Field traffic under unfavorable weather conditions can increase bulk density and penetration resistance, reduce soil hydraulic conductivity and plant growth. An increased surface runoff caused by a decreasing infiltration further grows the effects of nutrient leaching and the eutrophication of adjacent water bodies. For soil compaction prevention, it is necessary to know where soil compaction occurs. The detection of this issue is, however, cost, time and labor intensive.

The aim of this study is to evaluate the use of UAV-based multispectral imagery analyses to detect soil compaction pattern at field scale. Therefore, UAV imagery of two sugar beet (Beta vulgaris L.) fields were captured in April, June, July and November of 2019 to analyze different crop signals. The crop surface model and the NDVI were used as a predictor to reflect plant and biomass status. The k-means clustering algorithm was used to combine plant height and NDVI to detect spatial-temporal patterns of low crop performance. Sites with lower crop performance were assumed as potential sites of soil compaction; here, further measurements (penetration resistance, infiltration rate) were conducted and soil and yield samples were taken.

First results show that (1) spatio-temporal patterns of crop performance can be found; (2) sites with low crop performance have a lower infiltration rate and lower crop yield; (3) the measurements of penetration resistance are inconclusive.

As soil compaction reduces infiltration rate and yield, this study shows first indications that it is possible to detect soil compaction via plant signals using UAV. This has a big potential for practical use as costs for drones are declining and they are gaining popularity under farmers. Thus, the use of UAV may enable farmers to monitor their fields, identify areas of soil compaction and in the following implement measures against soil compaction.

How to cite: Lindenstruth, F.: Spatio-temporal patterns of crop signals: is UAV-based multispectral imagery a suitable tool to detect soil compaction at field scale?, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19619, https://doi.org/10.5194/egusphere-egu2020-19619, 2020.

EGU2020-22365 | Displays | GI3.6

UAV-based imagery analysis with machine learning to facilitate microbial water quality monitoring of irrigation ponds

Yakov Pachepsky, Billie Morgan, Matthew Stocker, and Moon Kim

Surface waters can contain pathogenic microorganisms that may ​be detrimental to individuals consuming produce grown with irrigation. Fecal indicator organisms, primarily Escherichia coli, are commonly used to estimate the potential presence of pathogens in irrigation waters.  Concentrations of E. coli in the water of irrigation ponds are often highly variable in space and time. Water sampling that is frequent in time and dense in space, is impractical. Unmanned aerial systems (drones, or UAVs) have shown the potential to provide informative imagery. We hypothesized that the UAV-based imagery can facilitate the microbial water quality monitoring in ponds by reflecting the differences in bacteria habitats. ​Six times over the summer, we coupled monitoring of 17 water quality parameters ​of 23 locations across an irrigation pond in Maryland with 14 images ​captured by a MicaSense RedEdge M and modified GoPro cameras. The modified GoPro Images were demosaiced into red, green, and blue bands for each of the cameras. The random forest methodology was used to evaluate the accuracy and reliability of relationships between several combinations of measured ​explanatory variables, and the logarithm of the E. coli concentration as the variable to predict. Random forest models with only imagery data as the ​explanatory variables, and ​models with all measured data as explanatory variables had coefficients of determination between 0.5 ​to 0.6, and 0.6 ​to 0.7, respectively. The most important explanatory variables for the model with only imagery input were digital numbers ​obtained from the blue band of the “visible only” filter image, and from the red bands of the “infrared only” and “visible only” filter images.  When all measurements were used, the most important explanatory variables were concentrations of chlorophyll a and fluorescent dissolved organic matter, as well as and digital number​s from the red band ​of the “infrared only” filter image. There appears to be a potential for the UAV-based imagery to provide dense spatial coverage of ponds with subsequent delineation of a small number of relatively uniform zones for informed water sampling. 

How to cite: Pachepsky, Y., Morgan, B., Stocker, M., and Kim, M.: UAV-based imagery analysis with machine learning to facilitate microbial water quality monitoring of irrigation ponds, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22365, https://doi.org/10.5194/egusphere-egu2020-22365, 2020.

GI4.1 – Open session on atmosphere, land and ocean monitoring

EGU2020-1348 | Displays | GI4.1 | Highlight

Atmospheric measurements over oceans on German research vessels

Stefan Kinne

Ground-based remote sensing of atmospheric properties complements satellite remote sensing from space. Hereby the well-defined solar background of ground-based samples offers data of higher accuracy, which help to constrain (needed) assumptions in global data-sets of satellite remote sensing and earth system modeling. With ground monitoring largely limited to land or island surfaces, efforts have been made to add at least a few reference data over oceans with atmospheric remote sensing activities during ship cruises of opportunity. This presentation reports on recent voyages with German Research vessels (i.e. SONNE, MERIAN, METEOR and POLARSTERN) and how samples on these voyages have contributed to a better representation of marine properties for aerosol, trace-gases and clouds. Aside from establishing references for satellite remote sensing and modeling, relationships among different atmospheric properties also offer observational constrains for parametrizations of atmospheric processes in modeling.  

How to cite: Kinne, S.: Atmospheric measurements over oceans on German research vessels, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1348, https://doi.org/10.5194/egusphere-egu2020-1348, 2020.

Three deployments involving the NASA P-3 and ER-2 aircraft in the ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) project in September 2016, August 2017 and October 2018 were designed to study the seasonal interactions of biomass burning (BB) aerosols emanating from Southern Africa with the semi-permanent subtropical stratocumulus (Sc) cloud deck over the South-East (SE) Atlantic. We provide a science overview of all deployments, describing novel approaches for coordinating the NASA aircraft with each other, with the Bae-146 aircraft during flights near Ascension Island in 2017, and with satellite overpasses. Based on various examples, we describe the requirements for spatiotemporal coordination and the scientific benefits gleaned from successful synergy of datasets thus obtained. We provide the current status of integrative work that addresses the overarching science questions regarding aerosol-radiation-climate interactions in the region. We conclude by linking the suborbital observations with overarching observational efforts, in particular NASA’s ACCP (Aerosols, Clouds, Convection, and Precipitation) Designated Observable study, which aims to define combinations of orbital and suborbital observing system concepts for addressing integrated aerosol-cloud-climate objectives as defined in the 2017 US Decadal Survey.

How to cite: Redemann, J. and the The ORACLES science team: The NASA ORACLES airborne flight projects – lessons learned for future multi-platform missions to study aerosol-cloud-climate interactions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10956, https://doi.org/10.5194/egusphere-egu2020-10956, 2020.

EGU2020-3761 | Displays | GI4.1

Aircraft campaigns in support of the North Atlantic Climate System Integrated Studies (ACSIS)

Alexander Archibald and the The NERC ACSIS Team

The North Atlantic is witnessing major changes during the Anthropocene. These include changes in the physical climate system: in ocean and atmosphere temperatures and circulation; in sea ice thickness and extent; and in atmospheric composition, where ozone, ozone precursors and aerosols have undergone significant changes over the last few decades. Changes in aerosols over the North Atlantic have been linked to changes in sea surface temperatures (SST) and North Atlantic climate variability. A long-term research project, The North Atlantic Climate System Integrated Study (ACSIS), involving data collection and interpretation, has begun to better understand the processes and composition-climate interactions associated with these changes. Here we report on one of the major observational components of the ACSIS programme which involves repeated measurements of the composition of the North Atlantic using the NERC FAAM BAe146. To date six campaigns have taken place including three which coincided with the NASA ATom campaigns (2-4). 


In this presentation we will discuss the rationale for the aircraft project and recent results including the observation of transport of biomass burning plumes into the North Atlantic that are estimated to have originated from fires sampled as part of the NASA FIREX campaigns during the summer of 2019. We will highlight results from an intercomparison with the NASA DC-8 during our second campaign and ATom 3, which reveal good agreement in measurements of O3, CO and NOx between the two aircraft but large differences in measurements of non-methane VOCs, and we will summarise our results to-date including the comparison against chemical transport models. 

 

How to cite: Archibald, A. and the The NERC ACSIS Team: Aircraft campaigns in support of the North Atlantic Climate System Integrated Studies (ACSIS), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3761, https://doi.org/10.5194/egusphere-egu2020-3761, 2020.

EGU2020-12144 | Displays | GI4.1

Lidar-based Water Vapor, Temperature and Wind Measurements with Turbulence Resolution during the EUREC4A Field Campaign onboard RV Merian

Diego Lange Vega, Andreas Behrendt, Florian Späth, and Volker Wulfmeyer

The EUREC4A (ElUcidating the RolE of Clouds-Circulation Coupling in Climate) field campaign takes place in the lower Atlantic trades, over the ocean east of Barbados from 20 January to 20 February 2020. During this campaign, for the first time, simultaneous measurements of surface turbulence, cloud microphysical properties, cloud radiative properties, convective activity and the large-scale environment in which clouds and convection are embedded (large-scale vertical motion, thermodynamic stratification, surface properties, turbulent and radiative sources or sinks of energy).

Our new Atmospheric Raman Temperature and Humidity Sounder (ARTHUS) observes temperature and moisture profiles over the ocean with turbulence resolution of up to 10 s and 7.5 m. By this, the thermodynamic properties as well as statistics of their turbulent fluctuations in the oceanic boundary layer can be investigated in detail including relative humidity, buoyancy, CAPE, and CIN. In addition, ARTHUS is also a aerosol Raman lidar and provides profiles of particle extinction and backscatter coefficient independently at 355 nm. Two Doppler lidars – one vertical pointing the second in scanning mode – measure horizontal wind profiles as well as profiles of vertical wind fluctuations, turbulent kinetic energy, and momentum flux. The combination of the three lidars will provide synergetic data products like latent and sensible heat flux profiles. Thus, this combination allows to investigate boundary-layer properties including cloud formation and aerosol-cloud interaction.

During the EGU General Assembly, we will show our first results from the campaign.

How to cite: Lange Vega, D., Behrendt, A., Späth, F., and Wulfmeyer, V.: Lidar-based Water Vapor, Temperature and Wind Measurements with Turbulence Resolution during the EUREC4A Field Campaign onboard RV Merian, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12144, https://doi.org/10.5194/egusphere-egu2020-12144, 2020.

EGU2020-13183 | Displays | GI4.1

Progress of the Climate and Atmospheric Composition Exploring Satellites Mission (CACES) in China

Xin Wang, Xue Wu, Zhihua Zhang, and Daren Lyu

As a potential way to measure atmospheric variables with high vertical resolution and improved accuracy, the technique of Microwave and Infrared Occultation was studied. To monitor the atmospheric thermodynamic state variables (e.g., pressure, temperature, and humidity) and greenhouse gases (e.g., H2O, CO2, CH4, N2O, O3), a concept mission named Climate and Atmospheric Composition Exploring Satellites (CACES) that is based on the occultation technique of the Low Earth Orbit (LEO) satellites, was proposed to the Strategic Priority Research Program of Chinese Academy of Sciences (SPRPCAS). The mission has been approved in 2018 as a primary study to prove the possibility of observing the benchmark climate data. Designs of the constellation for the scientific objectives in climate and weather forecasts were simulated. The spatiotemporal distribution of simulated measurements was analyzed and evaluated for ensuring the desired performance. And the retrieval methods with bending angle and transmission amplitude of microwave and infrared-laser signals were studied.

How to cite: Wang, X., Wu, X., Zhang, Z., and Lyu, D.: Progress of the Climate and Atmospheric Composition Exploring Satellites Mission (CACES) in China, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13183, https://doi.org/10.5194/egusphere-egu2020-13183, 2020.

EGU2020-8988 | Displays | GI4.1

EnMAP airborne soil Greece campaign 2019

Sabine Chabrillat, Thomas Ruhtz, Georges Zalidis, Eyal Ben-Dor, Maximilian Brell, Nikos Tziolas, Robert Milewski, Daniel Berger, Saskia Foerster, Theres Kuester, Nikos Tsakiridis, Vasilis Liakopoulos, Theodora Angelopoulou, Nikiforos Samarinas, Nicolas Francos, Kerry Cawse-Nicholson, and Stefano Pignatti

In the frame of the science preparation activities for the upcoming German hyperspectral satellite mission EnMAP, an airborne survey took place in September 2019 with hyperspectral VNIR-SWIR-LWIR data using the HySpex sensor and the newly acquired Hyper-Cam LWIR camera from the GeoResearch Center Potsdam (GFZ) mounted on the airborne platform Cessna-T207A from the Free University Berlin (FUB). Although logistically complex conditions with several teams distributed in different locations, all the sites in central and northern Greece could be successfully acquired under clear sky conditions, and all data could be demilitarized providing 45 flight stripes covering a total area of 300 km2.

This abstract is focusing on the Amyntaio soil site in northern Greece, an agricultural area of variable soil composition from carbonate rich to clay/silt content to organic carbon rich fields around the lignite mine south of the area, over which 11 flight stripes could be acquired. The science goals of the Amyntaio soil campaign were: (a) Simulation of hyperspectral satellite imagery and demonstration of the potential of upcoming spaceborne hyperspectral sensors (EnMAP, CHIME) for global soil mapping and monitoring; (b) Large test and validation for existing soil algorithms such as the HYSOMA / ENSOMAP software tools for the prediction of top-soil quantitative surface properties; (c) Data validation and comparison of soil products with recent relevant satellite sensors (e.g. S2, PRISMA, ECOSTRESS); (d) Enlargement of global soil spectral libraries with harmonised standards and testbed for their use as calibration-validation data for soil spectral models.

Simultaneous to the airborne survey, an intensive ground-based campaign took place in the area focusing on the acquisition of soil data, VNIR-SWIR and LWIR in-situ data with field spectroradiometers (PSR+, ASD FieldSpec3, MEMS, Handheld FTIR), fractional vegetation cover with RGB and UAV RGB data, soil moisture, infiltrometer and spectral data in undisturbed soil crust with the SoilPRO device, and Cal-Val data acquisition at the same time than the overflight (Temperature-loggers, ASD VNIR-SWIR, handheld FTIR) over bare soils and black/white thermal targets.

We present the project objectives, selected field, airborne, satellite data, with preliminary analyses that show the high data quality and the potential of multi hyperspectral airborne campaigns as a support for basic science developments and satellite mission preparations. The results represent how more sensor flexibility can bridge the gap from in-situ to satellite scale. Further airborne flights and carefully designed in situ campaigns will allow testing and iterative improvement of new observational modalities for soil monitoring based on the integrated information from satellite platforms with the one provided by in-situ systems on the ground and air.

How to cite: Chabrillat, S., Ruhtz, T., Zalidis, G., Ben-Dor, E., Brell, M., Tziolas, N., Milewski, R., Berger, D., Foerster, S., Kuester, T., Tsakiridis, N., Liakopoulos, V., Angelopoulou, T., Samarinas, N., Francos, N., Cawse-Nicholson, K., and Pignatti, S.: EnMAP airborne soil Greece campaign 2019, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8988, https://doi.org/10.5194/egusphere-egu2020-8988, 2020.

EGU2020-1660 | Displays | GI4.1

Mapping the Friction Coefficient of Asphalt Roads Using Airborne Imaging Spectroscopy

Eyal Ben Dor and Nimrod Carmon

The purpose of this study was to evaluate the realistic feasibility of using hyperspectral remote sensing airborne data for mapping asphalt road conditions. We constructed a real-life operational scenario, where the road's dynamic friction coefficient was modeled against the reflectance information extracted from the image. The asphalt pavement's dynamic friction coefficient was measured by a standardized technique, using a Dynatest friction-measuring system. The hyperspectral data were acquired by both the Specim AisaFENIX 1K and Telops Hyper-Cam airborne sensors at a selected study site, with roads characterized by different aging conditions. The spectral radiance data were processed to provide apparent surface reflectance and emissivity using ground calibration targets. Our final dataset was comprised of thousands of clean asphalt pixels coupled with geo-rectified in situ friction measurement points. We deployed a partial least squares regression model with the PARACUDA-II spectral data-mining engine, which uses an automated outlier-detection procedure and dual validation routines—a full cross-validation and an iterative internal validation based on a Latin hypercube sampling algorithm. Our results show prediction capabilities across the visible–near infrared–shortwave infrared (0.4–2.5 mm) spectral region of R2 = 0.72 for the best available model in internal validation, and across the longwave infrared (7.6–11.4 mm) spectral region of R2=0.62  for the best available model in internal validation. Both spectral regions (optical and thermal) maintained high significant results with p < 0.0001. Using spectral assignment analysis, we located the spectral bands with the highest weight in the model, and discuss their possible physical and chemical assignments. The derived model was applied back on the hyperspectral images to predict and map the friction values of every road's pixels in the scene. We conclude that although a relatively strong prediction model can be achieved, the imaging spectroscopy technique from airborne platforms ) may open a new frontier in road safety and present a new capability for the promising airborne technology.

 

How to cite: Ben Dor, E. and Carmon, N.: Mapping the Friction Coefficient of Asphalt Roads Using Airborne Imaging Spectroscopy, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1660, https://doi.org/10.5194/egusphere-egu2020-1660, 2020.

EGU2020-19931 | Displays | GI4.1

Detection of rhododendron in a deciduous woodland using airborne hyperspectral remote sensing

Gary Llewellyn, Loreena Jaouen, Jennifer Killeen, Chloe Barnes, Luke Platts, Steve Case, and David Mothersdill

Rhododendron (Rhododendron ponticum) has been identified as an invasive non-native species (INNS) in the UK and a potential carrier of Phytophthora ramorum and therefore needs management.  This study identified the presence and location of rhododendron from airborne hyperspectral data and compared the results with Random Forests classifications of Sentinel-2 and Pleiades satellite data. The multispectral satellite systems had two limitations. The first limitation was insufficient spectral resolution to identify individual understorey species in a deciduous woodland (e.g. rhododendron, cherry laurel and holly). In this instance the satellite systems were only able to identify the presence of ‘potential rhododendron’, rather than actual rhododendron, where the term ‘potential rhododendron’ included any understorey evergreen species in a deciduous woodland. The second was insufficient spatial resolution (10m and 2m, respectively) to discriminate individual understorey plants; which resulted in the understorey being represented by a majority of mixed pixels. In this situation no more than percentage estimates of ‘potential rhododendron’ in an area could be obtained.

The airborne data used in this study were collected using a HySpex hyperspectral VNIR sensor and Phase One (80MB) survey camera; these provided a spatial resolution of 0.32m and 0.07m, respectively. The HySpex VNIR sensor had 186 bands with a full-width-half-maximum of 4.5nm. This sensor combination was shown to have sufficient spectral and spatial resolution to identify individual understorey species. Discrimination of different understorey species was achieved using a combination of spectral analysis techniques, including spectral angle mapper (SAM), and object-based-image analysis (OBIA). Furthermore, overstorey and understorey canopies were separated through the inclusion of a separate airborne LiDAR dataset, collected earlier that year.

Remotely sensed optical data were collected in leaf-off conditions to minimise the influence of the overstorey vegetation canopy. However, this introduced specific issues relating to weak sunlight and low solar illumination angles; these influenced data quality, data analysis and validation of the final classification. Methods to mitigate these issues were developed (e.g. use of masks to remove long shadows cast by trees), but challenging obstacles remained (e.g. steep north-facing terrain casting large areas in shadow). Meanwhile, validation required botanical expertise, careful consideration of the relative dates when remotely sensed data and field validation data were collected, the geographical precision of field data and an awareness of any bias incurred by shadow.  As with other remote sensing studies, the number and distribution of validation samples and the selection of training data were major considerations. However, this multi-scale study demonstrates the advantages of using airborne hyperspectral systems for species mapping in complex environments. 

How to cite: Llewellyn, G., Jaouen, L., Killeen, J., Barnes, C., Platts, L., Case, S., and Mothersdill, D.: Detection of rhododendron in a deciduous woodland using airborne hyperspectral remote sensing, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19931, https://doi.org/10.5194/egusphere-egu2020-19931, 2020.

EGU2020-18367 | Displays | GI4.1

Airborne measurements over Korea using the KMA/NIMS atmospheric research aircraft (NARA)

Chulkyu Lee, Suengpil Jung, Ji-Hyoung Kim, Hyojin Yang, Heejong Ko, Jonghwan Yun, Seungbum Kim, and Sangwon Joo

Airborne campaigns for the meteorological and environmental research have been conducted in regional and global scales. The aircraft is increasingly considered as one of the best platforms to get the atmospheric spatial information, especially over sea. National Institute of Meteorological Sciences (NIMS), Korea Meteorological Administration (KMA) has been utilizing an aircraft (Beechcraft King Air 350HW) equipped with 25 scientific mission instruments since 2018, in order to fill in observational gaps and observe the upper level of troposphere at higher temporal/spatial resolution and to test advanced observational and experimental techniques, resulting in enhancing meteorological technologies and research capabilities. Our airborne observation plans using the aircraft are designed over the Korean Peninsula; preceding observation of severe weather (e.g., tropical cyclone, heavy rainfall and snowfall), greenhouse gas monitoring, environmental meteorology monitoring (e.g., Asian dust), and cloud physics and cloud seeding. In particular, preceding observation of severe weather which mainly uses dropsondes focuses on characterizing generation/migration of severe weather phenomena and investigating meteorological precursors sensitive to severe weather and variations in its thermo-dynamical structures, and then improving predictability of numerical models with the data assimilation. Here, we discuss current status and future plan of our airborne measurement campaigns over the Korean Peninsula, with examples of data observed from the aircraft.

How to cite: Lee, C., Jung, S., Kim, J.-H., Yang, H., Ko, H., Yun, J., Kim, S., and Joo, S.: Airborne measurements over Korea using the KMA/NIMS atmospheric research aircraft (NARA), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18367, https://doi.org/10.5194/egusphere-egu2020-18367, 2020.

EGU2020-18805 | Displays | GI4.1

The Sentinel-5 Precursor VAlidatioN and calibraTion Experiment (SVANTE)

Michel Van Roozendael, Frederik Tack, Alexis Merlaud, Dirk Schuettemeyer, Frank Hase, Andreas Richter, Andreas Meier, Mahesh Kumar Sha, Martine De Mazière, Arnoud Apituley, Doina Nicolae, Andreaa Calcan, Thomas Ruhtz, Cyril Crévoisier, Anke Roiger, Angelika Dehn, and Claus Zehner

Launched on 13 October 2017, Sentinel 5 Precursor (S-5p) is the first mission of the Copernicus Programme dedicated to the monitoring of air quality, climate, ozone and UV radiation. The S-5p characteristics, in particular its fine spatial resolution of 3.5 x 5.5 km2, introduce new opportunities for science and applications requiring to carefully assess the quality and validity of the generated data products by comparison with independent measurements and analyses.

While the routine validation and QA/QC of the S-5p operational products is performed within the ESA Mission Performance Center (MPC) based on a limited number of Fiducial Reference Measurements (FRM), additional validation activities including field campaigns are conducted in research mode as part of the S-5p Validation Team (S5PVT). The validation activities bring together various teams and instruments and provide a more in-depth, complete insight into the S-5p instrument performance and the fitness for purpose of its data products.

Here, we present observational deployments planned to take place in 2020-2021 in the context of the Sentinel 5p VAlidatioN and calibraTion Experiment (SVANTE). A first set of activities concentrates on the main S-5p UV-Vis tropospheric products (NO2, HCHO and SO2). Airborne measurements, including both in-situ spiral and remote sensing mapping flights, are planned over cities and industrial areas in Romania (Bucharest; Jiu valley), the German Ruhr area (Cologne; Duisburg; Dusseldorf) and Berlin, Belgium (Antwerp and Brussels), The Netherlands (Rotterdam and Cabauw), as well as the southern part of The Persian Gulf. These operations will be supported by ground-based measurements using Pandora, MAX-DOAS, car-DOAS, sun-photometer, ceilometer, lidar, etc. Over Berlin and Bucharest, the aim is to perform recurrent airborne observations with hyperspectral imagers in order to accumulate mapping data during approximately one full year, under variable meteorological and air quality conditions, as well as different satellite overpass configurations.

A second set of activities will focus on the validation of the SWIR data products (CO and CH4). COCCON (COllaborative Carbon Column Observing Network) portable low-resolution EM27/SUN FTIR spectrometers will be deployed for an extended period at different sites in order to obtain a good coverage of geophysical parameters and different ground scenes.

Additionally, synergies will be created with large field campaigns, such as the Asian Summer Monsoon Chemical and Climate Impact Project (ACCLIP) and the 2020 HYTES Joint European Campaign, which will provide airborne measurements of NO2, CO and CH4 columns and vertical profiles.

The various airborne and ground-based measurements will produce a comprehensive ensemble of reference datasets. For each product, a core team will coordinate validation tasks, making use of data collected in all relevant instrumental deployments.

How to cite: Van Roozendael, M., Tack, F., Merlaud, A., Schuettemeyer, D., Hase, F., Richter, A., Meier, A., Sha, M. K., De Mazière, M., Apituley, A., Nicolae, D., Calcan, A., Ruhtz, T., Crévoisier, C., Roiger, A., Dehn, A., and Zehner, C.: The Sentinel-5 Precursor VAlidatioN and calibraTion Experiment (SVANTE), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18805, https://doi.org/10.5194/egusphere-egu2020-18805, 2020.

EGU2020-2753 | Displays | GI4.1

The Present and Future Role for sUAS in Atmospheric Sciences

Bruce Baker, Ed Dumas, Temple Lee, and Michael Buban

The scientific community is beginning to see how our environment reacts to changes on an unprecedented time and space scale with the utilization of small Unmanned Aircraft Systems or sUAS.  These new observation platforms can be utilized for flood forecasting, local weather forecasting, monitor wildlife, improve hurricane forecasts and this the tip of the iceberg. This technology is a new tool that will allow the scientific community to observe the environment on time and space scales that are unprecedented.  This particular talk will primarily address the future of these observing platforms as it relates to advancing the atmospheric sciences. UAS’s are rapidly becoming the new technology that can acquire low-level environment information more frequently, in support of higher-resolution model forecasts of severe thunderstorm and tornado potential, improvement in  Environmental Model Prediction, provide environmental  information to provide better support  the spread of wildfires and smoke, as well as wildfire imagery for Incident Command and more complete/accurate storm damage surveys.  One of the end goals would be to have  a nationwide network of sUAS providing near-continuous observations of thermodynamic parameters, NDVI, surface sensible heat and wind speed and direction. Most of these observations are being done on a regular basis and some will be attainable in the future as technology progresses and National Airspace becomes more accessible. 

How to cite: Baker, B., Dumas, E., Lee, T., and Buban, M.: The Present and Future Role for sUAS in Atmospheric Sciences, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2753, https://doi.org/10.5194/egusphere-egu2020-2753, 2020.

EGU2020-17069 | Displays | GI4.1

Applications of an UAV aerogeophysical integrated survey system(iUAGS) in china

Ning Lu, yongzai Xi, hongshan Zheng, junjie Liu, and shan Wu

iUAGS is an emerging UAV aerogeophysical integrated survey system ( magnetic & radiation) based on the rainbow series UAV(the CH-3),which has many advantages such as long-endurance,low altitude, all-day time work ability, high precision,low cost,etc.It’s leading researched and developed by Institute of Geophysical and Geochemical Exploration (IGGE) of China Geological Survey (CGS).Since 2013,more than 150,000 kilometers’ pretty good and high quality geophysical data have been acquired using iUAGS in Duobaoshan of Heilongjiang province , Karamay and Kashi area of Xinjiang province,YanCheng of Jiangsu province in china.And a new survey hosted by IGGE is now working for earth deep probe project in southern china.With the development of UAV and aerogeophysical technology,We believe that iUAGS will be widely and better used in more fields.  

How to cite: Lu, N., Xi, Y., Zheng, H., Liu, J., and Wu, S.: Applications of an UAV aerogeophysical integrated survey system(iUAGS) in china, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17069, https://doi.org/10.5194/egusphere-egu2020-17069, 2020.

EGU2020-17779 | Displays | GI4.1

DVAS -Data Visualization and Analysis Software: processing and analysis of the radiosounding data for the next WMO Upper-Air Instruments Intercomparaison - UAII2021.

Giovanni Martucci, Ruud Dirksen, Gonzague Romanens, Alexander Haefele, Frédéric P.A. Vogt, Michael Sommer, Christian Félix, Volker Lehmann, Holger Voemel, David Edwards, Stewart Taylor, Tom Gardiner, Mohd. Imran Ansari, Emad Eldin Mahmoud, Tim Oakley, Isabelle Ruedi, Krunoslav Premec, Franz Berger, and Bertrand Calpini

The forthcoming Upper-Air Instruments Intercomparaison (UAII2021) is organized under the auspices of the World Meteorological Organization (WMO) with the purpose to improve the quality of upper air observing systems and to develop the knowledge and expertise of national meteorological services (NMHS). The participating radiosonde systems (RS) are representative for those currently employed in the global observational network. A novelty with regard to previous RS intercomparison campaigns is to adopt principles and practices well established in the GCOS Reference Upper Air Network (GRUAN). This includes using GRUAN reference data products (GDPs) in the comparison of the RS. A distinguishing feature of a GDP is that the data are traceable to SI units. The data measured by a GDP are fully characterized in terms of their vertically-resolved uncertainty. This means that for each data point measured by the GDP at altitude z the obtained value V is represented as V(z) ± ΔV(z). Another novelty is the use of open source software for data analysis and visualization. The Data Visualization and Analysis Software (DVAS) is currently being developed and, as a basic feature, will use GDPs to establish the reference against which the performances of the participating RS are evaluated. This ensures a fair and transparent approach in the intercomparison of the RS. The DVAS uses a statistical combination of the available GDPs (two GDPs being the minimum number required) to act as a working standard (WS). Each data point measured by a GDP at the altitude z is assessed for consistency with the data points measured by the other GDPs and, if consistent, they are retained for calculation of the WS. In other words, the values V(z) ± ΔV(z) from the GDPs are evaluated and added together to yield the combined values for the measured parameter and its uncertainty. The evaluation of the values V(z) ± ΔV(z) consists of a consistency test, i.e. the values V(z) ± ΔV(z) should lie within the uncertainties of the other GDPs. The details of the consistency test, including the case when the test fails, will be provided in the presentation of the DVAS.

In addition to the evaluation of the RS performances in terms of their mean bias and variability, each RS is assessed for its ability to be fit for purpose with respect to different application areas based on the Observing Systems Capability Analysis and Review Tool (OSCAR table of requirements, https://www.wmo-sat.info/oscar/). For example, a RS can be affected by a too-large bias/ variability with respect to the reference WS for applications in the area of high-resolution numerical modelling, but can be fit for the purposes of global modelling.

How to cite: Martucci, G., Dirksen, R., Romanens, G., Haefele, A., Vogt, F. P. A., Sommer, M., Félix, C., Lehmann, V., Voemel, H., Edwards, D., Taylor, S., Gardiner, T., Ansari, M. I., Mahmoud, E. E., Oakley, T., Ruedi, I., Premec, K., Berger, F., and Calpini, B.: DVAS -Data Visualization and Analysis Software: processing and analysis of the radiosounding data for the next WMO Upper-Air Instruments Intercomparaison - UAII2021., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17779, https://doi.org/10.5194/egusphere-egu2020-17779, 2020.

EGU2020-19600 | Displays | GI4.1

Planning for LOTOS: A New LOwer Troposphere Observing System

Terry Hock, Tammy Weckwerth, Steve Oncley, William Brown, Vanda Grubišić, and Wen-Chau Lee

The National Center for Atmospheric Research Earth Observing Laboratory (EOL) proposes to develop the LOwer Troposphere Observing System (LOTOS), a new integrated sensor network that offers the potential for transformative understanding of the lower atmosphere and its coupling to the Earth's surface. 

 

The LOTOS sensor network is designed to allow simultaneous and coordinated sampling both vertically, through the atmospheric planetary boundary layer, and horizontally, across the surrounding landscape, focusing on the land-atmosphere interface and its coupling with the overlying free troposphere. The core of LOTOS will be a portable integrated network of up to five nodes, each consisting of a profiling suite of instruments surrounded by up to fifteen flux measuring towers. LOTOS will provide an integrated set of measurements needed to address outstanding scientific challenges related to processes within the atmospheric surface layer, boundary layer, and lower troposphere. LOTOS will also enable novel quantification of exchanges of biogeochemical and climate-relevant gases from microscale up to regional scale. 

 

LOTOS’ uniqueness lies in its ability to simultaneously sample both horizontally and vertically as an integrated system, but also in its flexibility to be easily relocated as a portable field-deployable system suitable for addressing a wide range of research needs. LOTOS will provide real-time data quality control, combine measurements from a variety of sensors into integrated data products, and provide real-time data displays. It is envisioned that LOTOS will become part of the deployable NSF Lower Atmosphere Observing Facilities (LAOF) and thus be available to a broad base of NSF users from both observational and modeling communities. LOTOS offers the potential for transformative understanding of the Earth and its atmosphere as a coupled system. This presentation will describe the background, motivation, plan, and timeline for the LOTOS’ proposed development.

How to cite: Hock, T., Weckwerth, T., Oncley, S., Brown, W., Grubišić, V., and Lee, W.-C.: Planning for LOTOS: A New LOwer Troposphere Observing System, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19600, https://doi.org/10.5194/egusphere-egu2020-19600, 2020.

EGU2020-7041 | Displays | GI4.1 | Highlight

A 12-month UK air quality aircraft campaign and model evaluation

Eleanor R. Smith, Angela Mynard, Rachel N. McInnes, Matthew C. Hort, Paul Agnew, Joss Kent, Andy Wilson, David Tiddeman, James Bowles, Justin M. Langridge, Kirsty Wivell, Kate Szpek, Paul A. Barrett, Robert King, and Alexander T. Archibald

Surface concentrations of pollutants in the UK are generally well observed and column averaged data is increasingly available from satellites. However, there remains limited data on the vertical distribution of key pollutants in the UK boundary layer.

As part of the Strategic Priorities Fund Clean Air programme, the Met Office Civil Contingencies Aircraft (MOCCA) has been instrumented to enable measurements of ozone, nitrogen dioxide, sulphur dioxide and particulate matter (PM2.5 and PM10) to be made in the UK boundary layer.

These ongoing observations are being used to evaluate Air Quality in the Unified Model (AQUM), improve air quality forecasts and hence ultimately improve our confidence in the model data used to perform assessments of the health impacts of pollution in the UK.

Here we present our methodology, initial investigation of model and aircraft data from flights during the first 6 months of the project and future plans for this work.

How to cite: Smith, E. R., Mynard, A., McInnes, R. N., Hort, M. C., Agnew, P., Kent, J., Wilson, A., Tiddeman, D., Bowles, J., Langridge, J. M., Wivell, K., Szpek, K., Barrett, P. A., King, R., and Archibald, A. T.: A 12-month UK air quality aircraft campaign and model evaluation, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7041, https://doi.org/10.5194/egusphere-egu2020-7041, 2020.

EGU2020-21801 | Displays | GI4.1

Cyprus enters the space arena with "Excelsior " H2020 Teaming project and the Eratosthenes Centre of Excellence: Why Cyprus? Why Excelsior? What are the needs and opportunities?

Kyriakos Themistocleous, Diofantos Hadjimitsis, Gunter Schreier, Haris Kontoes, Albert Ansmann, Giorgos Komodromos, Silas Michaelides, Kyriacos Neocleous, Christiana Papoutsa, Rodanthi Mamouri, Egbert Schwarz, Ioannis Papoutsis, Johannes Bühl, Argyro Nisantzi, Christodoulos Mettas, Christos Danezis, and Marios Tzouvaras

Cyprus enters the space arena with the ‘EXCELSIOR’ project. ‘EXCELSIOR’ is expected to bring change in many aspects, including new opportunities for researchers, enhanced skills development for future experts in the Earth Observation and Geoinformation sector on a local, national, European and global level. Due to its geographical proximity, ‘EXCELSIOR’ can become a hub for partners in Middle Eastern and Northern African countries. Cyprus’s unique geostrategic position can support Earth Observation from satellites programmes in three continents and provide valuable services in the processes of satellite calibration and validation. The ERATOSTHENES Centre of Excellence (ECoE), with its expertise and infrastructure, could further complement the existing network of international ground stations. Cyprus is ideally located to host the ECoE, due to its climate, which is characterized by 300 days of sunshine a year, providing excellent weather conditions for cloud free satellite images.

There are some distinct needs and opportunities that motivate the establishment of an Earth Observation Centre of Excellence in Cyprus. The needs include: i) to establish a Supersite for aerosol and cloud monitoring in the Eastern Mediterranean, Middle East and North Africa (EMMENA): strong demand for EO monitoring to provide data to evaluate the extent of pollution and climate change, especially in the EMMENA region; ii) to observe droughts and water shortages in the EMMENA region; iii) to adopt Rehabilitation programmes in EMMENA; iv) to reduce Disaster Risk and v) to create a Regional Digital Innovation Hub for Earth Observation in Cyprus. The foreseen opportunities include: i) the ECoE has the potential to become a catalyst for facilitating and enabling Regional, European and International cooperation; ii) the Eco E can capitalise on the favourable environmental, weather and climatic conditions of Cyprus to conduct cutting-edge research with impact in various sectors, including climate change, marine, solar energy, etc.; iii) the development of the Cyprus Space Strategy, which can be exploited for further Earth observation research and applications; iv) create a unique European capacity in Cyprus by mobilizing internal national assets and consolidating European EO capabilities in Cyprus to serve EMMENA. The ECoE will procure and develop the European Satellite Ground Stations covering the EMMENA region; v) accessing funding instruments for Earth Observation at the national and European Level and vi) the development of Big Data management and analytics.                              

The EXCELSIOR project has received funding from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No 857510 and from the Government of the Republic of Cyprus through the Directorate General for the European Programmes, Coordination and Development.

How to cite: Themistocleous, K., Hadjimitsis, D., Schreier, G., Kontoes, H., Ansmann, A., Komodromos, G., Michaelides, S., Neocleous, K., Papoutsa, C., Mamouri, R., Schwarz, E., Papoutsis, I., Bühl, J., Nisantzi, A., Mettas, C., Danezis, C., and Tzouvaras, M.: Cyprus enters the space arena with "Excelsior " H2020 Teaming project and the Eratosthenes Centre of Excellence: Why Cyprus? Why Excelsior? What are the needs and opportunities?, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21801, https://doi.org/10.5194/egusphere-egu2020-21801, 2020.

EGU2020-13490 | Displays | GI4.1

Emissions from natural gas and oil operations: The airborne METHANE-To-Go field campaign in the Persian/Arabian Gulf region

Heidi Huntrieser, Anke Roiger, Daniel Sauer, Hans Schlager, Mariano Mertens, and Stefan Schwietzke

About 60% of global methane (CH4) emissions are due to human activities. Since the Paris Agreement was signed in 2016, an increasing effort has been devoted to accelerate the greenhouse-gas-emissions mitigation. Afore in 2014, the Oil and Gas Climate Initiative (OGCI) formed, which is an international industry-led organization including 13 member companies from the oil and gas industry, representing 1/3 of the global operated oil and gas production. The Environmental Defense Fund (EDF) and United Nations Environment Programme (UNEP) funded project METHANE-To-Go aims to focus on trace gas emissions from the natural gas and oil operations in the Persian/Arabian Gulf region, a wealthy region which contains about 50% of the world´s oil reserves. The project is coordinated by the Deutsches Zentrum für Luft- und Raumfahrt (DLR) and envisages to carry out airborne in-situ measurements with the German Deutsches Zentrum für Luft- und Raumfahrt (DLR) Falcon-20 in autumn 2020 in cooperation with local OGCI partners.

The flaring, venting and combustion processes produce large amounts of CH4, a greenhouse gas that is ~84 times more potent than CO2 (measured over a 20-year period) and in focus of current mitigation strategies trying to reduce global warming. However, there is a huge lack of detailed CH4 measurements worldwide and especially from the Gulf region. The contribution from this region to the global CH4 mass balance is presently unknown. Furthermore, recently a first global satellite-derived SO2 emissions inventory was established based on measurements with the Ozone Monitoring Instrument (OMI) on the NASA Aura satellite showing a number of SO2 hot spots in the Persian/Arabian Gulf region. The Middle East region was high-lighted as the region with the most missing SO2 sources compared to reported sources in the global emission inventories. The petroleum industry operations are mainly responsible for these emissions, since high amounts of H2S are trapped in oil and gas deposits and released during extraction. In recent years, the air quality in this region has worsened dramatically and concurrently global warming is especially strong.  

The DLR Institute of Atmospheric Physics plan the performance of airborne in-situ measurements to probe the isolated, outstanding emission plumes from the different CH4 and SO2 sources in the southern part of the Gulf region as mentioned above. A novel dual Quantum Cascade Laser (QCL) instrument based on laser absorption spectroscopy will be deployed to measure CH4 and CO, and related trace gases as CO2 and C2H6, which can be used to distinguish between different CH4 sources (flaring, venting and combustion). An ion-trap chemical ionization mass spectrometer (IT-CIMS) is foreseen for the measurements of SO2. Both instruments operate with a high precision/accuracy and a temporal resolution of 0.5 to 1s, which covers a horizontal distance of roughly 50-200 m during the flight. Measurements of further trace species are also foreseen (e.g. NO, NOy, and aerosols) and simulations with particle dispersion models for flight planning and post analyses (HYSPLIT and the EMAC related model MECO(n)). Furthermore, satellite validation is envisaged with the TROPOMI instrument on Sentinel-5P (focus on CH4 and SO2).

How to cite: Huntrieser, H., Roiger, A., Sauer, D., Schlager, H., Mertens, M., and Schwietzke, S.: Emissions from natural gas and oil operations: The airborne METHANE-To-Go field campaign in the Persian/Arabian Gulf region , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13490, https://doi.org/10.5194/egusphere-egu2020-13490, 2020.

EGU2020-2294 | Displays | GI4.1

FTIR time series of tropospheric HCN in eastern China and source attribution

Youwen Sun, Pandai Dai, and Hao Yin

We analyzed seasonality and interannual variability of tropospheric HCN column amounts in densely populated eastern China for the first time. The results were derived from solar absorption spectra recorded with ground-based high spectral resolution Fourier transform infrared (FTIR) spectrometer at Hefei (117°10′E, 31°54′N) between 2015 and 2018. The tropospheric HCN columns over Hefei, China showed significant seasonal variations with three monthly mean peaks throughout the year. The magnitude of the tropospheric HCN column peak in May > September > December. The tropospheric HCN column reached a maximum of (9.8 ± 0.78) × 1015 molecules/cm2 in May and a minimum of (7.16 ± 0.75) × 1015 molecules/cm2 in November. In most cases, the tropospheric HCN columns at Hefei (32°N) are higher than the FTIR observations at Ny Alesund (79°N), Kiruna (68°N), Bremen (53°N), Jungfraujoch (47°N), Toronto (44°N), Rikubetsu (43°N), Izana (28°N), Mauna Loa (20°N), La Reunion Maido (21°S), Lauder (45°S), and Arrival Heights (78°S) that are affiliated with the Network for Detection of Atmospheric Composition Change (NDACC). Enhancements of the tropospheric HCN columns were observed between September 2015 and July 2016 compared to the counterpart measurements in other years. The magnitude of the enhancement ranges from 5 to 46% with an average of 22%. Enhancement of tropospheric HCN (ΔHCN) is correlated with the coincident enhancement of tropospheric CO (ΔCO), indicating that enhancements of tropospheric CO and HCN were due to the same sources. The GEOS-Chem tagged CO simulation, the global fire maps and the PSCFs (Potential Source Contribution Function) calculated using back trajectories revealed that the seasonal maxima in May is largely due to the influence of biomass burning in South Eastern Asia (SEAS) (41 ± 13.1%), Europe and Boreal Asia (EUBA) (21 ± 9.3%) and Africa (AF) (22 ± 4.7%). The seasonal maxima in September is largely due to the influence of biomass burnings in EUBA (38 ± 11.3%), AF (26 ± 6.7%), SEAS (14 ± 3.3%), and Northern America (NA) (13.8 ± 8.4%). For the seasonal maxima in December, dominant contributions are from AF (36 ± 7.1%), EUBA (21 ± 5.2%), and NA (18.7 ± 5.2%).The tropospheric HCN enhancement between September 2015 and July 2016 at Hefei (32°N) were attributed to an elevated influence of biomass burnings in SEAS, EUBA, and Oceania (OCE) in this period. Particularly, an elevated fire number in OCE in the second half of 2015 dominated the tropospheric HCN enhancement in September – December 2015. An elevated fire number in SEAS in the first half of 2016 dominated the tropospheric HCN enhancement in January – July 2016.

How to cite: Sun, Y., Dai, P., and Yin, H.: FTIR time series of tropospheric HCN in eastern China and source attribution, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2294, https://doi.org/10.5194/egusphere-egu2020-2294, 2020.

EGU2020-18175 | Displays | GI4.1

Validation of year-round Stepped Frequency Microwave Radiometer (SFMR) measurement of sea surface wind speed around the Korean Peninsula during 2018-2019

Ji-Hyoung Kim, Chulkyu Lee, Hyojin Yang, Suengpil Jung, Heejong Ko, Jonghwan Yun, Seongeun Hong, Seungbum Kim, and Sangwon Joo

Korea Meteorological Administration/National Institute of Meteorological Sciences (KMA/NIMS) has adopted KMA/NIMS Atmospheric Research Aircraft (NARA) since the beginning of 2018. NARA has performed year-round airborne measurement of Sea surface Wind Speed (SWS) using Stepped Frequency Microwave Radiometer (SFMR) during 2018-2019. Total 84 flights of SFMR SWS measurements during this period were analyzed by comparing to concurrent measurements of KMA marine buoy. SFMR SWS around the Korean peninsula during the same period was 6.34±4.95 m s-1. SFMR SWS was appeared to be 12.3% larger than those of KMA marine buoy and mean Bias Difference (BD) was 0.69 m s-1. However, SFMR SWS and KMA marine buoy were correlated well to each other (R2~0.80). The BD was decreased with increasing SWS, this agreed well with results of previous studies (Klotz et al., 2014), however, SFMR SWS measurement showed still reliable even in low SWS environment (< 15 m s-1). For more accurate measurement of SFMR SWS, parameters such as the flight altitude (swath area) and pre-input values (sea surface temperature, salinity) should also be considered. Also, this result can be a comparison reference for those of satellite-borne sensors, as well.

How to cite: Kim, J.-H., Lee, C., Yang, H., Jung, S., Ko, H., Yun, J., Hong, S., Kim, S., and Joo, S.: Validation of year-round Stepped Frequency Microwave Radiometer (SFMR) measurement of sea surface wind speed around the Korean Peninsula during 2018-2019, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18175, https://doi.org/10.5194/egusphere-egu2020-18175, 2020.

EGU2020-725 | Displays | GI4.1

UAV magnetic survey for geological exploration: A case study of the Synnyr Massif, Buryatia, Russia

Igor Maev, Anastasiya Karaman, and Alexander Kajukov

The Synnyr alkaline massif is a concentrically zoned body located in the Baikal Vitim folded area, Holodninskiy graben. It is controlled by the deep-seated Precambrian Baikal-Synnyr fault, while major rock types of the massif were dated as 230-350 Ma (Kostuk et al., 1990; Mitrofanova 2009). However, there were no young strike-slip faults or thrusts identified throughout the massif. Studying the area is compounded by the climate and landscape conditions, which makes the airborne geophysical survey a very cost-effective mapping tool. Main geological investigations of the Synnyr massif were made in the 1960s and in the 1980s. In those times, an airborne geophysical survey was not as accurate as it was required and didn’t bring up any significant results.

The next stage of Synnyr massif exploration began in 2016. The first airborne magnetic survey based on unnamed aerial vehicles (UAV) was made in 2018 and increased our knowledge about the geological situation in the studying area. Main goals of the UAV magnetic survey were tracing highly magnetic foidal gabbroids named shonkinites, which are located in the central part of the ore zone, and mapping major faults.

The airborne geophysical complex included a multirotor aerial vehicle and quantum magnetometer with a rubidium magnetic field sensor that was placed in the special gondola and attached to the UAV. The study area was surveyed at 20 meters height with detailed terrain following and accuracy of magnetic field measurements comparable with the ground magnetic survey.

As a result, airborne magnetic data helped to clarify geological structure and tectonics in the areas covered with glacier or without any outcrops. Furthermore, magnetic field measurements allowed to locate faults and lineaments which were not traced in previous geological studies of the Synnyr massif and to make an assumption about the neotectonic activity of Baikal-Synnyr fault system.

Due to cost-efficiency, informativeness and high accuracy of geophysical surveys based on UAV, we are planning to continue research and extend the studying area.

References:

Mitrofanova N.N. Report for Aldan-Transbaikal geological maps, 2009

Kostuk V.P., Panina L.I., Zhidkov A. Y., Orlova M.P., Bazarova T.Y. Potassium alkaline magmatism in Baikal-Stanovoi rift system, 1990

How to cite: Maev, I., Karaman, A., and Kajukov, A.: UAV magnetic survey for geological exploration: A case study of the Synnyr Massif, Buryatia, Russia, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-725, https://doi.org/10.5194/egusphere-egu2020-725, 2020.

In this paper, we focus on UAVs (Unmanned Aerial Vehicles) positioning in GPS-denied environments and proposes a navigation mode of “track reckoning + relative ranging + heading constraint”. Internal sensors (gyros, accelerometer, barometer, etc.) measure the self-motion to obtain the flight path and attitude, and the external sensors identify and measure the relative ranging to achieve peer-to-peer constraint for UAVs. In order to guide the swarm to the intended destination when GPS is denied, the ground anchor nodes are set to provide relative heading constraints to the UAVs for target and trajectory guidance. We propose a hybrid centralized-distributed scheme including 20 UAVs, as well as its dynamic motion model and measurement model. To improve the ranging accuracy in the actual RSSI measurement, we analyze the influence of antenna pattern inhomogeneity and channel variation, respectively. The former mainly determines an antenna radiation function related to the yaw angle and relative position between the two measuring UAVs. The latter uses overlapping Allan variance to analyze and identify the measurement noises from outfield tests, that is, quantization noise, flicker noise, random walk noise and Gaussian white noise, which to some extent bridges the difference between the theoretical model and the practical measurement of RSSI. In this way, an improved extended Kalman filter is to predict and correct the colored noise by adaptively integrating the current peer-to-peer radio ranging performance and its Allan variance. To prove the effectiveness of this approach, simulation results base on practical noise modeling are demonstrated.

How to cite: Xiaofeng, O., Daqian, L., and Tianbao, D.: Cooperative Navigation of UAVs in GPS-denied area using an extended Kalman filter with colored RSSI measurements, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4508, https://doi.org/10.5194/egusphere-egu2020-4508, 2020.

EGU2020-19251 | Displays | GI4.1

Hyper-Spectral Imaging for Earth Observation Applications

Melina Maria Zempila, Michelle Hamilton, and Hugh Mortimer

In this study, we present a hyper-spectral imaging (HSI) system that focuses on the spectral window 470-970 nm and meets the demands of static sampling and remote sensing when mounted on an Unmanned Aerial System (UAS).

The system comprises two HS cameras, a compact industrial PC and a battery pack. It has a total weight of <1.8kg, including the bracket for mounting to an active DJI Ronin gimbal. A labview interface was also developed to collect, process and analyse the images from the two HS cameras. The software has the ability to set the parameters for the cameras’ exposure times and capture frequency, while it can provide the digital counts at a single point of the image or the averaged counts over a rectangular area of the image. For the purposes of aerial applications, the program provides the ability of delayed start and sequentially image capture.

For the calibration of the raw HS images, an offline workflow is developed to derive absolute reflectance values. The processing chain includes dark and vignetting correction, spectral response characterization, digital number to reflectance conversion and hyperspectral data cube reconstruction.

The system has been already deployed in several in house studies: detection of dothistroma in Scots pine needles, starch detection in apples and bananas, and avocados maturity indication, while aerial imagery was also acquired during field campaigns in the UK and China aiming to create a tree species distribution map and to early identify tree health issues.

The development of the system is dynamic as technology is moving forward and the demand for light-weighted multi-sensor UAS surveys is increased during the last decade. Furthermore, the calibration processes and data analysis techniques are constantly updated to meet international requirements and push the accuracy of the products to the highest standards.

How to cite: Zempila, M. M., Hamilton, M., and Mortimer, H.: Hyper-Spectral Imaging for Earth Observation Applications, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19251, https://doi.org/10.5194/egusphere-egu2020-19251, 2020.

Artificial light at night (ALAN) has become a major concern in recent years due to its impact on the health of human beings and the ecosystems. As a result, there is a surge of light pollution research not only on night sky brightness, but also on assessments of impacts on both ecology and society.

We have set up an interdisciplinary project in Hungary since September 2017, to not only study the impacts of change in lighting technology on patterns of ALAN (with emphasis on the areas within and around national parks in Hungary), but also facilitate national and international cooperations in light pollution research. We refer to this project as Living Environmental Laboratory for Lighting (LELL). Specifically, the project covers the following areas:

1. Development of new techniques for night sky radiometry and spectrometry
We are developing techniques for night sky multispectral measurements using commercially available cameras with interchangeable lens, calibrated by high sensitivity spectroradiometer, in order to quantify night sky condition and identify sources of artificial light at high resolution not achieveable by systems based on panchromatic sensors or fisheye lenses. In addition, we will compare the results from our ground-based measurements with satellite-based observations.

2. Modeling of night sky patterns in national parks of Hungary
We have developed a Monte-Carlo method of modeling light pollution, which can also be used for investigating effects of aerosols and clouds on the propagation of artificial light.

3. Impact assessments of ALAN through measurements
The public lighting was remodeled to LED-based systems in two areas close to national parks, one of which in the Zselic region in Southwestern Hungary, and another in Bükk in Northern Hungary. Using the techniques above, we are monitoring the change in night sky brightness and color, as well as the impact on flora and fauna.

4. Recommendations on future assessments and mitigations of light pollution
With our experience gain within the duration of this project, we will inform the light pollution research community of standardizing methodologies for monitoring light pollution, as well as giving recommendations for managing public lighting assets to reduce the impacts of light pollution.


Acknowledgement
This project is supported by the European Union and co-financed by the
European Social Fund (Grant no. EFOP–3.6.2–16–201–00014: Development of
international research environment for light pollution studies)

How to cite: Tong, K. P. and Kolláth, Z.: Living Environmental Laboratory for Lighting — A comprehensive study of interactions of artificial lighting and wildlifes, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6065, https://doi.org/10.5194/egusphere-egu2020-6065, 2020.

EGU2020-7512 | Displays | GI4.1

PICASSO: a PICo-satellite for Atmospheric and Space Science Observations

Noel Baker, Michel Anciaux, Emmanuel Dekemper, Philippe Demoulin, Didier Fussen, Didier Pieroux, and Sylvain Ranvier

The recent surge in the development of small satellite platforms could offer the opportunity to significantly decrease the overall cost of science missions, if suitable instruments can be operated from such platforms. PICASSO is a CubeSat demonstration mission initiated by the Belgian Institute for Space Aeronomy and implemented by the European Space Agency (ESA). Its objective is to assess the ability of very low-cost satellites to carry out atmospheric measurements. PICASSO focuses on retrieving the ozone distribution in the stratosphere, the temperature profile up to the mesosphere, and the electronic density and temperature in the ionosphere.

Following its launch on a VEGA rocket in March 2020, PICASSO will fly for two years. The overall demonstration mission includes the end-to-end development of the satellite, launch, operation, and analysis of the scientific data. PICASSO follows a polar orbit at an altitude ranging from 475 to 500 km and an inclination of 98°. Its payload consists of a miniaturised hyper-spectral imager (VISION) and a four needle-like Sweeping Langmuir Probe (SLP). It utilizes four deployable solar panels with an average power generation of 8.7W, two on-board computers (OBC and PLC), and a high-performance ADCS with a pointing accuracy of around 1°.

The scientific objectives of VISION are to demonstrate the retrieval of polar and mid-latitude stratospheric ozone vertical profiles from multispectral transmittances observed in solar occultations. For SLP, the main goals are to study the ionosphere-plasmasphere coupling and aurora structures, and to monitor the density irregularities in the polar cap ionosphere.

How to cite: Baker, N., Anciaux, M., Dekemper, E., Demoulin, P., Fussen, D., Pieroux, D., and Ranvier, S.: PICASSO: a PICo-satellite for Atmospheric and Space Science Observations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7512, https://doi.org/10.5194/egusphere-egu2020-7512, 2020.

EGU2020-10377 | Displays | GI4.1

Monte Carlo simulation of polarized radiative transfer over the ocean surface

Tatiana Russkova and Konstantin Shmirko

An increasing number of remote sensing instruments measure the polarization state of electromagnetic radiation. The polarization state contains all the information about the sensing object that is available to optical measurement methods. Taking into account the polarization during the radiative transfer simulation leads to a redistribution of energy between the components of the Stokes vector, thereby introducing a correction to the scalar approximation, the value of which may be significant. This information potentially can be used to improve algorithms for removal of surface glint, underwater visibility, to improve radiative transfer retrieval methods if the polarization-sensitive sensors are employed.

A Monte Carlo polarized radiative transfer model termed MCPOLART for the ocean-atmosphere system that is able to predict the total and the polarized signals has been developed.  Since the ocean surface is not smooth, the radiation model must take into account waves that occur under the influence of wind. The Cox-Munk ocean wave slope distribution model is used in calculation of the reflection matrix of a wind-ruffled ocean surface. Sensitivity studies are conducted for various ocean-surface and atmospheric conditions, geometric schemes of lighting and observation.  

This work was supported by the Russian Science Foundation (project No. 19-77-10022).

How to cite: Russkova, T. and Shmirko, K.: Monte Carlo simulation of polarized radiative transfer over the ocean surface, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10377, https://doi.org/10.5194/egusphere-egu2020-10377, 2020.

EGU2020-13576 | Displays | GI4.1

Post-flight analysis of the aerosol impact on size distributions of warm clouds’ droplets, as determined in situ by cloud and aerosol spectrometers

Denisa Elena Moacă, Sorin Nicolae Vâjâiac, Andreea Calcan, and Valeriu Filip

The influence of aerosol on the various aspects of the atmospheric properties as well as on the energetic balance is widely recognised in the scientific community and this issue is currently subject to worldwide intense investigations. Among the multiple ways aerosol particles are impacting the atmospheric environment, their interference with the phase transformations of the atmospheric water is of particular importance. Cloud microphysics, on the other hand, is one of the key components in weather forecast and, therefore, in pursuing daily domestic activities ranging from agriculture to energy harvesting and aviation. The micro-physical processes taking place in clouds are strongly influenced by the spatiotemporal variation of the size distribution of the cloud droplets. In this context, as in situ investigations of clouds seem appropriate, one of the most useful types of instruments is casted into the generic name of Cloud and Aerosol Spectrometer (CAS) that can be mounted on specialized research aircraft. The CAS working principle relies basically on measuring the forward scattering cross section (FWSCS) of light with a certain wavelength on a cloud particle and comparing it to the FWSCS computed for pure water spheres. The eventual matching of these values leads to assigning a certain value for the measured particle’s diameter. The light wavelength is usually chosen in a range where pure water has virtually no absorption. However, atmospheric aerosol frequently mixes up with cloud droplets (starting even from the nucleation processes) and alters their optical properties. By increasing absorption and/or refractivity with respect to those of pure water, one can easily show that the FWSCS-diameter diagram changes drastically by becoming smoother and with an overall significant decrease in absolute values. This means that a CAS will systematically count “contaminated” cloud droplets in a lower range of diameters, thus distorting their real size distribution. This effect is inherently degrading the objectivity of CAS measurements and should be more pronounced when levels of sub-micrometer sized aerosol increase at the cloud altitude. The present study aims at pointing out such correlation in order to estimate the reliability of size distributions (and of the ensuing cloud microphysical properties) obtained by CAS.

How to cite: Moacă, D. E., Vâjâiac, S. N., Calcan, A., and Filip, V.: Post-flight analysis of the aerosol impact on size distributions of warm clouds’ droplets, as determined in situ by cloud and aerosol spectrometers, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13576, https://doi.org/10.5194/egusphere-egu2020-13576, 2020.

EGU2020-2372 | Displays | GI4.1

Establishing a Cyclone Generator to Study the Rotation and Advance Characteristics of Tornadoes

Yuanzhuo Zeng, Yanjie Fu, and Chenglin Lyu

The prediction of tornado trajectories has always been a crucial yet difficult problem in meteorology. In this research, an original and effective tornado simulator was designed and produced to study the travel trajectory characteristics of tornadoes through geoscience instrumentation and theoretical analysis.

First, tornado simulators designed by senior scientists were researched, and they all have one defect in common, which is failing to move freely. As a result, those tornado simulators cannot be used for studying the travel law of the tornado. Based on pioneers’ experience and real tornadoes’ features, an innovative tornado simulator that can move freely has been completed in this research. A stable wind field which bascially has the necessary characteristics of a tornado can be produced by it upon observing the wind field of the simulator.

Second, in order to research the tornadoes’ behavior in a stable external wind field, the simulator was placed floating on the water in a wind tunnel during the experiments. The experimental parameters such as the velocity of the simulator’s flow, and the velocity of the flow in the wind tunnel were carefully arranged, in order to systematically simulate different wind field conditions and observe the trajectory of the tornado simulator. Meanwhile, a tornado trajectory prediction model was made according to fluid dynamics including the Bernoulli Principle and the Precession Principle. The dynamics analyses of both real tornadoes and the simulator were carried out through formula derivation and numerical methods.

Third, by analyzing data of the trajectory of the simulator in detail through MATLAB, it was found that the offset degree was positively correlated to the rotation velocity of the tornado simulator, and negatively correlated to the wind velocity of the incoming flow, therefore verifying and enriching our model.

Fourth, the general flow function of the flow field of the simulator and tornadoes were respectively created by superposition of a flow around the symmetric cylinder function and a vortex flow function, perfecting the theoretical model. The “asymmetric flow around a cylinder” model for formula derivation in this research has been established, obtaining the numerical relationship of the velocity of the incoming flow and the simulator’s flow regarding the offset degree. The field data of the simulator and tornadoes demonstrated the validity of the theoretical assumption.

In conclusion, the Bernoulli Effect, precession effect and asymmetric flow of the tornado simulator were studied through experiments and theoretical modelling, which provided new insight and methods into the study of the trajectory of tornadoes. The experimental results conform to the theoretical assumption. This research is trail-blazing and inspiring as using mechanical devices in a wind tunnel to study the trajectory of tornadoes is unprecedented. It provides experience of how to combine engineering and geoscience in researches. The findings can help to predict the path of the tornado by monitoring the wind field of the area where the tornadoes occur, providing guidance for rescue operations.

How to cite: Zeng, Y., Fu, Y., and Lyu, C.: Establishing a Cyclone Generator to Study the Rotation and Advance Characteristics of Tornadoes, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2372, https://doi.org/10.5194/egusphere-egu2020-2372, 2020.

EGU2020-9194 | Displays | GI4.1

Study of seasonal and short-term temperature variations in the middle atmosphere using cosmic muons

Matias Tramontini, Marina Rosas-Carbajal, Christophe Nussbaum, Dominique Gibert, and Jacques Marteau

In the last decades, large particle-physics experiments have shown that muon rate variations detected in underground laboratories are sensitive to regional, middle-atmosphere temperature variations. Therefore, muon measurements may be used to study middle-atmosphere dynamics, including short-term phenomena such as Sudden Stratospheric Warmings. In this work we use a portable muon detector conceived for geosciences applications. We study seasonal and short-term variations in the middle-atmosphere’s temperature by analyzing a year of continuous muon measurements at the Mont Terri underground rock laboratory. This site is located in the Jura Mountains in north-western Switzerland, at a depth of ~300 meters below the Earth's surface. We observe a direct correlation between middle‐atmosphere seasonal temperature variations and muon rate. Muon rate variations are also sensitive to the abnormal atmosphere heating in January-February 2017, associated to a major Sudden Stratospheric Warming that in a few days increased the zonal mean temperature in the polar region by more than 20 K. We estimate the effective temperature coefficient for our particular case and found that it agrees with theoretical models and with those calculated from large neutrino experiments under comparable conditions. Finally, we discuss the implications of our observations for the Atmospheric Sciences community.

How to cite: Tramontini, M., Rosas-Carbajal, M., Nussbaum, C., Gibert, D., and Marteau, J.: Study of seasonal and short-term temperature variations in the middle atmosphere using cosmic muons, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9194, https://doi.org/10.5194/egusphere-egu2020-9194, 2020.

EGU2020-579 | Displays | GI4.1

A database of Black Sea beaches

Tahsin Görmüş, Berna Ayat, and Burak Aydoğan

Beaches are not only one of the most beautiful natural entities the world coasts, they are also habitat for various species of living creatures, barrier against coastal hazards. Their conservation is crucially important, yet the efforts seem deficient. Geographic information systems are great tools towards this aim by incorporating coastal data and visually representing them. In this study, a database for all the beaches along the Black Sea coastline is created to help the efforts on marine conservation and coastal management. 1553 beaches have been digitized as polygons using satellite images between 2013 and 2016 covering the entire Black Sea coast. Geometric properties such as area, perimeter, width, central coordinates, UTM zone, shoreline length, and bound orientation are obtained through different data collection techniques. Information related to natural properties such as estuaries, coastal structures, and settlement densities have been gathered. Results indicated that Black Sea beaches are relatively narrow. Most of them are either experienced erosion or have a vulnerability to erosion. Among all 1553 beaches, only 28 beaches have an average width wider than 100 m. In the basin, the average width of the beaches is 26.04 m, the average beach area is 70384.2 m2 and the total beach shoreline length is 2116.12 km, which covers 43% of the Black Sea coastline. The mean slope values of the beaches with a maximum width of greater than 100 m are calculated using ASTER Digital Elevation Model v2. According to this analysis, the mean slope of these 164 beaches is 7.28 degrees. An additional analysis is performed by creating a different layer for the South-western part of the basin, from approximately 5 years older satellite images. This analysis showed that, even in the short-term, beaches can experience significant area loss reaching up to 50% in a relatively high wave climate such as exists in the South-western part.

How to cite: Görmüş, T., Ayat, B., and Aydoğan, B.: A database of Black Sea beaches, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-579, https://doi.org/10.5194/egusphere-egu2020-579, 2020.

GI4.2 – Lidar remote sensing of the atmosphere

EGU2020-10310 | Displays | GI4.2 | Highlight

MicroPulse DIAL (MPD) ground-based network for Thermodynamic Profiling in the Lower Troposphere

Scott Spuler, Robert Stillwell, Matt Hayman, Tammy Weckwerth, and Kevin Repasky

The National Center for Atmospheric Research and Montana State University have developed a 5-unit ground-based test network of MicroPulse Differential Absorption Lidar (MPD) instruments to continuously measure high-vertical-resolution water vapor profiles in the lower atmosphere. These diode-laser-based instruments are accurate, low-cost, operate unattended, do not require external calibration, and eye-safe – all key features to enable larger 'national-scale' networks needed to characterize atmospheric moisture variability, which influences important processes related to weather and climate.  Enhancements to the water vapor MPD architecture have been recently developed that enable quantitative aerosol measurements and atmospheric temperature profiling by simultaneously measuring O2 absorption and aerosol backscatter ratio. This combination of measurements allows for the first DIAL measurements of atmospheric temperature with useful accuracy. The MPD has been demonstrated to provide continuous, range-resolved measurements of atmospheric thermodynamic variables, water vapor and temperature, and quantitative measurements of aerosol scattering from a high spectral resolution (HSRL) channel.  Thus, a network of these instruments shows promise to provide atmospheric profiling capabilities needed by both the climate and weather forecasting research communities.

How to cite: Spuler, S., Stillwell, R., Hayman, M., Weckwerth, T., and Repasky, K.: MicroPulse DIAL (MPD) ground-based network for Thermodynamic Profiling in the Lower Troposphere, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10310, https://doi.org/10.5194/egusphere-egu2020-10310, 2020.

EGU2020-12164 | Displays | GI4.2

Compact Operational Tropospheric Water Vapor and Temperature Raman Lidar with Turbulence Resolution

Diego Lange Vega, Andreas Behrendt, and Volker Wulfmeyer

Here we present the new Atmospheric Raman Temperature and Humidity Sounder (ARTHUS), an exceptional tool for observations in the atmospheric boundary layer during daytime and nighttime with a very short latency. ARTHUS measurements resolve the strength of the inversion layer at the planetary boundary layer top, elevated lids in the free troposphere during daytime and nighttime, and turbulent fluctuations in water vapor and temperature, simultaneously, also during daytime.

The observation of atmospheric moisture and temperature profiles is essential for the understanding and prediction of earth system processes. These are fundamental components of the global and regional energy and water cycles, they determine the radiative transfer through the atmosphere, and are critical for the clouds formation and precipitation. Also, it is expected that the assimilation of high-quality, lower tropospheric WV and T profiles will result in a considerable improvement of the skill of weather forecast models particularly with respect to extreme events.

Very stable and reliable performance was demonstrably achieved during more than 2500 hours of operations time experiencing a huge variety of weather conditions. ARTHUS provides temperature profiles with resolutions of 10-60 s and 7.5-100 m vertically in the lower free troposphere. During daytime, the statistical uncertainty of the WV mixing ratio is <2 % in the lower troposphere for resolutions of 5 minutes and 100 m. Temperature statistical uncertainty is <0.5 K even up to the middle troposphere. ARTHUS fulfills the stringent WMO breakthrough requirements on nowcasting and very short-range forecasting.

This performance serves very well the next generation of very fast rapid-update-cycle data assimilation systems. Ground-based stations and networks can be set up or extended for climate monitoring, verification of weather, climate and earth system models, data assimilation for improving weather forecasts.

How to cite: Lange Vega, D., Behrendt, A., and Wulfmeyer, V.: Compact Operational Tropospheric Water Vapor and Temperature Raman Lidar with Turbulence Resolution, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12164, https://doi.org/10.5194/egusphere-egu2020-12164, 2020.

EGU2020-17672 | Displays | GI4.2

Relative humidity fields in the Annecy Alpine valley observed by Ro-Vibrational Raman lidar in the framework of L-WAIVE

Alexandre Baron, Patrick Chazette, and Julien Totems

In June 2019, the Lacustrine-Water vApor Isotope inVentory Experiment (L-WAIVE) has been performed in the southern part of the Annecy lake (45°47' N, 6°12' E). The field campaign motivation is to bring a better comprehension on the evaporation processes above Alpine lakes influencing, along with orography, the complex atmospheric structuration. In particular, this two-week field campaign has involved the meteorological Raman lidar WALI (Weather and Aerosol LIdar). An ultra-light aircraft carrying a meteorological probe and a particle sizer performed several vertical profiles above the ground-based Raman lidar with a vertical resolution between 50 and 100 m for flights operated from the ground level (~0.5 km above the mean sea level (AMSL)) and ~4 km AMSL.

This setup is an opportunity to experimentally assess the instrumental errors on both the temperature and the water vapour mixing ratio profiles derived from the ground-based lidar. The methodology used to calculate the error budget will be presented. It will take into account the different types of statistical noises associated with the lidar measurement. In particular, the importance of the spectral filtration in the accuracy of the results will be discussed. The uncertainties associated with the lidar calibration procedure will be quantified. Following this detailed study, the first results of relative humidity will be presented, taking into account the associated error bars.

How to cite: Baron, A., Chazette, P., and Totems, J.: Relative humidity fields in the Annecy Alpine valley observed by Ro-Vibrational Raman lidar in the framework of L-WAIVE, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17672, https://doi.org/10.5194/egusphere-egu2020-17672, 2020.

Tropospheric aerosols  are a fundamental component of the Earth’s radiation budget. In order to properly estimate their direct and indirect effect, accurate measurements of aerosol size and microphysical properties are required.A limited number of techniques are presently available and capable to provide these measurements.

Multi-wavelength Raman lidars Raman lidars have strong potential. However,theireffectiveness and reliability of need to be assessed and verified against independent measurements.

This abstract reports measurements that were carried out by the Raman lidar system BASIL in the frame of the Hydrological Cycle in the Mediterranean Experiment – Special Observation Period 1 (HyMeX-SOP1).The considered dataset represents a good opportunity to verify the quality of retrievals in terms of size and microphysical properties obtained from multi-wavelength Raman lidars.

A specific case study was selected revealing the presence of variable aerosol properties at different altitudes. Specifically, Raman lidar measurements on 02 October 2012 show the presence of two distinct aerosol layers, a lower one extending up to ~3 km and an upper one extending from 3.5 km to 4.7 km. Aerosol and size microphysical properties are determined from multi-wavelength measurements of particle backscattering and extinction profiles based on the application of  a retrieval scheme which employs Tikhonov’s inversion with regularization. Inversion results suggest a size distribution with the presence, in both the lower and upper aerosol layer, of two particle modes (a fine mode, with a radius of ~0.2 mm, and a coarse mode, with radii in the range 2-4 mm), volume concentration values of 2-4 mm3cm-3and effective radii in the  range 0.2-0.6 mm.

This effort benefited from the dedicated flights of the French research aircraft ATR42, equipped with a variety of in situ sensors for measuring aerosol/cloud size and microphysical properties. Aerosol size and microphysical properties retrieved from multi-wavelength Raman lidar measurements were compared with simultaneous and co-located in-situ measurements.

How to cite: De Rosa, B., Di Girolamo, P., and Summa, D.: Determination of aerosol size and microphiysical proprierties based on multi-wavelength raman lidar measurements in the framework of HyMeX-SOP1, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17218, https://doi.org/10.5194/egusphere-egu2020-17218, 2020.

EGU2020-20573 | Displays | GI4.2

NASA new V3 Micro-Pulse Lidar Network Rain and Snow masking algorithm application: Aerosol wet deposition.

Simone Lolli, Gemine Vivone, Ellsworth J. Welton, Jasper R. Lewis, Micheal Sicard, Adolfo Comeron, and Gelsomina Pappalardo

In this study we illustrate the development of a rain and snow masking algorithm applied to the National  Aeronautics and Space Administration (NASA) Micro-Pulse lidar network (MPLNET) observations. The algorithm, once operationally implemented, will deliver in Near Real Time (latency <1.5 hr) the rain and snow masking variables. The products will be publicly available on MPLNET website as part of the new Version 3 release. The methodology, based on image processing techniques, can detect only light to moderate rainfall and snowfall events (defined by intensity and duration) becasue of laser attenuation.  The main underlying technique consists in applying the morphological filters on the volume depolarization ratio composite image to identify  squared shapes under the cloud bases that corresponding to the precipitation. Results from the algorithm, besides filling a gap in precipitation and virga detection by radars, are of particular interest for the scientific community because will help to fully characterize the aerosol cycle, from emission to deposition, as precipitation is a crucial meteorological phenomena accelerating the atmospheric aerosol removal through the wet scavenging effect. As an example, in this study we prove, for the first time to our knowledge, how rain detection from ground-based lidar observations are effective in showing a strong negative correlation between the Aerosol Optical Depth (AOD) and precipitation.

How to cite: Lolli, S., Vivone, G., Welton, E. J., Lewis, J. R., Sicard, M., Comeron, A., and Pappalardo, G.: NASA new V3 Micro-Pulse Lidar Network Rain and Snow masking algorithm application: Aerosol wet deposition., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20573, https://doi.org/10.5194/egusphere-egu2020-20573, 2020.

EGU2020-2915 | Displays | GI4.2

Removal of range uncertainty of CW Wind Lidar by frequency modulation.

Gerhard Peters and Piet Markmann

Frequency Modulation (FM) is a well-known technology but was never used in Continuous Wave (CW) Wind Lidars. The reason is because range and velocity can only be resolved for single hard targets like vehicles but not for dispersed targets like atmospheric aerosol. Here we present a FMCW system that uses the established focusing method for ranging and in addition a frequency modulated transmit signal. The origin of the scattered radiation is localized by focusing in a limited measuring volume. Because of this – by applying FM – the unavoidable range-velocity ambiguity of CW Wind Lidars can be resolved similarly as for hard targets. This is particularly important in conditions with fog or low hanging clouds (coastal or mountainous areas) or distant moving obstacles behind the measuring volume, or generally spoken in cases with strong gradients of the backscatter cross section. While out-of-focus contributions is a well-known concern of CW Lidar, we will show examples from FMCW field measurements first time revealing quantitatively the range uncertainty based on focus distance. Not surprisingly this uncertainty increases with height range, where the focus becomes less well-defined. Furthermore, the FMCW Wind Lidar allows also to correct uncertainties of mechanical focus distance setting. This is also mainly important at larger ranges where the focus distance becomes very sensitive to mechanical tolerances. Moreover, auxiliary measurements of wind direction, that are needed by CW systems for removing the sign-ambiguity of velocity, are obsolete, and there is no lower threshold of measurable windspeed. As a consequence wind measurements are feasible in street canyons, forest clearings and any other environment with strong vertical gradients.

How to cite: Peters, G. and Markmann, P.: Removal of range uncertainty of CW Wind Lidar by frequency modulation., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2915, https://doi.org/10.5194/egusphere-egu2020-2915, 2020.

EGU2020-17951 | Displays | GI4.2

Optical and geometrical properties of Arctic clouds over northern Finland during PaCE campaign in 2019

Xiaoxia Shang, Mika Komppula, Elina Giannakaki, Stephanie Bohlmann, Maria Filioglou, and David Brus

In the Arctic areas the influence of climate change is being felt at a higher degree than elsewhere. Enabling a better understanding of the environment in region is of high importance. Clouds play a significant role in the energy budget and the hydrological cycle of the Earth’s atmosphere system. In order to provide insights into Arctic cloud processes for Arctic cloud-climate studies, the field campaign PaCE (Pallas Cloud Experiment) was organized during autumn and winter 2019; the campaign was focusing on aerosol and cloud vertical profiling using in-situ and remote sensing techniques.

During the campaign, a ground-based multi-wavelength Raman polarization lidar PollyXT performed continuous measurements from September to December 2019, at the Kenttärova station (N 67°59’14”, E 24°14’35”, 347 m above sea level) at Pallas, in the northern Finland. This is a background station surrounded by the forest, where the atmosphere is quite clean. Cloud vertical structures and optical properties have been determined from lidar analysis. During day-time, the Klett method is applied to retrieve the vertical profiles of cloud extinction and backscatter coefficient at three wavelengths (355 nm, 532 nm and 1064 nm). During night-time, the standard Raman method is used to provide additional lidar ratio profiles at 355 nm and 532 nm. The actual linear depolarization ratio at two wavelengths (355 nm and 532 nm) are also retrieved. With water vapor channel at 407 nm, the relative humidity profile are also available for received signal with good signal-to-noise ratio. The combined use of near and far field telescopes provides reliable vertical profiles of optical properties from 0.25 km to 10 km above ground level. The temperature and thickness dependencies on optical properties have also been studied in detail. Geometrical properties of cloud are retrieved using both lidar and ceilometer, statistic values of cloud height, and thickness are shown.

How to cite: Shang, X., Komppula, M., Giannakaki, E., Bohlmann, S., Filioglou, M., and Brus, D.: Optical and geometrical properties of Arctic clouds over northern Finland during PaCE campaign in 2019, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17951, https://doi.org/10.5194/egusphere-egu2020-17951, 2020.

EGU2020-2207 | Displays | GI4.2

BLISS: a backscattering space-borne LIDAR simulator

Roseline Schmisser, Jordi Chinaud, and Philippe Galaup

Long-term data on clouds and aerosols are of critical importance to accurately model climate change. In particular, CALIPSO-like LIDAR missions give access to data on clouds height, distribution, optical depths… as well as information on aerosol types and concentration.

In this context, BLISS (Backscattering Lidar Signal Simulator) has been developed by CNES and Thales Services to simulate the return signal received by a backscattering space-borne LIDAR and the associated data processing (level 0 to level 2), in order to perform mission dimensioning studies as well as sensitivity studies on instrument or geophysical parameters. Given a specific input scene, it provides the vertical profiles of clouds and aerosol actually in the atmosphere as seen by the LIDAR and can also provide a profile of the first few meters inside the oceans – if any – thus representing the backscattering of light by particles as plankton.  It has already especially been used on MESCAL phase 0 and its outputs have been compared with other existing LIDAR codes (like the one developed by NASA LARC).

BLISS user interface, its different modules and an associated end-to-end simulation will be presented.

How to cite: Schmisser, R., Chinaud, J., and Galaup, P.: BLISS: a backscattering space-borne LIDAR simulator, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2207, https://doi.org/10.5194/egusphere-egu2020-2207, 2020.

Dust lidar ratios are retrieved by a synergetic use of CALIOP and MODIS products for 5 years from 2007 to 2011. The CALIOP level 1 total attenuated backscatter data is used for the retrieval and the CALIOP level 2 aerosol profile product is used to determine dust layers. Quality assured (QA > 1 for dark target ocean, QA = 3 for deep blue land) aerosol optical depth (AOD) data from the MODIS level 2 aerosol product is used as constraint. MODIS AOD retrievals and CALIOP attenuated backscatter profiles closer than 10 km from the center of MODIS pixel are defined as collocated measurements. Clouds are screened out for both CALIOP and MODIS. The retrieval is performed for the whole column of the atmosphere from 30 km to the surface adopting a constant lidar ratio of 30 sr for aerosols of clear air above the detected layers. The retrieved dust lidar ratios show a log-normal distribution with mean (median) values of 39.5 ± 16.8 (38.1) sr and 46.6 ± 36.3 (39.2) sr for ocean and land, respectively. The mean values are comparable to the value of 44 sr currently used in the CALIOP level 2 aerosol algorithm but the median values are relatively lower. There is a distinct regional variation in the retrieved dust lidar ratios. Dust lidar ratio is larger for the Saharan Desert (49.5 ± 36.8 sr) than the Arabian Desert (42.5 ± 26.2 sr), which is consistent with many previous studies. Dust aerosols transported to the Mediterranean Sea (44.4 ± 15.9 sr), Mid Atlantic (40.3 ± 12.4 sr) and Arabian Sea (37.5 ± 12.1 sr) show lower values compared with their source regions. An aging process of the long-range transported dust to remote ocean may be responsible for low lidar ratios. Dust lidar ratio over ocean in East Asia is 41.8 ± 27.6 sr is comparable with previous studies. Over Taklamakan and Gobi Deserts region the retrieved dust lidar ratios (35.5 ± 31.1 sr) show low values but still comparable with previous studies. Dust lidar ratios for Australia (35.4 ± 34.4 sr) are also relatively low compared with other regions. Although the mean AOD difference between CALIOP and MODIS is small (close to zero), the distribution of the AOD difference shows that the CALIOP AOD is biased low. However, when including clear air AOD for CALIOP, AODs from the two sensors become more comparable. A conclusion that can be drawn from this is that retrieving only for the detected layers in the CALIOP algorithm is one of the major reasons for lower AODs for CALIOP than MODIS. Lidar ratios retrieved in this study are strongly affected by MODIS AOD, because it is used as a constraint for the retrieval.

How to cite: Kim, S.-W., Kim, M.-H., and Omar, A.: Dust lidar ratios retrieved from the space-borne CALIOP measurements using the MODIS AOD as a constraint, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2279, https://doi.org/10.5194/egusphere-egu2020-2279, 2020.

EGU2020-4652 | Displays | GI4.2

Mesoscale variability of the aerosol distribution as determined from ceilometer measurements

Matthias Wiegner, Alexander Geiß, Ina Mattis, Fred Meier, and Thomas Ruhtz

The spatial distribution of aerosol particles is relevant for studies on the radiation budget, for the verification of chemistry transport models, or for air quality studies just to name a few. As the distribution is highly variable the requirements to measurements are very demanding. As a consequence it is often assumed that the aerosol distribution is "relatively homogeneous", i.e., measurements at one site are representative for a larger area.

By exploiting 2 years of measurements from 12 ceilometers located in the area of Munich and Berlin, Germany, we have investigated the spatial differences between locations separated between 3~km and 50~km. For this purpose we have used the mixing layer height (MLH), a quantity often used when the vertical aerosol distribution should be described by a single parameter. The MLH was determined by the COBOLT-algorithm (Geiß et al., 2017). It was found that the MLHs at different locations inside the two cities are highly correlated and agree within a few tens of meters. However, the maximum extension of the mixing layer from April to September was found to be significantly larger in Berlin compared to Munich.


Geiß, A., Wiegner, M., Bonn, B., Schäfer, K., Forkel, R., von Schneidemesser, E., Münkel, C., Chan, K. L., and Nothard, R. (2017): Mixing layer height as an indicator for urban air quality?  Atmos. Meas. Tech., 10, 2969-2988, https://doi.org/10.5194/amt-10-2969-2017, 2017.

How to cite: Wiegner, M., Geiß, A., Mattis, I., Meier, F., and Ruhtz, T.: Mesoscale variability of the aerosol distribution as determined from ceilometer measurements, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4652, https://doi.org/10.5194/egusphere-egu2020-4652, 2020.

EGU2020-7637 | Displays | GI4.2

Top-down lidar characterization of exceptional dust transport event above the Annecy lake during L-WAIVE in June 2019

Julien Totems, Patrick Chazette, Alexandre Baron, and Elsa Dieudonné

The L-Waive campaign took place over the Annecy lake in France in June 2019. In an effort to better understand the atmospheric structure and the water cycle over lakes, it involved an airborne Rayleigh-Mie lidar, ground-based Raman & wind lidars, as well as airborne measurements of water vapor and its isotopes, and aerosol particle size distribution.

This represented a unique opportunity to study the vertical structuring of the troposphere, which is poorly documented in mountainous regions and particularly in the Alpine valleys. Regular radio-soundings are generally not representative of the low atmospheric layers encountered above the valleys, which are influenced by relief winds. Lidar observations in Alpine valleys have been made in the past using Rayleigh-Mie instrumentation, but during L-WAIVE the ground-based Raman lidar WALI also measured the meteorological parameters of water vapour and temperature. The airborne lidar ALIAS carried by an ultra-lght aircraft complemented aerosol measurements, in a coupled top-down inversion approach, highlighting the influence of mountains on different vertical and horizontal scales.

This setup was operational when an exceptional dust transport event overpassed south-eastern France on June 14th, 2019. The origin of this event was shown by HYSPLIT back-trajectories and thermal anomalies computed from SEVIRI as laying in the Grand Erg Occidental, Algeria. An aerosol optical thickness up to 0.8 at 355 nm was measured by the lidar on this occasion, and the instrumental lidar synergy allows to completely characterize the dust plumes in terms of particle extinction, depolarization, relative humidity, and airmass velocities and potential temperature. The dust-perturbated atmosphere will be compared to the background situation where only pollution aerosols are present. The effect of the mountain aerology on the transport will thus be discussed.

How to cite: Totems, J., Chazette, P., Baron, A., and Dieudonné, E.: Top-down lidar characterization of exceptional dust transport event above the Annecy lake during L-WAIVE in June 2019, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7637, https://doi.org/10.5194/egusphere-egu2020-7637, 2020.

The South China Sea is the third largest inland sea in the world, with unique geographical and climatic conditions, and great economic importance. Observation of aerosols over this region is needed to understand their role in cloud, radiation, and ocean primary production. While the optical properties of marine aerosols over the South China Sea have been studied using solar photometers, there are no lidar studies for this region that the authors know of in publicly accessible scientific literature.

To test the viability of shipborne lidar for aerosol measurement over the South China Sea, a shipborne micro-pulse lidar (Mini-MPL) was used to measure aerosol extinction coefficient in the northern region of the South China Sea over a period of one month from 9th August to 7th September, 2016, along the cruise path of a research vessel. The measurements were inverted to obtain vertical profiles of aerosol extinction coefficient, depolarization ratio, and atmospheric boundary layer height using Mie Theory and the Fernald method. Aerosols were found to be concentrated low in the atmosphere, with more than 73% of total extinction below 2 km and almost no aerosol above 3.5 km. Maximum extinction values in coastal areas were generally about double of values in offshore areas. The aerosol concentration was lower in the northwest side of the South China Sea compared to the northeast side, a pattern that may due to advection by the prevailing summer southwesterly winds. Vertical profiles and back-trajectory calculations indicated vertical and horizontal layering of aerosols from different terrestrial sources. The mean depolarization ratio of the aerosols along the cruise was 0.042. Atmospheric boundary layer height along the cruise was average 653.2 m, with a diurnal cycle reaching its mean maximum of 1041.2 m at 12:00, and its mean minimum of 450.0 m at 20:00.

How to cite: Li, Y.: Micro-pulse Lidar Measurements in South China Sea Expedition , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12642, https://doi.org/10.5194/egusphere-egu2020-12642, 2020.

EGU2020-19164 | Displays | GI4.2

Comparing Halo Doppler lidar depolarization ratio with PollyXT

Ville Vakkari, Ewan O'Connor, Holger Baars, and Johannes Bühl

Depolarization ratio is highly valuable in lidar-based aerosol classification and can be used to quantify the contributions of different aerosol types to elevated layers [1]. Typically, aerosol particle depolarization ratio is determined at relatively short wavelengths of 355 nm and/or 532 nm, though some multi-wavelength case studies including 1064 nm have shown strong spectral dependency [2,3]. Here, we demonstrate that Halo Photonics Stream Line Doppler lidars can be used to retrieve aerosol particle depolarization ratio at 1.5 µm wavelength.

 

We utilize measurements in April-May 2017 at Limassol, Cyprus to compare the Halo 1.5 µm aerosol particle depolarization ratio with Polly XT aerosol particle depolarization ratio. Recently developed post-processing [4] enables retrieving weak signals (as low as -32 dB) with the Halo Doppler lidar. At Limassol, we were able to determine particle depolarization ratio for several cases of mineral dust up to 3 km above ground. Generally, particle depolarization ratio for mineral dust at 1.5 µm appears higher than at shorter wavelengths of 355 nm and 532 nm retrieved by Polly XT. Overall, our results indicate that Halo Doppler lidars can add another wavelength at 1.5 µm to studies on the spectral dependency of aerosol depolarization ratio, at least in the lowest 2-3 km above ground.

 

[1] Mamouri, R.-E. and Ansmann, A.: Potential of polarization/Raman lidar to separate fine dust, coarse dust, maritime, and anthropogenic aerosol profiles, Atmos. Meas. Tech., 10, 3403-3427, https://doi.org/10.5194/amt-10-3403-2017, 2017.

[2] Burton, S. P., Hair, J. W., Kahnert, M., Ferrare, R. A., Hostetler, C. A., Cook, A. L., Harper, D. B., Berkoff, T. A., Seaman, S. T., Collins, J. E., Fenn, M. A. and Rogers, R. R.: Observations of the spectral dependence of linear particle depolarization ratio of aerosols using NASA Langley airborne High Spectral Resolution Lidar, Atmos. Chem. Phys., 15, 13453–13473, doi:10.5194/acp-15-13453-2015, 2015.

[3] Haarig, M., Ansmann, A., Baars, H., Jimenez, C., Veselovskii, I., Engelmann, R. and Althausen, D.: Depolarization and lidar ratios at 355, 532, and 1064 nm and microphysical properties of aged tropospheric and stratospheric Canadian wildfire smoke, Atmos. Chem. Phys., 18, 11847–11861, doi:10.5194/acp-18-11847-2018, 2018.

[4] Vakkari, V., Manninen, A. J., O’Connor, E. J., Schween, J. H., van Zyl, P. G. and Marinou, E.: A novel post-processing algorithm for Halo Doppler lidars, Atmos. Meas. Tech., 12(2), 839–852, doi:10.5194/amt-12-839-2019, 2019.

How to cite: Vakkari, V., O'Connor, E., Baars, H., and Bühl, J.: Comparing Halo Doppler lidar depolarization ratio with PollyXT, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19164, https://doi.org/10.5194/egusphere-egu2020-19164, 2020.

EGU2020-4905 | Displays | GI4.2

Aerosol layering in free troposphere, its impact on modification of the UV irradiation over industrial site in southern Poland

Aleksander Pietruczuk, Janusz Krzyscin, Artur Szkop, and Alnilam Fernandes

Ceilometers are effective instruments to study atmospheric profiles. They are primarily designed to study cloud base height however are widely used to study aerosol optical properties profiles, aerosol backscatter or extinction coefficients or just atmospheric layering. In this work we utilized statistics of aerosol layers in free troposphere to explain differences between measured and modelled UV radiation at Raciborz station in southern Poland.

Raciborz is a town in southern Poland, close to the Czech Republic border. This area is affected by local urban and industrial pollutions from urban area of Silesia in South Western Poland and North Eastern Czech Republic. Remote locations of aerosols may also play important role in UV radiation modification. The observatory in Raciborz is equipped with CHM-15k Nimbus ceilometer, triple Sun-Sky-Lunar CIMEL ceilometer, and Kipp & Zonen UVS-E-T biometer.

Series of erythema dose rates were compared to that modelled by Tropospheric Ultraviolet-Visible (TUV) radiation transfer model. We used satellite (OMI) ozone, aerosol columnar properties (optical thickness at 340 nm, Angstrom exponent for 340-440nm range as well as single scattering albedo and asymmetry parameter at 440 nm) measured by CIMEL photometer as model input values. The model/observations differences are within +/- 5% range for 90% of measured doses during cloud free conditions. The median of model/observations ratio differences is 0.994. To explain revealed ratio variability a statistical, regression model was developed. A random forest approach applied to normalized erythema doses explained about 52% of model/observations ratio differences by aerosol characteristics in free troposphere.

Aerosol characteristics provided as statistical model input are: mean altitude of aerosol’s layer base and top, geometrical thickness of all layers and sum of aerosol layer backscatter intensity (in arbitral units) normalized by layer geometrical thickness. Aerosol layers are found throughout the year with the highest frequency in August (about 80%  days with at least one layer) and the lowest in November (about 10% days). For days with layers, the mean number of  the layers per day is less variable usually 2-3 layers in one day. The mean depth of the layer  is  larger in summer (1.3 km) than in winter (0.8 km) but the life time of the layer is similar of about 7-8 hours in both periods.

Acknowledgements

This work was supported by Polish National Science Center under grant no. 2017/25/B/ST10/01650.

How to cite: Pietruczuk, A., Krzyscin, J., Szkop, A., and Fernandes, A.: Aerosol layering in free troposphere, its impact on modification of the UV irradiation over industrial site in southern Poland , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4905, https://doi.org/10.5194/egusphere-egu2020-4905, 2020.

EGU2020-5949 | Displays | GI4.2

The instrument for lidar infrared remote measurement of industrial pollution

Viacheslav Meshcherinov, Maxim Spiridonov, Viktor Kazakov, Iskander Gazizov, and Alexander Rodin

Remote monitoring of industrial emissions into the atmosphere, the hazardous gases near landfills and incinerators, monitoring the presence of gas leaks in manufactures today play a huge role for human being. And this role will increase in the near future, because of aggravated ecological problems, business interests etc.

We present an instrument concept for lidar monitoring of industrial atmospheric pollution, based on the commonly used technique for tunable diode laser spectroscopy (TDLS), termed wavelength modulation spectroscopy (WMS). This instrument is being developed to determine the presence of technogenic pollution of atmospheric air in concentrations that pose a danger to nature, as well as human life and health. At the first stage, methane was chosen as the object of interest.

For remote measurement of atmospheric impurities, we propose to use a near-infrared diode laser (DL) operating in continuous mode with sinusoidal modulation of the injection current with a frequency of ~100 kHz. In the absence of molecules absorbing laser radiation, the photodetector detects radiation only at the modulation frequency f. In the presence of absorbing molecules, a signal appears at higher harmonics (2f, 3f). If the laser radiation is tuned to the center of the absorption line and modulated in the vicinity of this value, then the received signal at the first harmonic 1f is proportional to the total intensity of the detected radiation, and the 2f signal is proportional to the intensity absorbed by the molecules of the measured gas. Thus, the amplitude ratio of 2f signal and 1f signal characterizes the absorption of the measured gas and allows calculating of this gas concentration. Furthermore in remote measurements of laser radiation scattered from the surface, the total intensity of the detected radiation can vary by an order of magnitude, therefore, normalization of the 2f signal to the 1f signal is necessary.

The correct operation of this technique require that the radiation frequency of the DL should be stabilized at the center of the absorbing line with high accuracy: ~1% of the absorption line width, which at atmospheric pressure is ~10-3 cm-1. Such high stability of the laser radiation frequency is achievable using the 3f signal, which passes through zero in the center of the line.

During the implementation of the project a compact and lightweight instrument, that can be installed on the unmanned aerial vehicles (UAVs) to control the emission of harmful gases at industrial sites, landfills, will be created. Currently, such instrument using other operation algorithms have a mass of 10-20 kg and are usually installed on manned helicopters. The installation of such instrument on the UAV will greatly simplify and reduce the cost of industrial pollution monitoring. First tests of our instrument are planned on the second half of 2020.

 

Acknowledgments

This work has been supported by the Russian Foundation for Basic Research [Grant No.18-29-24204].

How to cite: Meshcherinov, V., Spiridonov, M., Kazakov, V., Gazizov, I., and Rodin, A.: The instrument for lidar infrared remote measurement of industrial pollution, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5949, https://doi.org/10.5194/egusphere-egu2020-5949, 2020.

EGU2020-20917 | Displays | GI4.2

Boundary layer height determination from lidar for improving air pollution episode modeling: development of new algorithm and evaluation

Ting Yang, zifa wang, wei zhang, Alex Gbaguidi, and Nobuo Sugimoto

Predicting air pollution events in the low atmosphere over megacities requires a thorough understanding of the tropospheric dynamics and chemical processes, involving, notably, continuous and accurate determination of the boundary layer height (BLH). Through intensive observations experimented over Beijing (China) and an exhaustive evaluation of existing algorithms applied to the BLH determination, persistent critical limitations are noticed, in particular during polluted episodes. Basically, under weak thermal convection with high aerosol loading, none of the retrieval algorithms is able to fully capture the diurnal cycle of the BLH due to insufficient vertical mixing of pollutants in the boundary layer associated with the impact of gravity waves on the tropospheric structure. Consequently, a new approach based on gravity wave theory (the cubic root gradient method: CRGM) is developed to overcome such weakness and accurately reproduce the fluctuations of the BLH under various atmospheric pollution conditions. Comprehensive evaluation of CRGM highlights its high performance in determining BLH from lidar. In comparison with the existing retrieval algorithms, CRGM potentially reduces related computational uncertainties and errors from BLH determination (strong increase of correlation coefficient from 0.44 to 0.91 and significant decreases of the root mean square error from 643 to 142 m). Such a newly developed technique is undoubtedly expected to contribute to improving the accuracy of air quality modeling and forecasting systems.

How to cite: Yang, T., wang, Z., zhang, W., Gbaguidi, A., and Sugimoto, N.: Boundary layer height determination from lidar for improving air pollution episode modeling: development of new algorithm and evaluation, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20917, https://doi.org/10.5194/egusphere-egu2020-20917, 2020.

EGU2020-7191 | Displays | GI4.2 | Highlight

Lidar measurements characterizing the thermodynamic and dynamic structure of the boundary layer up to the turbulence scale

Andreas Behrendt, Diego Lange, Florian Späth, Shravan Kumar Muppa, Simon Metzendorf, Christoph Senff, and Volker Wulfmeyer

One weakness of today's weather and climate models is the inaccurate representation and parameterization of the boundary layer processes and land-atmosphere (L-A) feedback. In order to investigate these processes, scanning lidar systems allow the observation not only of wind with Doppler lidar but also of humidity and temperature. It is expected that advances in the understanding of LA feedback and boundary-layer exchange will significantly contribute to better simulations of clouds and precipitation on all temporal and spatial scales.

In this contribution, we present recent thermodynamic measurements in the surface layer, atmospheric boundary layer and free troposphere with very high resolution achieved during several field campaigns like the Land-Atmosphere Feedback Experiment (LAFE) in 2017, ScaleX in 2019, EUREC4A in 2020, and at the Land-Atmosphere Feedback Observatory (LAFO) in 2020.

University of Hohenheim (UHOH) operates besides two scanning Doppler lidars (HALO Photonics StreamlineXR), three lidars for thermodynamic profiling which have been developed within the last 15 years by the Institute of Physics and Meteorology itself. These are two scanning lidar systems which are semi-automated and a fully-automated vertical pointing lidar system.

The water vapor differential absorption lidar (DIAL) of UHOH is a mobile system with a laser power of up to 10 W at 818 nm with a pulse repetition rate of 300 Hz. The receiver consists of an 80-cm telescope. The raw resolution of the atmospheric backscatter signals is 15 m and single shot. The resolution of the data product, the water vapor number density or absolute humidity, is typically 1 to 10 s and 40 to 200 m.

The UHOH Rotational Raman Lidar measures temperature and water vapor mixing ratio. Also this system is mobile. So far, we used as transmitter a flash-lamp-pumped Nd:YAG laser with 12 W at 355 nm at 50 Hz. This laser is currently being exchanged against a similar laser with 20 W at the same pulse repetition frequency. The light backscattered from the atmosphere is received with a 40 cm telescope. Four channels detect the elastic backscatter signal, two rotational Raman signals, and the water vapor Raman signal. The signal intensities are detected in analog and photon counting mode with raw resolutions of 7.5 m and 10 s. Typical resolutions of the data products are 100 m and 10 s.

A compact and automated further development of this system, ARTHUS for Atmospheric Raman Temperature and Humidity Sounder, uses already this powerful diode-pumped laser transmitter (20 W at 355 nm, 200 Hz).

Measurement examples of all instruments will be presented and an outlook to future developments will be discussed.

How to cite: Behrendt, A., Lange, D., Späth, F., Muppa, S. K., Metzendorf, S., Senff, C., and Wulfmeyer, V.: Lidar measurements characterizing the thermodynamic and dynamic structure of the boundary layer up to the turbulence scale, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7191, https://doi.org/10.5194/egusphere-egu2020-7191, 2020.

EGU2020-13708 | Displays | GI4.2

Intercomparison of PBL height estimations in the framework of HyMeX-SOP1

Donato Summa, Paolo Di Girolamo, Benedetto De Rosa, and Fabio Madonna

This paper reports results from an inter-comparison effort involving different sensors/techniques used to measure the Planetary Boundary Layer (PBL) height. The effort took place in the framework of the first Special Observing Period of the Hydrological cycle in the Mediterranean Experiment. The PBL is directly influenced by the Earth's surface, responding to combined action of mechanical and thermal forcing factors. The evolution of the PBL structure and height has important meteorological role. Accurate measurements of the PBL height are important to validate forecast models or support their development through the improvement of the physical representations embedded in, for example, their boundary layer turbulence and shallow convection parameterizations. Elastic backscatter signals and rotational Raman signals collected by lidar systems can be used to characterize the PBL height and its internal structure.  In the present research effort, this technique is compared with measurements from a co-located wind profiler and  a  potential temperature computed from radio-sounding system. Comparisons involving the different sensors will be discussed at the conference.

How to cite: Summa, D., Di Girolamo, P., De Rosa, B., and Madonna, F.: Intercomparison of PBL height estimations in the framework of HyMeX-SOP1, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13708, https://doi.org/10.5194/egusphere-egu2020-13708, 2020.

As part of the Cevennes-Vivarais site, the University of Basilicata Raman lidar system BASIL was deployed in Candillargues and operated throughout the duration of HyMeX-SOP 1 (September-November 2012), providing high-resolution and accurate measurements, both in daytime and night-time, of atmospheric temperature, water vapour mixing ratio and particle backscattering and extinction coefficient at three wavelengths.

Measurements carried out by BASIL on 28 September 2012 reveal a water vapour field characterized by a quite complex vertical structure. Reported measurements were run in the time interval between two consecutive heavy precipitation events, from 15:30 UTC on 28 September to 03:30 UTC on 29 September 2012. Throughout most of this observation period, lidar measurements reveal the presence of four distinct humidity layers.

The present research effort aims at assessing the origin and transport path of the different humidity filaments observed by BASIL on this day. The analysis approach relies on the comparison between Raman lidar measurements and MESO-NH and NOAA-HYSPLIT model simulations. Back-trajectory analyses from MESO-NH reveal that air masses ending in Candillargues at different altitudes levels are coming and are originated from different geographical regions.

The four distinct humidity layers observed by BASIL are also identified in the water vapour mixing ratio profiles collected by the air-borne DIAL LEANDRE 2 on-board of the French research aircraft ATR42. The exact correspondence, in terms of back-trajectories computation and water budget, between the humidity layers observed by BASIL and those identified in LEANDRE2 measurements has been verified based on a dedicated simulation effort.

In the paper we also try to identify the presence of dry layers and cold pools and assess their role in the genesis of the mesoscale convective systems and the heavy precipitation events observed on 29 September 2012 based on the combined use of water vapour mixing ratio and temperature profile measurements from BASIL and water vapour mixing ratio profile measurements from LEANDRE 2, again supported by MESO-NH simulations.

How to cite: Di Girolamo, P., Bouin, M.-N., Flamant, C., Summa, D., and De Rosa, B.: Combined use of Raman lidar and DIAL measurements and MESO-NH model simulations for the characterization of complex water vapour field structures and their genesis: a case study from HyMeX-SOP 1, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16666, https://doi.org/10.5194/egusphere-egu2020-16666, 2020.

EGU2020-16517 | Displays | GI4.2

Laser concept of the mobile ATMONSYS-lidar and its application during CHEESEHEAD

Hannes Vogelmann, Johannes Speidel, and Matthias Perfahl

Water vapor is the most important greenhouse gas and dominates weather patterns, the atmospheric energy budget and radiative balance. For analysing
dynamic processes of planetary boundary layer we developed the ATMONSYS lidar for measuring water vapor, aerosols and temperature. In summer 2019 the application of the ATMONSYS lidar was part of the CHEESEHEAD campaign in Northern Wisconsin (USA). Former investigations showed the very high spatio-temporal short term variability of tropospheric water vapor in a three dimensional study [1]. From a technical point of view this also depicted the general requirement of short integration times while recording water-vapor profiles with lidar. For this purpose,  the differential absorption lidar (DIAL) working in the near-infrared (NIR) spectral region is a suitable technique. For measuring the light absorption by single spectral lines in the 817nm band of water vapor, the laser emission is predominated for the use of Ti:Sapphire as laser medium. We present a new concept of transversely pumping a Ti:Sapphire crystal to generate high power NIR laser emission directly from a laser resonator without amplification stage. This setup allows for a high output power at repetitions rates up to 100Hz or even more due to the enhanced cooling situation for the laser rod. It is, because of its compactness, also suitable for mobile applications. We also show a concept, how this resonator can be locked to two seeding DIAL wavelengths at the same time.

[1] Vogelmann, H., Sussmann, R., Trickl, T., and Reichert, A.: Spatiotemporal variability of water vapor investigated using lidar and FTIR vertical soundings above the Zugspitze, Atmos. Chem. Phys., 15, 3135-3148, 2015.

How to cite: Vogelmann, H., Speidel, J., and Perfahl, M.: Laser concept of the mobile ATMONSYS-lidar and its application during CHEESEHEAD, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16517, https://doi.org/10.5194/egusphere-egu2020-16517, 2020.

EGU2020-20839 | Displays | GI4.2

The ERATOSTHENES Remote Sensing Supersite: Understanding the atmospheric system in the EMMENA region

Argyro Nisantzi, Rodanthi-Elisavet Mamouri, Silas Michaelides, Albert Ansmann, Johannes Bühl, Patric Seifert, Ronny Engelman, Ulla Wandinger, and Diofantos G. Hadjimitsis

The Mediterranean Basin is well recognized by IPCC as a hot spot for climate change. Severe consequences are expected for the future in the Eastern Mediterranean, the Middle East and North Africa (EMMENA) region.

The increased urbanization, high pollution, dust storms and decreasing precipitation in the region dramatically affect climate change. Current prediction models for weather, climate, and environment are based on sophisticated modeling in close connection with state-of-the-art observations.

A modern observational super-site in Cyprus is of fundamental importance to understanding the atmospheric system in the EMMENA region. The presence of such a super site will be able to effectively monitor atmospheric conditions and provide relevant data for atmospheric prediction modeling.

This contribution reports on the recent progress regarding the buildup of a permanent, state-of-the-art atmospheric remote sensing station in Limassol, Cyprus. Through the EU H2020 Teaming project EXCELSIOR, the ERATOSTHENES Centre of Excellence (ECoE) will be established as a Centre of Excellence for Earth Surveillance and Space-Based Monitoring of the Environment.

The ECoE modern in-situ observational super site will be established in Cyprus for long-term profiling of the atmosphere, including wind, humidity, aerosol and cloud properties and precipitation fields. The ECoE will be fully in line with ESFRI networks, such as ACTRIS, as it will utilize state-of-the-art infrastructure and techniques to provide cutting-edge data regarding atmospheric processes.

As a demonstration initiative, an 18-month field campaign (Cy-CARE (Cyprus Cloud Aerosol and pRecipitation Experiment)) has been designed by the Leibniz Institute for Tropospheric Research (TROPOS) and was implemented by the ERATOSTHENES group at Cyprus University of Technology (CUT) between October 2016 and March 2018, with the main focus on lidar/radar-based studies of aerosol-cloud-precipitation relationships. Case studies of the Cy-CARE campaign will be presented to demonstrate the importance of the ground based atmospheric remote sensing observations in the region.

Acknowledgements

The authors acknowledge the EXCELSIOR project that received funding from the European Union [H2020-WIDESPREAD-04-2017:Teaming Phase2] project under grant agreement no. 857510, and from the Republic of Cyprus. CUT team acknowledge ACTRIS-2 project (H2020-INFRAIA-2014-2015, GA no. 654109) and the Research and Innovation Foundation of Cyprus for the financial support through the SIROCCO (EXCELLENCE/1216/0217) and AQ-SERVE (INTERGRATED/0916/0016) projects.

How to cite: Nisantzi, A., Mamouri, R.-E., Michaelides, S., Ansmann, A., Bühl, J., Seifert, P., Engelman, R., Wandinger, U., and G. Hadjimitsis, D.: The ERATOSTHENES Remote Sensing Supersite: Understanding the atmospheric system in the EMMENA region, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20839, https://doi.org/10.5194/egusphere-egu2020-20839, 2020.

EGU2020-21842 | Displays | GI4.2

Numerical Simulation of Ultra-short Laser Pulses Propagation in Gas Media

Katsiaryna Cidorkina, Alexander Svetashev, Ilya Bruchkouski, Siarhei Barodka, and Leonid Turishev

Over the past ten years, important theoretical and practical results have been obtained in the field of interaction of high-power ultra-short laser pulses with solid transparent media. These results are significant for nonlinear optics and laser physics and are of practical interest for the development of femtosecond laser technology in sensing the environment, in the management of electrical discharge, in microphotonics.

However, many of the physical aspects of the supercontinuum generation and distribution of high-power femtosecond and attosecond laser pulses in an optically transparent gas media are not clear and require a detailed theoretical study.

Main objectives of the present study are the numerical simulation of high-intensity femtosecond pulses in the air, given the stimulated Raman scattering (SRS) and the stimulated Raman self-mode (SRSM) on pure nitrogen and oxygen molecules as well as on their mixtures.

Computer programs have been developed for solving nonlinear equations associated with the SRS and SRSM on the basis of a semi-classical energetic and wave theory with the help of numerical methods.

All calculations were made in the Visual Studio C ++ and Java programming environment.

The SRS mode for the distance of up to 5m for the main components of the air - nitrogen (78%) and oxygen (21%), in addition to the dynamics of the change of the pulse energy for different initial values have been calculated.

The propagation of SRMS laser pulses (λ=400, 800 nm; τ= 14, 20 fs) with positive chirp was numerically investigated for pulse energies 2π, π, π/100 and βz = 0.5, 1.0, 1.5.

The results obtained show that the dynamics of pulse propagation in SRMS mode is nonlinear in the pulse shape and spectrum.

It was estimated that the calculation results in energetic and wave models for βz≤1.5 are similar.

How to cite: Cidorkina, K., Svetashev, A., Bruchkouski, I., Barodka, S., and Turishev, L.: Numerical Simulation of Ultra-short Laser Pulses Propagation in Gas Media, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21842, https://doi.org/10.5194/egusphere-egu2020-21842, 2020.

GI4.4 – Sensors networks, instrumentation and measurements for water and climate

EGU2020-5294 | Displays | GI4.4 | Highlight

Monitoring of the mass and heat transfers through a heterogeneous karstic limestone vadose zone of an agricultural field (Beauce Aquifer, Orleans, France)

Bouamama Abbar, Clara Jodry, Arnaud Isch, Gautier Laurent, and Mohamed Azaroual

The extent and the fluid dynamics of the vadose zone (VZ) of an aquifer have a direct impact on the aquifer recharge, the water quality and the pollutants transfer from the soil to the groundwater. The water – rock interactions and mass and heat transfers under the impact of microbial processes and agricultural practices could undergoes significant changes in the chemical composition of the water flowing throughout the VZ, which may induce pollution of groundwater.

The growing dependence on groundwater for potable water supplies draws attention to protect the quality of groundwater resources at national and international levels to the need. It is important to detect the contamination risk of aquifers and develop an integrated water management methodology based on innovative environmental monitoring tools and sophisticated numerical models to protect groundwater resources and guarantee their good quality for domestic, agricultural and industrial needs. For this reason, the monitoring of VZ dynamics has become essential to study the transfer mechanisms of mass (water, gas and contaminants) and heat from the soil to the groundwater. This should allow rapid detection of the pollutants migration through an aquifer and take relevant measures to protect groundwater before the contaminants reach the water table.

In this context, an Observatory of transfers in the vadose zone (O-ZNS) is being developed at Villamblain (Orléans, France) in an agricultural field. The O-ZNS project consists of a well with a diameter of 4 m and a depth of 20 m which will allow access to the entire VZ of the Beauce aquifer. The main target of the O-ZNS platform is to acquire original and unique data on the reactive transfers of fluids and heat in the VZ, in order to follow in situ and in real time the highly coupled physical, chemical, and biological processes taking place over the long term. The O-ZNS project also aims to assess the performance of all types of instrumentation dedicated to non-destructive measurement or local sampling of fluids, rocks, and microbs in the VZ for long duration.

To meet these objectives, a myriad of innovative monitoring tools (e.g.,environmental sensors, fiber optic sensors, geophysical imaging, ….) will be deployed in the O-ZNS from the soil surface to the aquifer (from 0 to 20 m deep) using the well and the surrounding boreholes. Also, note that to date, there are still difficulties in the instrumentation of rock materials and relevant solutions must be developed. These environmental monitoring techniques will allow to generate a huge quantity of data on the physical, chemical, and microbiological coupled processes.

How to cite: Abbar, B., Jodry, C., Isch, A., Laurent, G., and Azaroual, M.: Monitoring of the mass and heat transfers through a heterogeneous karstic limestone vadose zone of an agricultural field (Beauce Aquifer, Orleans, France), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5294, https://doi.org/10.5194/egusphere-egu2020-5294, 2020.

EGU2020-6196 | Displays | GI4.4

USDA UV-B Monitoring and Research Program

Wei Gao, George Janson, Chelsea Corr, and Maosi Chen

Solar Ultraviolet (UV) radiation has significant impacts on human health (e.g., skin cancer) and the environment (e.g., agricultural production and plant litter decomposition). Reductions in UV-absorbing stratospheric ozone resulting from climate change and the anthropogenic emission of ozone depleting substances raised concerns regarding future levels of surface UV radiation. Responding to this potential threat, the U.S. Department of Agriculture (USDA) investigated the need for UV monitoring across the U.S. in 1991 and established the UV-B Monitoring and Research Program (UVMRP) headquartered in Natural Resource Ecology Laboratory at Colorado State University later in 1992. The UVMRP is tasked with providing information on the geographical distribution and temporal trends of UV radiation and studying the effects of UV radiation on a wealth of agricultural interests including crop plants, rangelands, and forests. The UVMRP currently consists of 37 climatological monitoring sites and 4 research sites, most of which are distributed across the U.S., with an additional site in Canada and another in New Zealand. Collectively, these sites encompass 20 ecoregions. Each UVMRP site is equipped with four primary irradiance instruments including the: 1) UV MultiFilter Rotating Shadowband Radiometer (UV-MFRSR), 2) visible MFRSR, 3) UVB-1 broadband meter, and 4) Photosynthetically Active Radiation (PAR) sensor. The UV-MFRSR measures total horizontal, diffuse horizontal, and direct normal irradiance at nominal 300, 305, 311, 317, 325, 332, and 368 nm at 2 nm FWHM (full-width half-maximum). The VIS-MFRSR measures the same three irradiance components at nominal SiC, 415, 500, 610, 665, 860, and 940 nm at 10 nm FWHM. PAR and UVB-1 sensors measure broadband irradiances over the 400-700 nm and 280-320 nm ranges, respectively. All these observations are sampled every 15 or 20 seconds and stored as an average value every three minutes. The raw data measurements are processed following a variety of Quality Control (QC) and calibration procedures to ensure the quality of the data. The primary data products (i.e., irradiances) as well as the derived products (e.g., UV Index and weighted daily/hourly sums) are distributed through the UVMRP website (http://uvb.nrel.colostate.edu). In this poster, we present a UV climatology study that explores long-term trends of erythemal irradiance at eight locations across the U.S. derived from 8-11 years of UVMRP measurements.

How to cite: Gao, W., Janson, G., Corr, C., and Chen, M.: USDA UV-B Monitoring and Research Program, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6196, https://doi.org/10.5194/egusphere-egu2020-6196, 2020.

Streamflow is of fundamental importance to hydrology and water resources management, but it is difficult and/or expensive to measure directly in a continuous manner. Consequently, continuous measurements mostly make use of stage recording, with the values of stage being converted into those of streamflow by means of rating curves (or a digital counterpart). Historically, a major practical advantage of a one input – one output stage-discharge relationship was its straightforward handling in the form of a diagram, but that is no longer relevant. Thus, there is little reason why streamflows should be inferred from stage only, provided an additional input variable proves useful and can easily (and inexpensively) be recorded continuously.

Electrical conductivity (EC) appears as a potentially powerful candidate to serve as a further input variable improving streamflow estimates, and artificial neural networks (ANNs) are well suited to handle more than one input. In alpine streams EC has been reported to be a viable alternative to water level as predictor variable in streamflow estimation (Weijs et al., 2013). The approach advocated here differs from that just cited by using EC in addition to, not in lieu of stage as predictor variable. That way, it is believed that the field of potential application should be wider. In the work reported here, stage and EC data were used to develop a multilayer perceptron type ANN (2-4-1) to estimate flow in a small Austrian stream (Mödling) with a catchment of fairly mixed composition (forested, agricultural and urbanized areas). While the alpine catchment studied by Weijs et al.(op. cit.) probably is at the upper end of EC usefulness in streamflow estimation, the Mödling catchment offers less favourable conditions, with EC being potentially subject to some influence of human activities. In spite of these modest (but not unusual) conditions, the research reported documents that EC improved streamflow estimates. An analysis of the data with the aid of a network interpretation diagram, Garson's algorithm (Garson, 1991) and a sensitivity analysis performed on the two input variables (stage and EC, resp.) shows EC to be a useful additional predictor, with its relative 'importance' amounting to roughly one third of that of stage in this catchment.

References

Garson, G.D.: Interpreting neural-network connection weights. Artif. Intell. Expert, 6, 47-51, 1991.

Weijs, S.V., Mutzner, R., Parlange, M.B.: Could electrical conductivity replace water level in rating curves for alpine streams? Water Resour. Res 49, 343-351, 2013.

How to cite: Schmid, B. H.: Enhanced flow rating using neural networks with water stage and electrical conductivity as predictors, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1804, https://doi.org/10.5194/egusphere-egu2020-1804, 2020.

EGU2020-2223 | Displays | GI4.4

In-Situ Validation of Water Quality Algorithms and Monitoring of Irish Lakes using Sentinel 2 Imagery

Sita Karki, Kevin French, Valerie McCarthy, Jennifer Hanafin, Eleanor Jennings, Conor Delaney, Vicky Veerkamp, Aaron Golden, Alastair McKinstry, and Moataz Ahmed

Through Remote Sensing of Irish Surface Water (INFER) project, we are validating the algorithms to measure the  water quality using Sentinel 2 imagery, which comprises of two European Space Agency (ESA) terrestrial satellites with combined temporal resolution of 5 days. The project is focused on selection of optimal algorithms that will be applicable in Irish context in relation to the high cloud cover and relatively small sizes of the water bodies. The current procedure entails collection of reflectance data from the lakes during the Sentinel overpass as it helps to identify the correct atmospheric correction algorithm. Field radiometry tasks were carried out using TRIOS RAMSES radiometers. Standard field procedures were employed for acquiring glint free reflectance from the water bodies.

Historical data collected from the 11 lakes, which had field bathymetry survey data, were analysed in order to determine the influence of environmental conditions on the quality of samples. Based on the analysis, recommendations to collect field samples from areas deeper than 10 m and 30 m away from the shoreline were provided in order to avoid the reflectance from the bottom and the surrounding topography. A site selection process was undertaken during the spring of 2019 to shortlist appropriate sites for field validation of satellite-derived products. A total of fifteen lakes were identified for field validation based on several criteria so as to ensure lakes with varying size, depth, trophic status and Water Framework Directive (WFD) status . In addition, a timetable for proposed sampling was established by drawing up a timetable of satellite passes starting from summer of 2019. C2RCC and Acolite processors are being used to compute the chlorophyll and turbidity from identified lakes. Considering the fast changing weather condition of Ireland, it was difficult to obtain the exact overlap between the sentinel overpass and the field sampling. In order to address this issue, the field samples collected within 10 days from the sensor overpass were considered for the field validation. Study of the satellite derived water chemistry data showed that the data collected outside of that time window may not represent the natural fluctuation that occurs in the water bodies.

The end product of this project is the web platform with the access to Sentinel 2 MSI data products where users can visualize the water quality products for Ireland. This platform will promote the use of earth observation data for inland water quality monitoring and would enable sustainable utilization of the water resources.

How to cite: Karki, S., French, K., McCarthy, V., Hanafin, J., Jennings, E., Delaney, C., Veerkamp, V., Golden, A., McKinstry, A., and Ahmed, M.: In-Situ Validation of Water Quality Algorithms and Monitoring of Irish Lakes using Sentinel 2 Imagery , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2223, https://doi.org/10.5194/egusphere-egu2020-2223, 2020.

EGU2020-7133 | Displays | GI4.4 | Highlight

SentiLake - Sentinel-2 satellite data-based service for monitoring of Latvian lakes

Dainis Jakovels, Agris Brauns, Jevgenijs Filipovs, and Tuuli Soomets

Lakes and water reservoirs are important ecosystems providing such services as drinking water, recreation, support for biodiversity as well as regulation of carbon cycling and climate. There are about 117 million lakes worldwide and a high need for regular monitoring of their water quality. European Union Water Framework Directive (WFD) stipulates that member states shall establish a programme for monitoring the ecological status of all water bodies larger than 50 ha, in order to ensure future quality and quantity of inland waters. But only a fraction of lakes is included in in-situ monitoring networks due to limited resources. In Latvia, there are 2256 lakes larger than 1 ha covering 1.5% of Latvian territory, and approximately 300 lakes are larger than 50 ha, but only 180 are included in Inland water monitoring program, in addition, most of them are monitored once in three to six years. Besides, local municipalities are responsible for the management of lakes, and they are also interested in the assessment of ecological status and regular monitoring of these valuable assets. 

Satellite data is a feasible way to monitor lakes over a large region with reasonable frequency and support the WFD status assessment process. There are several satellite-based sensors (eg. MERIS, MODIS, OLCI) available specially designed for monitoring of water quality parameters, however, they are limited only to use for large water bodies due to a coarse spatial resolution (250...1000 m/pix). Sentinel-2 MSI is a space-borne instrument providing 10...20 m/pix multispectral data on a regular basis (every 5 days at the equator and 2..3 days in Latvia), thus making it attractive for monitoring of inland water bodies, especially the small ones (<1 km2). 

Development of Sentinel-2 satellite data-based service (SentiLake) for monitoring of Latvian lakes is being implemented within the ESA PECS for Latvia program. The pilot territory covers two regions in Latvia and includes more than 100 lakes larger than 50 ha. Automated workflow for selecting and processing of available Sentinel-2 data scenes for extracting of water quality parameters (chlorophyll-a and TSM concentrations) for each target water body has been developed. Latvia is a northern country with a frequently cloudy sky, therefore, optical remote sensing is challenging in or region. However, our results show that 1...4 low cloud cover Sentinel-2 data acquisitions per month could be expected due to high revisit frequency of Sentinel-2 satellites. Combination of C2X and C2RCC processors was chosen for the assessment of chl-a concentration showing the satisfactory performance - R2 = 0,82 and RMSE = 21,2 µg/l. Chl-a assessment result is further converted and presented as a lake quality class. It is expected that SentiLake will provide supplementary data to limited in situ data for filling gaps and retrospective studies, as well as a visual tool for communication with the target audience.

How to cite: Jakovels, D., Brauns, A., Filipovs, J., and Soomets, T.: SentiLake - Sentinel-2 satellite data-based service for monitoring of Latvian lakes, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7133, https://doi.org/10.5194/egusphere-egu2020-7133, 2020.

EGU2020-7813 | Displays | GI4.4

Introduction to the second Geostationary Ocean Color Imager (GOCI-II) and its ground segment

Hee-Jeong Han, Jae-Moo Heo, Hyun Yang, Woo-Chang Choi, Hey-Min Choi, and Young-Je Park

As the succeeder of the Geostationay Ocean Color Imager (GOCI), the world first geostationary ocean monitoring satellite, the second GOCI (GOCI-II) will be launched in 2020. GOCI-II has 12 narrow bands of 380~865nm center wavelength for earth observation and an broadband band for star observation. The main goals of this GOCI series are to monitor ocena short-term/long-term phenomena like red-tide blooming, floating algae movements, tidal movements, low sea surface salinity variation, sea surface currents, primary productivity, etc. GOCI-II is able to obtain 10 images for the area around Korean peninsula and an image for the full-disk area in everyday during its 10 years lifetime. To handle this huge GOCI-II data, we have to develop the dedicated GOCI-II Ground Segment (G2GS) system with data acquisition antenna and GOCI-II operating infrastructure. G2GS have good performance like the data distribution output delay within 60 minutes, the 99% system operability with redundancy, etc. G2GS also generates 26 level-2 data products and provides all data with dedicated software program like GOCI-II plug-in of SNAP framework. 

How to cite: Han, H.-J., Heo, J.-M., Yang, H., Choi, W.-C., Choi, H.-M., and Park, Y.-J.: Introduction to the second Geostationary Ocean Color Imager (GOCI-II) and its ground segment, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7813, https://doi.org/10.5194/egusphere-egu2020-7813, 2020.

EGU2020-10409 | Displays | GI4.4

Water vapor measurements in central México using two remote sensing techniques: FTIR spectroscopy and GPS

Alain Zuber, Wolfgang Stremme, Michel Grutter, David Adams, Thomas Blumenstock, Frank Hase, and Matthias Schneider

Atmospheric water vapor plays a key role in weather and climate. Knowledge about its variability, diurnal and seasonal cycles, as well as its long-term trend is necessary to improve our understanding of the hydrological cycle. H2O total columns are measured by the two remote sensing techniques, ground-based solar absorption FTIR spectroscopy and a GPS (Global Positioning System) receiver, over a site in central Mexico. The Altzomoni Atmospheric Observatory (3989 m a.s.l., 19.32ºN, 98.65ºW) is a high altitude station located within the Izta-Popo national park, 60 km SE from Mexico City. The time series of GPS and FTIR show a high correlation between coincident hourly means. Both techniques are complementary since despite that GPS works throughout day and night and also in cloudy and rainy weather conditions, the FTIR data provides in addition altitude-resolved information about the atmospheric water vapor and permits to distinguish different isotopes.

In this study, we show water vapor columns in the 2013 to 2019 period for this region retrieved from FTIR and GPS measurements and preliminary results about their isotopic composition (H216O, H218O and HD16O). We discuss the opportunity to study the hydrological cycle in central Mexico using the relationship between light and heavy isotopes, a relationship that gives valuable information about the sources and transport pathways.

How to cite: Zuber, A., Stremme, W., Grutter, M., Adams, D., Blumenstock, T., Hase, F., and Schneider, M.: Water vapor measurements in central México using two remote sensing techniques: FTIR spectroscopy and GPS, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10409, https://doi.org/10.5194/egusphere-egu2020-10409, 2020.

EGU2020-10452 | Displays | GI4.4 | Highlight

Internet of Things Technologies for the Efficient Collection of Hydrological Measurement Data

Sebastian Drost, Jan Speckamp, Carsten Hollmann, Christian Malewski, Matthes Rieke, and Simon Jirka

The collection of hydrological measurement data comprises a broad range of challenges beyond the development and deployment of sensing devices. Especially the transmission of the collected (raw) data to central data servers may be a challenging task depending on the available infrastructure.

In our presentation we will discuss the applicability of Internet of Things (IoT) technologies to enable a lightweight data collection workflow relying on the Message Queuing Telemetry Transport (MQTT) protocol as well as the SensorThings API standard of the Open Geospatial Consortium (OGC). These standards are especially optimised to reduce communication overheads, to be viable via resource constrained communication links, and to support a seamless plug-and-play integration of new measurement devices.

As part of this presentation, we will introduce the communication patterns and messages used by the data collection mechanism. This will be combined with a discussion how these IoT standards can be coupled to existing sensor hardware and which types of communication link can be used. Afterwards, we will also discuss the design of a data management server that integrates the collected measurement data. This comprises on the one hand connectors to the IoT data streams but on the other hand also data management and storage functionality, as well as interoperable interfaces for sharing the collected data.

For the validation of the presented concept, a pre-operational deployment at the Wupperverband, a regional water management association in Germany, will be shown. This comprises not only the practical experiences gained during the operation but also recommendations on future challenges such as semantic interoperability (e.g. vocabularies) as well as the efficient management of large amounts of incoming time series data (e.g. via dedicated database concepts).

Thus, in summary our contribution aims to contribute to the discussion on how IoT technologies may help to facilitate the collection of hydrological measurement data and to support the sharing of such data.

How to cite: Drost, S., Speckamp, J., Hollmann, C., Malewski, C., Rieke, M., and Jirka, S.: Internet of Things Technologies for the Efficient Collection of Hydrological Measurement Data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10452, https://doi.org/10.5194/egusphere-egu2020-10452, 2020.

EGU2020-10660 | Displays | GI4.4 | Highlight

Connecting data streams with On-Demand Services in the Alpine Environmental Data Analysis Centre

Johannes Munke, Alexander Götz, Helmut Heller, Stephan Hachinger, Dominik Laux, Oleg Goussev, Jana Handschuh, Sabine Wüst, Michael Bittner, Roland Mair, Bianca Wittmann, Till Rehm, Inga Beck, and Markus Neumann

The AlpEnDAC (Alpine Environmental Data Analysis Center) platform (www.alpendac.eu) aims to collect scientific data measured on different high-altitude research stations in the alpine region and beyond. It provides research data management, analysis and simulation services and supports the research activities of the VAO (Virtual Alpine Observatory) community.

With funding from the Bavarian State Ministry of the Environment and Consumer Protection, a new development cycle of the platform was launched in 2019. Novel components for Computing on Demand (CoD), Service on Demand (SoD) and Operating on Demand (OoD) will be integrated into the system. These will help to implement a near-real-time (NRT) decision support for the scientist during measurement processes and a better control of the measurement process.

In this work, the authors present a stream processing architecture to couple the new CoD, SoD and OoD components. Data from measurements (or also simulations) are normally ingested via a representational state transfer application programming interface (REST API) into the AlpEnDAC system. Before such data are stored in the data base, they will be run through a central stream processing engine, based on a message queue (e.g. Apache Kafka) and a series of specialized workers to process the data. A rule engine and analytics tools are connected to this engine and allow the automatic triggering of, e.g., measurements, HPC simulations, or evaluation and notification services in NRT. The services will be usable and configurable, as much as possible, via the AlpEnDAC web portal where also certain measurement device settings can be adjusted. With these developments, we want to make environmental scientists profit from NRT data collection and processing, as it is already an everyday tool, e.g., in the Internet-of-Things sector and in commercial applications.

How to cite: Munke, J., Götz, A., Heller, H., Hachinger, S., Laux, D., Goussev, O., Handschuh, J., Wüst, S., Bittner, M., Mair, R., Wittmann, B., Rehm, T., Beck, I., and Neumann, M.: Connecting data streams with On-Demand Services in the Alpine Environmental Data Analysis Centre, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10660, https://doi.org/10.5194/egusphere-egu2020-10660, 2020.

EGU2020-12320 | Displays | GI4.4 | Highlight

Introducing Sage: Cyberinfrastructure for Sensing at the Edge.

Scott Collis, Pete Beckman, Eugene Kelly, Charles Catlett, Rajesh Sankaran, Ikay Altintas, Jim Olds, Nicola Ferrier, Seongha Park, Yongho Kim, and Michael Papka

There are many networks of sensors for earth system science. Most networks are local or regional in scale (eg mesonets). National weather services maintain networks for meeting stakeholder needs and responsibilities to the WMO Global Observing System. These systems are comprised of single task rigid sensors generally attached to logger systems. Sage [1] is a project which will deliver a cyberinfrastructure network allowing multi-tenant, multi-tasked sensor packages. In addition to traditional meteorological instrumentation and advanced static and pan-tilt-zoom cameras Sage nodes have powerful compute infrastructure allowing machine learning based phenomenology detection at the edge. This allows science question-based reconfiguration of sensor operation. A well described Application Programming Interface (API) will allow new algorithms to be pushed to the edge and new sensor packages to be added including those that have complex configuration spaces like LIDAR and Radar. This presentation will introduce Sage and present early example results such as using cameras for cloud classification, inundation caused by heavy rainfall and early wildfire ignition detection. 

 

[1]  https://www.research.northwestern.edu/world-watchers/

How to cite: Collis, S., Beckman, P., Kelly, E., Catlett, C., Sankaran, R., Altintas, I., Olds, J., Ferrier, N., Park, S., Kim, Y., and Papka, M.: Introducing Sage: Cyberinfrastructure for Sensing at the Edge., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12320, https://doi.org/10.5194/egusphere-egu2020-12320, 2020.

EGU2020-15913 | Displays | GI4.4

PIONEER: open wireless sensor network for smart environmental monitoring of remote areas

Federico Dallo, Daniele Zannoni, Fabrizio de Blasi, Jacopo Gabrieli, Carlo Barbante, Paolo Bonasoni, Paolo Cristofanelli, Francescopiero Calzolari, Ann Mari Fjaeraa, Are Bäcklund, and Fred Bauman

Atmospheric observatories in the remote areas represent the primary infrastructure for the state-of-the-art meteorological and climate research and play a crucial role in Climate Change comprehension. However, the World Meteorological Organization Global Atmosphere Watch (WMO-GAW) states in their 2018 final report that “the fate of the next generation of monitoring stations will be dramatically modified by the breakthroughs of new low-cost sensor (LCS) technologies.”. The development and improvement of low-cost technologies are proving notable applications and today LCSs are already playing a crucial role in fields such as model or emission validation and spatial variability of pollution[1]. Upcoming earth observation programmes, applications, services and support in citizen inclusion in earth monitoring are pushing the European Union (EU) in funding R&D to assess low-cost technologies, thus making the introduction of basic and applied research imperative.
PIONEER* aims at establishing a low-cost wireless sensor network (LCS-WSN) for the study of transboundary transport phenomena of air pollutants. Given its highly relevance for the Earth climate, ecosystems, and human health, primary endeavor will be directed towards the study of tropospheric ozone to obtain quantitative, reproducible in-situ measurements. Tropospheric ozone is one of the most important atmospheric gases involved in photochemical reactions[2], it plays a central role in the radiative budget of the atmosphere and it is the third greenhouse gas in the troposphere[3]. Also, surface ozone is a dangerous secondary pollutant causing harm to human health and ecosystems[4]. Since the troposphere is a very complex system the goal is to develop and deploy a reliable LCS-WSN, along the trail Munich-Venice, to be used by scientists as well as citizen engineers in remote areas, where the needs of reliable dense spatial data to model the transport phenomena and Climate Change effects is decisive. 
PIONEER will exploit the existing open source technologies and commercial low-cost sensors to provide a LCS-WSN systems for long term climate data collection, a cloud-assisted database for time series collection and management, a web portal for uploading, displaying, performing statistical analysis and downloading records and metadata in a fully open access fashion, a comprehensive open source repository with tools, guidelines and application developed. The software will be open-source and released under copyleft license, thus allowing the complete reproducibility of all the developed devices and tools. 

*Individual Global Fellowships granted by the Research Executive Agency. 
Grant Agreement number: 844526 — PIONEER — H2020-MSCA-IF-2018

[1] Lewis, Alastair, W. Richard Peltier, and Erika von Schneidemesser. "Low-cost sensors for the measurement of atmospheric composition: overview of topic and future applications." (2018).

[2] Crutzen, P.J., Lawrence, M.G., Poschl, U.,“On the background photochemistry of tropospheric ozone”, Tellus AB 51, 123–146 (1999).

[3] Forster, Piers, et al. "Changes in atmospheric constituents and in radiative forcing. Chapter 2." Climate Change 2007. The Physical Science Basis. 2007.

[4] Cooper, Owen R., et al. "Global distribution and trends of tropospheric ozone: An observation-based review." (2014).

[5] Young, P. J., et al. "Pre-industrial to end 21st century projections of tropospheric ozone from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)." Atmospheric Chemistry and Physics 13.4 (2013): 2063-2090.

How to cite: Dallo, F., Zannoni, D., de Blasi, F., Gabrieli, J., Barbante, C., Bonasoni, P., Cristofanelli, P., Calzolari, F., Fjaeraa, A. M., Bäcklund, A., and Bauman, F.: PIONEER: open wireless sensor network for smart environmental monitoring of remote areas, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-15913, https://doi.org/10.5194/egusphere-egu2020-15913, 2020.

Over the past decade, the global proliferation of cyanobacterial harmful algal blooms (CyanoHABs) have presented a major risk to the public and wildlife, and ecosystem and economic services provided by inland water resources. As a consequence, water resources, environmental, and healthcare agencies are in need of early information about the development of these blooms to mitigate or minimize their impact. Results from various components of a novel multi-cloud cyber-infrastructure for initial detection and continuous monitoring of spatio-temporal growth of CyanoHABs is highlighted in this study. The novelty of this CyanoTRACKER framework is the integration of community reports, remote sensing data and digital image analytics to differentiate between regular algal blooms and CyanoHABs. Individual components of CyanoTRACKER include a reporting website, mobile application (App), remotely deployable solar powered enabled automated hyperspectral sensor (CyanoSense), and a cloud-based satellite data processing and integration tool. All components of CyanoTRACKER provided important data related to CyanoHABs assessments for regional and global waterbodies. Reports and data received via social cloud including the mobile App, Twitter, Facebook, and CyanoTRACKER website, helped in identifying the geographic locations of CyanoHABs infested waterbodies. A significant increase (124.92%) in tweet numbers related to CyanoHABs was observed between 2011 (total relevant tweets = 2925) and 2015 (total relevant tweets = 6579) that reflected an increasing trend of the harmful phenomena across the globe as well as increased awareness about CyanoHABs among Twitter users. The CyanoHABs infested geographic locations extracted via social cloud were utilized for the deployment of CyanoSense at smaller waterbodies and analysis of satellite data for larger waterbodies. CyanoSense was able to differentiate between ordinary algae and CyanoHABs through the use of their characteristic absorption feature at 620nm. The results and products from this infrastructure can be rapidly disseminated via CyanoTRACKER website, social media, and direct communication with appropriate management agencies for issuing warnings and alerting lake managers, stakeholders and ordinary citizens to the imminent dangers posed by these environmentally harmful phenomena.

How to cite: Mishra, D.: CyanoTRACKER: A cloud-based integrated multi-platform architecture for global observation of cyanobacterial harmful algal blooms , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10822, https://doi.org/10.5194/egusphere-egu2020-10822, 2020.

EGU2020-19513 | Displays | GI4.4 | Highlight

Water well logging and automatic log interpretation technology

Yuri Manstein and Kamil Alsynbaev

The presented work is fully practical. Hydrogeological (water) well logging is very different from a petroleum well logging in terms of equipment and budget. A water uplift well cost is quite low, and it is not make a big economic sense to use automatic well logging systems for it. Hence, a lot of engineers are trying to "invent" their own resistivity logging tools or just use a conventional AMNB equipment for surface electrical prospecting to explore the water wells. It is feasible, because a water depth and, consequently, the logging cable length is usually limited by 200 m, it is not hard to pull the cable manually. Such a solution is very cheap and easy to implement. However, the process of logging take time and includes hundreds of steps. So, errors in the process is often.

The aim of this work is to adapt electric resistivity imaging system SibEr for well logging, simplify the logging process and create the possibility for a well drilling team to make the well logging themselves, including the recommendation of the filter installation depth.

The solution includes:

- Hardware: well logging cable with 32 (24) takeouts at the bottom hole end with 20 cm spacing;

- Embedded software for resistivity and induced polarization data acquisition;

- Data processing software to create the logging report with diagrams and suggested filter intervals.

 

How to cite: Manstein, Y. and Alsynbaev, K.: Water well logging and automatic log interpretation technology, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19513, https://doi.org/10.5194/egusphere-egu2020-19513, 2020.

In the past decades, space-based Earth Observations (EO) have been rapidly advancing in monitoring the global water cycle, in particular for the variables related to precipitation, evapotranspiration and soil moisture, often at (tens of) kilometre scales. Whilst these data are highly effective to characterise water cycle variation at regional to global scale, they are less suitable for sustainable management of water resource, which needs more detailed information at local and field scale due to inhomogeneous characteristics of the soil and vegetation. To effectively exploit existing knowledge at different scales we thus need to answer the following questions: How to downscale the global water cycle products to local scale using multiple sources/scales of EO data? How to explore and apply the downscaled information at the management level for understanding soil-water-vegetation-energy processes? And how to use such fine-scale information to improve the management of soil and water resources? An integrative information aqueduct (iAqueduct) is proposed to close the gaps between global satellite observation of water cycle and local needs of information for sustainable management of water resources. iAqueduct aims to accomplish its goals by combining Copernicus satellite data (with intermediate resolutions) with high resolution Unmanned Aerial System (UAS) and in-situ observations to develop scaling functions for soil properties and soil moisture and evapotranspiration at high spatial resolution scales.

How to cite: zeng, Y. and the iAqueduct Team: An Integrative Information Aqueduct to Close the Gaps between Global Satellite Observation of Water Cycle and Local Sustainable Management of Water Resources (iAqueduct), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9782, https://doi.org/10.5194/egusphere-egu2020-9782, 2020.

EGU2020-16541 | Displays | GI4.4

New generation of sensors for landslide observation: first results

Raphaël Chochon, Thomas Lebourg, Nicolas Martin, Maurin Vidal, Mickaël Hernandez, Romain Besso, and Yoann Drouillas

Rupture processes comprehension and dynamics of slope movements have been studied for several decades through surface observations of unstable objects (INSAR, LIDAR, geomorphological...) and very punctually in the slid masses (inclinometric survey). That kind of observations usually requires heavy amenities that are energy-consuming, vulnerable, and very expensive. We have developed within a public-private partnership a new generation of connected sensors. In this paper, we present a set of displacement data collected on active landslides located in the Alpes-Maritimes region of France. This is a region subject to intense climatic forcing, in areas of high vulnerability, and potentially a hotspot of climate change in the coming years. This climate, referred as North Mediterranean, is defined by intense rainfall (>100mm/day). This territory is particularly vulnerable due to its abrupt pre-Alps reliefs, which are located very close to the sea, and also constrained by strong urban pressure.

The acquisition of good-quality observational data and the installation of sensors on this type of landslide remain a difficult scientific challenge which is full of compromises in an attempt to obtain, in the long term, effective warning systems. The accessibility of the study site, its lithologic and hydrogeological complexities, and the management of the installed sensors (energy resource, location representative of the mass, cost ...) are issues to the development of these systems.

Two sites instrumented during 2019 suffered from heavy weather during autumn (cumulative rainfall of more than 800 mm over 2 months), causing an acceleration of the displacements, and allowing us to watch the transition from the latency phase to the gravitational paroxysm. This period of severe weather is part of a succession of climatic events that we call "Mediterranean events", producing cumulative rainfall in a few hours/days/weeks higher than the yearly normals.

The data set presented and discussed consists of (1) meteorological observations (with a focus on rainfall accumulation), (2) piezometric observations (subsurface ground water level and conductivity), (3) borehole inclinometer measurements, (4) GNSS displacement observations (daily solutions), (5) displacement observations between two points using laser rangefinders, and (6) surface clinometric observations.

This new generation of sensors increases the frequency of measurement, which makes it possible to visualize the “life of the slope” and thus to refine the knowledge of the transition phases. These dormant phases, or saturation, are key moments in the transition from a stable state to an unstable state, and reveal the “breathing” of the slope.

This communication will be made in the framework of a PhD funded by the socio-economic partner Azur Géo Logic, and the Provence-Alpes-Côte d'Azur region.

How to cite: Chochon, R., Lebourg, T., Martin, N., Vidal, M., Hernandez, M., Besso, R., and Drouillas, Y.: New generation of sensors for landslide observation: first results, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16541, https://doi.org/10.5194/egusphere-egu2020-16541, 2020.

EGU2020-17909 | Displays | GI4.4

A modified dielectric probe for increased measurement volume of soil water content

Aleksandra Woszczyk, Justyna Szerement, Arkadiusz Lewandowski, Marcin Kafarski, Agnieszka Szypłowska, Andrzej Wilczek, and Wojciech Skierucha

The information of water amount in soil is essential in many fields (e.g. agriculture, forestry, hydrology). Methods to determine water content (WC) can be classified as direct and indirect. Direct methods are connected with the destruction of a sample, are time-consuming and impractical for the measurements in the crop fields. Indirect methods ensure non-destructive and in situ measurements and depend on monitoring a dielectric soil property which is a function of WC. The soil dielectric permittivity is one of the used properties which may be determined by time domain reflectometry (TDR) or frequency domain reflectometry (FDR) techniques. TDR probes are expensive and can be easily damaged at multiple insertions to soil. The open-ended (OE) probes, well-known for their application in the measurements of the complex dielectric permittivity of materials in broadband frequency range, are more resistant to mechanical damage but they are characterized by low penetration depth of electromagnetic waves. Therefore, there is a need to develop sensors able to measure bigger volumes and at the same time sufficiently durable for multiple insertions in soil.     

The objective of this work was to test the performance of an open-ended dielectric probe with an antenna (OE-A) in the frequency range 1 MHz – 6 GHz for two mineral soils using vector network analyzer (VNA) one port (reflective) measurements. Firstly, numerical simulations of the probe using Ansys HFSS software were performed. Secondly, the probe calibration was done on the reference materials (air, distilled water and ethanol). Thirdly, the soils measurements were done to check the possibility to determine soil moisture.   

The obtained results show that the tested probe can be applied for fast moisture measurement with minimal soil disturbance. The real part of dielectric permittivity (ε’) obtained for the tested soils was connected with their moisture and the relation between ε’ and volumetric water content was determined. Additionally, the effect of the sample volume was considered and the relation between the high-frequency limit and diameter of the sample was determined.     

Acknowledgement:

This research was supported by the National Centre for Research and Development (BIOSTRATEG/343547/8/NCBR/2017).

How to cite: Woszczyk, A., Szerement, J., Lewandowski, A., Kafarski, M., Szypłowska, A., Wilczek, A., and Skierucha, W.: A modified dielectric probe for increased measurement volume of soil water content, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17909, https://doi.org/10.5194/egusphere-egu2020-17909, 2020.

EGU2020-20889 | Displays | GI4.4

Detecting Pipeline Leakage in Long-Distance Water Transmission: Case Study in Liaoning Province, China

Fengbin Li, Jianqiang Fan, and Jinn-Chyi Chen

Pipeline leakage inevitably occurs in the long-distance water transmission process. If a leak cannot be identified and processed promptly, it can cause severe economic losses or environmental pollution. This paper proposes a method to evaluate pipeline leakages in long-distance water transmission. The pipeline located in Liaoning Province was selected; it is 63.97-km long and runs from west Shenyang to Liaoyang city. Flowrate time-series data were obtained from two flowrate stations; the data were measured using ultrasonic flowmeters. The variance and mean values of flowrate time-series data were determined and used to evaluate whether pipeline leakage occurs. A Chi-Square test was used to test if the variance of a flowrate time-series was equal to a specified value. The results indicate the following: (1) the method of variance test can be used to evaluate whether the pipeline operation is abnormal or not; (2) when the variance test on time series data of flowrate is abnormal for more than two days, the pipeline leakage situation can be evaluated; (3) the combination of the variance test and the mean value analysis can help locate the leak position, which provides a reference for site personnel. The method proposed in this paper can detect pipeline leakage in a timely manner, and further ensure normal water transmission operation in many cities downstream.

How to cite: Li, F., Fan, J., and Chen, J.-C.: Detecting Pipeline Leakage in Long-Distance Water Transmission: Case Study in Liaoning Province, China, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20889, https://doi.org/10.5194/egusphere-egu2020-20889, 2020.

EGU2020-18903 | Displays | GI4.4

Real time data quality control applied on an IOT sensor water quality network

Matthias Maeyens, Brianna Pagán, Piet Seuntjens, Bino Maiheu, Nele Desmet, Maarten van Loo, and Stijn van Hoey

In recent years, extend periods of drought have been affecting the water quality and availability in  the Flanders region in Belgium. Especially the coastal region experienced an increased salinization of ground and surface water. The Flemish government therefore decided to invest in a dense IoT water quality monitoring network aiming to deploy 2500 water quality sensors  primarily in surface water but also in ground water and sewers. The goal of this "Internet of Water" project is to establish an operational state of the art monitoring and prediction system in support of future water policy in Flanders. 

Since Flanders is a relatively small region (13,522 km²), placing this many sensors will result in one of the most dense surface water quality sensor networks in the world. Each sensor will continuously measure several indicators of water quality and transmit the data wirelessly. This allows us to continuously monitor the water quality and build a big enough data set to be able to use a more data driven approach to predicting changes  in water quality. However, as with any sensor system, the quality of the data can vary in time due to problems with the sensors, incorrect calibration or unforeseen issues. Real-time data quality control is crucial to prevent unsound decisions due to faulty data.

This contribution will give a general overview of the network and it’s specifications, but mainly focus on the implementation of the data stream as well as methods that are implemented to guarantee good data quality. More specifically the architecture and setup of a real-time data quality control system is described. Which will add quality control flags to measurements.  This system is  integrated with the NGSI API introduced by FIWARE, which forces us to make specific design decisions to acommodate to the NGSI API.

How to cite: Maeyens, M., Pagán, B., Seuntjens, P., Maiheu, B., Desmet, N., van Loo, M., and van Hoey, S.: Real time data quality control applied on an IOT sensor water quality network, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18903, https://doi.org/10.5194/egusphere-egu2020-18903, 2020.

EGU2020-18824 | Displays | GI4.4

Low-cost sensor system based on LoraWAN for monitoring water distribution systems

Harald Roclawski, Thomas Krätzig, Benjamin Dewals, Laurent Vercouter, Aloysio Saliba, Anika Theis, Thomas Pirard, Henrique Donancio, Pierre Archambeau, and Sébastien Erpicum

In the research project Iot.H2O, which is funded under the Water JPI Joint Call 2017 IC4WATER, the potential of the Internet of Things concept is investigated for monitoring and controlling water distribution systems. Smart sensors are used which send data via LoraWAN to gateways which are connected to the Internet. The aim of the project is to use low-cost sensors and open-source software.

In the presentation, a prototype on a laboratory scale will be shown. The design of the monitoring system will be explained in detail and compared to the design of standard SCADA systems. Results on a pump test rig based on a laboratory scale will be shown as well as first results of field tests in a real water distribution system in Germany.

The presentation will also detail how data gathered through the smart sensors will be integrated into software modelling and optimization of water distribution systems. Combined with the new data, such tools offer a range of applications of practical relevance, such as the identification of optimal locations of micro-turbines for energy recovery in water distribution networks and the estimation of water demand throughout the network.

How to cite: Roclawski, H., Krätzig, T., Dewals, B., Vercouter, L., Saliba, A., Theis, A., Pirard, T., Donancio, H., Archambeau, P., and Erpicum, S.: Low-cost sensor system based on LoraWAN for monitoring water distribution systems, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18824, https://doi.org/10.5194/egusphere-egu2020-18824, 2020.

EGU2020-20102 | Displays | GI4.4

Detection and understanding of water quality deviation events in the drinking water supply network of the Poblenou Sector (Barcelona), Spain

Mireia Plà-Castellana, Julia Roselló-Cano, Alícia Maestro, Jordi Raich-Montiu, and Miquel Paraira

Monitoring critical drinking water points in the water distribution system of Barcelona (Catalonia, Spain) is an increasing concern. The control of several quality parameters as free chlorine, total organic carbon (TOC), conductivity, turbidity, temperature, colour, pressure and flow are necessary to ensure a supply of safe and clean drinking water to consumers.

The aim of this project is to investigate the consequences of alterations detected in the water distribution system, to find the focus of occurrences and controlling them to provide a better drinking water quality to Barcelona citizens.

Barcelona procures drinking water to its citizens via two main water sources: Ter and Llobregat Rivers. They have intrinsic quality differences and they must be treated in different ways. With the purpose of controlling and investigating how these differences impact the water quality supplies, two s::can sensor systems were installed in the Poblenou District (Barcelona). The first one (nano::station) was installed in a drinking water distribution pipe, and the second one (pipe::scan) was installed in a domestic water supply network. Both systems were situated in the same drinking water confluence sector in order to compare the data recorded and to visualise water quality changes. More than 20 events were recorded, analysed and classified according to whether the alteration was due to an occasional event in the domestic water supply or to an external incident from the water distribution system. Some detected events were related to an increase of temperature, a rise of water demand, the water origins or changes in pressure.

One important event recorded by the installed probes was an increase of temperature, directly associated with an augment of total organic matter (TOC) at the beginning of summer (June 2018). A great rise of TOC would be the causer of high consumption of free chlorine that it could be hazardous for human health if there is not enough chlorine dissolved in water. Due to this temperature increment (from 15°C to 23°C in a few days), the minimum level of chlorine (less than 0.2 mg/L) was registered in the Poblenou Sector.

Nano::station and pipe::scan sensor systems are excellent tools as on-line water quality controllers. These kinds of sensors can record variations occurring every two minutes, giving a great perception of the events that are happening at different points of the drinking water city-wide network.

How to cite: Plà-Castellana, M., Roselló-Cano, J., Maestro, A., Raich-Montiu, J., and Paraira, M.: Detection and understanding of water quality deviation events in the drinking water supply network of the Poblenou Sector (Barcelona), Spain, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20102, https://doi.org/10.5194/egusphere-egu2020-20102, 2020.

EGU2020-20499 | Displays | GI4.4

Development of a multi-element method using an ICP-QQQ-MS to characterize the chemical status of surface water bodies

Vera Schmitt, Henning Schroeder, Nadine Belkouteb, Julia Arndt, Jan Wiederhold, and Lars Duester

An instantaneous assessment of the chemical status of surface water bodies provides the ability to better predict the water quality, react in time, and be able to backtrack sources. Also, it is widely accepted that knowledge of the natural chemistry of surface waters is fundamental for identifying anthropogenic pollution (Menzie et al., 2009). The chemical composition of water bodies is controlled by various factors (i.e. atmospheric, geological, biological, etc.). However, the main impact beside anthropogenic pollution is the geological background (e.g. Filella et al., 2014).

To monitor and understand the chemical status it is necessary to measure, with the best possible reliability, a wide spectrum of inorganic analytes. Inductively coupled plasma mass spectrometry (ICP-MS) is widely-accepted as versatile instrument in trace element determination due to its low detection limits, fast multi-element ability and wide dynamic range. The appearance of various polyatomic interferences, low analyte abundance and low sensitivity due to high ionization energy are major challenges in accomplishing precise, routine suitable, multi-element analysis to quantify all target elements which often requires complex pre-measurement treatments. The triple quadrupole ICP-MS (ICP-QQQ-MS; resp. ICP-MS/MS) is a promising tool to overcome some of these limitations. Therefore, our aim was to create a multi-element method with about 65 major and trace elements for surface water. In contrast to existing ICP-MS methods, a single-run-measurement of all analytes is envisaged, including also challenging elements like B, C, P, S, Hg, and REE without a pre-concentration or matrix removal step. The development exhibits very low Limits of Quantification for Rhine and Moselle river water (e.g. REE < 10 ppt).

Our method is based on certified reference material, single element standards (traceable to NIST) and samples from the Rhine and Moselle rivers (Germany). Single element optimized methods were adjusted to the multi-element monitoring purpose. We optimized different collision/reaction cell modes (O2, He, H2) to eliminate isobaric, polyatomatic and/or double charged interferences and the multi-element calibration cross check for memory effects and uncertainties. Hence, we developed a powerful method for surface water quality monitoring and hydro-chemical fingerprinting adaptable to the specific user requirements.

Filella, M., Pomian-Srzednicki, I., Nirel, P.M., 2014. Development of a powerful approach for classification of surface waters by geochemical signature. Water Res 50, 221-228.

Menzie, C.A., Ziccardi, L.M., Lowney, Y.W., Fairbrother, A., Shock, S.S., Tsuji, J.S., Hamai, D., Proctor, D., Henry, E., Su, S.H., 2009. Importance of considering the framework principles in risk assessment for metals. Environ. Sci. Technol. 43, 22, 8478-8482.

How to cite: Schmitt, V., Schroeder, H., Belkouteb, N., Arndt, J., Wiederhold, J., and Duester, L.: Development of a multi-element method using an ICP-QQQ-MS to characterize the chemical status of surface water bodies , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20499, https://doi.org/10.5194/egusphere-egu2020-20499, 2020.

EGU2020-21613 | Displays | GI4.4

Combined vector network analyzer and impedance analyzer for broadband determination of complex permittivity spectrum of glass beads with talc

Justyna Szerement, Hironobu Saito, Kahori Furuhata, Shin Yagihara, Agnieszka Szypłowska, Marcin Kafarski, Arkadiusz Lewandowski, Andrzej Wilczek, Aleksandra Woszczyk, and Wojciech Skierucha

Soil complex dielectric permittivity is frequency dependent. At low frequencies soil dielectric spectrum exhibits relaxation effects mainly due to interfacial phenomena caused by water strongly bounded to solid phase particles surfaces, double-layer effects and Maxwell-Wagner effect. At frequencies of several GHz and above, the influence of dielectric dispersion of free water dipoles can be observed.  Since dielectric soil moisture meters operate at frequencies from kHz up to several GHz, their output can be affected by these phenomena.

Currently, there is a variety of commercial sensors that operate at various frequencies from kHz up to several GHz. Most popular are TDR sensors with frequency band up to 1-2 GHz and capacitance/impedance sensors that operate at a single frequency usually from the range
1-150 MHz. Therefore, the knowledge of the broadband complex dielectric permittivity spectrum can help to improve the existing and develop new methods and devices for soil moisture and salinity estimation. Also, accurate characterization of complex dielectric permittivity spectrum of porous materials in the broadband frequency range is required for modeling of dielectric properties of materials in terms of moisture, salinity, density, mineralogy etc.

The aim of the study was to measure the complex dielectric permittivity of glass beads with 5% talc moistened with distilled water and saline water (electrical conductivity of 500, 1000, 1500 mS/m). The experiment was carried out using a seven-rod probe connected to an impedance analyzer (IA) and a vector network analyzer (VNA) using a multiplexer in the frequency range from 40Hz to 110MHz (IA) and 10MHz to 500MHz (VNA). The glass beads (90-106 µm, Fuji Manufacturing Industries, Japan) with 5% talc (Sigma Aldrich) in 4 different moisture and 4 different salinity values were examined. The results obtained from the IA and the VNA were combined and modeled with complex conductivity and dielectric permittivity model. The influence of water content and electrical conductivity on broadband complex dielectric spectra and the fitted model parameters was examined.

 

The work has been supported by the National Centre for Research and Development, Poland, BIOSTRATEG3/343547/8/NCBR/2017.

How to cite: Szerement, J., Saito, H., Furuhata, K., Yagihara, S., Szypłowska, A., Kafarski, M., Lewandowski, A., Wilczek, A., Woszczyk, A., and Skierucha, W.: Combined vector network analyzer and impedance analyzer for broadband determination of complex permittivity spectrum of glass beads with talc, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21613, https://doi.org/10.5194/egusphere-egu2020-21613, 2020.

EGU2020-21899 | Displays | GI4.4

Simulating irradiance of water layers of natural reservoirs by solar radiation in various spectral ranges

Natalia Darozhka, Victar Dziomin, Ilya Bruchkouski, Alexander Svetashev, Leonid Turishev, Siarhei Umreika, and Siarhei Barodka

Software has been elaborated enabling to numerically simulate both the irradiance of the reservoir surface from total (direct and diffused) solar radiation with λ = 280 - 800 nm under various conditions (season, zenith angle, cloud cover, aerosol parameters, etc.) and the radiation propagation processes in the aquatic environment including the irradiance of water layers at various depths.
The numerical model employs the discrete ordinate method, implemented in a series of software packages that are in the public domain (DISORT, libRadtran, etc.), as well as the corresponding databases of atmospheric and underlying surface parameters.
To simulate the propagation processes of the solar radiation in aquatic environment, a special database has been developed, containing reference data, orbital observations, and data obtained from instrumental monitoring of surface reservoirs in Belarus maintained by the National Ozone Monitoring Research and Education Center of the Belarusian State University (NOMREC BSU) over many years as part of national environmental studies.
The program combines atmospheric and water modules being able to function both jointly and separately thus allowing one to use spectral irradiance or integrated signals experimentally measured by ground-based devices and immersion photometric systems to validate the results of numerical calculations and model calibration.
Special attention was paid to the propagation of biologically active solar radiation (that is UV-B, UV-A and PAR) in the aquatic environment.
Irradiance of water layers by UV radiation and estimation of the corresponding doses of the main biological effects, in particular DNA, are of special interest due to poor knowledge in this field.
Moreover, in the UV range (if compared with the visible range), under significant radiation scattering and absorption by the turbid aquatic environment of surface water bodies, the interpretation and numerical simulation of the transmission function appear to be not quite a trivial task.
A theoretical research on this problem was added with special laboratory and field experiments.
An experimental study of the irradiation levels of various deep-water layers was conducted in the Naroch group lakes (Naroch, Myastro, Malye Shvakshty, Bolshye Shvakshty, Beloye, and Batorino) using a PionDeep immersion photometer designed at NOMREC BSU.
The results showed the presence of well detected UV-B radiation intensities in the lake of Naroch at sufficiently large depths of ~ 15 m.
 “Immersion” measurements were also carried out at various points in the waters of the Myastro, Malye Shvakshty, Bolshye Shvakshty, Beloye, and Batorino lakes.
The measurements were made under various cloud cover and water surface conditions. Distances from the coast varied within 200−2200 m.
To refine the model parameters a series of laboratory measurements of the transmission of natural and model water  samples in a spectral range of λ = 200–700 nm was conducted. At that the absorption spectra of natural and model water bodies, both full-scale and at various stages of filtration, were analyzed.
The numerical simulation exploiting the refined model of UV transparency and irradiances of water layers at various depths was in a good agreement with experimental data.

How to cite: Darozhka, N., Dziomin, V., Bruchkouski, I., Svetashev, A., Turishev, L., Umreika, S., and Barodka, S.: Simulating irradiance of water layers of natural reservoirs by solar radiation in various spectral ranges, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21899, https://doi.org/10.5194/egusphere-egu2020-21899, 2020.

EGU2020-20453 | Displays | GI4.4

Hybrid energy module for experiments and studies in remote locations

Misha Krassovski, Jeffery Riggs, Chris Tavino, Stan Wullschleger, and Susan Heinz

Increased concerns about regional and global climate change in recent decades has led to a significant expansion of monitoring, observational, and experimental sites in remote areas of the world. During this same time, advances in technology and availability of low-power equipment, have allowed increasingly sophisticated measurements with an increasingly wide variety of instruments, sensors, and sensor networks. However, the deployment and use of these technologies in remote locations is restricted not only by harsh environmental conditions, but by the availability of electrical power and communication options. With this presentation we would like to share our experience of designing and building hybrid energy (solar and wind) module that can be used to provide power and communication capabilities for remote installations.

How to cite: Krassovski, M., Riggs, J., Tavino, C., Wullschleger, S., and Heinz, S.: Hybrid energy module for experiments and studies in remote locations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20453, https://doi.org/10.5194/egusphere-egu2020-20453, 2020.

EGU2020-3639 | Displays | GI4.4 | Highlight

PLANTENNA: 3D-sensor networks monitoring plant environment. An application for fruit frost protection

Marie-Claire Ten Veldhuis, Bas Van de Wiel, Qinwen Fan, and Peter Steeneken

Environmental field conditions are highly variable in three-dimensions and unsuitable to be probed by a single sensor or weather station. In PLANTENNA, a team of electronics, precision and microsystems engineers and plant and environmental scientists collaborate to develop and implement 3D-sensor networks that measure plant and environmental parameters at high resolution and low cost. A first problem we aim to tackle in the field is 3D-monitoring of fruit farms for detection and mitigation of fruit frost damage. The objectives are two-fold:

- To quantify the time-dependent effects of frost mitigation measures on the 3D temperature profile, and to determine the resulting plant-physiological response to get a better understanding of the underlying mechanisms leading to frost damage.

- To develop low-cost, low power, wireless, distributed sensor networks, with automated mathematical data handling to give real-time visualization of subzero temperature regions as decision support system for the farmer.

Field implementation: A fruit farm will be equipped with optical fibre cables for Distributed Temperature Sensing, along horizontal and vertical profiles in the field. This will reveal how cooling penetrates the canopy as a function of time, and how this is influenced by changing atmospheric conditions and mitigation efforts. Detailed temperature monitoring is related to spatio-temporal physiological monitoring at the level of individual trees.

In a next step, the cables will be replaced by a 3D-network of  temperature sensors. The aim is to develop an accurate (±0.5°C accuracy with a resolution << 0.1°C), low cost sensor with ultra-low power consumption (~ 100 nW). The sensor is based on a PCB-based node that consists of a PV module to collect solar energy, a power management integrated circuit (PMIC), a supercapacitor to store energy, a temperature sensor, a microcontroller (µC), a timing control unit (TCU) to enable/disable the system, and a radio frequency IC (RFIC) + antenna to transmit data to the network. To reduce energy consumption, it should operate in low-power “sleep mode” as much as possible, while still being able to capture sudden temperature changes as by ventilator activation: the sensor must decide when to “wake up” and how frequently to measure. The often “power-hungry” MCU and RF radio should operate in an event-driven mode and only “awakened” when the sensor detects a temperature change above a certain threshold.
We chose LoRa for its low power consumption and long-distance capability, which is a perfect match with our application.

How to cite: Ten Veldhuis, M.-C., Van de Wiel, B., Fan, Q., and Steeneken, P.: PLANTENNA: 3D-sensor networks monitoring plant environment. An application for fruit frost protection, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3639, https://doi.org/10.5194/egusphere-egu2020-3639, 2020.

GI4.5 – Arctic observations: data collection, management, and user engagement

EGU2020-22498 | Displays | GI4.5 | Highlight

Developments in Polar Data Management 2006 – 2019 and Beyond: standardization and community-building in support of enhanced interoperability

Peter L. Pulsifer, Sandra McCubbin, Stein Sandven, and Mark A. Parsons

A consortium of polar data coordinating bodies has recently hosted a number of useful workshops and events to foster collaboration between individuals, institutions, projects and organizations. These events have built on polar data coordination efforts including progress made during the International Polar Year, focused workshops in 2016, 17, and 18, and three Polar Data Forum meetings (2013,15,19).  

 

These and other activities have identified a need for continued community development and detailed technical collaboration in order to advance Polar Data Management. Technical activity has centred on achieving federated search through the exchange of standardised, well formatted discovery metadata. This is an important first step towards an interconnected polar data system and important gaps and mitigation have been identified at the levels of standardisation, exchange protocols, and eventually semantic annotation of datasets.

 

These activities have been and will continue to be organized by a group of coordination bodies including the IASC-SAON Arctic Data Committee, the Southern Ocean Observing System, Standing Committee on Antarctic Data Management, GEO Cold Regions Initiative, Polar View, Arctic Portal, ELOKA, Canadian Consortium on Arctic Data Interoperability, U.S. Inter-agency Arctic Research Policy Committee Arctic Data Sub-Team, and the WMO Global Cryosphere Watch.

 

As a contribution to these international efforts, in January 2020, the European Union Horizon 2020 project CAPARDUS was established as a coordination and support action with the objective to establish a comprehensive framework for development, understanding and implementation of Arctic standards with focus on environmental topics and related data. The framework will integrate standards used by communities active in the Arctic and polar regions including research and services, Indigenous and local communities, commercial operators and governance bodies. Development of standards is important for many technologies and services (e.g. federated search) that can bring broad social and economic benefits within and beyond the Arctic region.

 

In this presentation we first provide a synthesis of more than a decade and a half of activity and development in polar data management and interoperable data sharing.  Results from this analysis reveal two primary areas of successful developments: i) social and organizational including data policy, building working relationships, and funding cyberinfrastructure ; ii) technical developments in federated search, semantic interoperability, and use of web services.  Patterns, advancements and development gaps are identified and discussed.  Secondly, we present an overview of the first quarter of activity under the CAPARDUS project, including a preliminary model aimed and enhancing appropriate levels of standardization in the polar data community.

How to cite: Pulsifer, P. L., McCubbin, S., Sandven, S., and Parsons, M. A.: Developments in Polar Data Management 2006 – 2019 and Beyond: standardization and community-building in support of enhanced interoperability, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22498, https://doi.org/10.5194/egusphere-egu2020-22498, 2020.

EGU2020-22420 | Displays | GI4.5 | Highlight

A Roadmap for Arctic Observing and Data Systems

Jan Rene Larsen and Sandy Starkweather

A changing Arctic

In recent decades, sustained observations of Arctic environmental and socio-economic systems have revealed a pace, magnitude, and extent of change that is unprecedented by many measures. These changes include rapid depletion of the cryosphere, shifts in ecological communities that threaten biodiversity and increasing challenges to food security and resilience across northern communities.

 

The Sustaining Arctic Observing Networks (SAON)

SAON is a joint initiative of the Arctic Council and the International Arctic Science Committee (IASC). It was created to strengthen multinational engagement in and coordination of pan-Arctic observing. SAON’s intent is to unite Arctic and non-Arctic countries and Indigenous Peoples in support of a systematic network of activities through structured facilitation.

 

A Roadmap for Arctic Observing and Data Systems (ROADS)

In its recent strategic plan, SAON identified the need for a Roadmap for Arctic Observing and Data Systems (ROADS) to set a course for the needed system and to specify how the various partners and players are going to collectively work towards getting it there. The purpose of ROADS is to stimulate multinational resource mobilization around specific plans with clear value propositions, to serve as a tool for the joint utilization of Indigenous Knowledge and science, to coordinate engagement and to ensure that maximal benefits are delivered. A well-defined assessment process is required to establish a communal view of “societal benefit”, and a key tool for such assessment will be The International Arctic Observing Assessment Framework (IAOAF) following the First Arctic Science Ministerial.

Continuing multinational coordination through SAON was endorsed by the Second Arctic Science Ministerial in their Joint Statement with an emphasis on: “moving from the design to the deployment phase of an integrated Arctic observing system”.

 

Essential Arctic Variables

SAON has identified the essential variable strategy as a best practice for supporting network development. The approach is conceptually holistic, yet can proceed step-wise as essential variables achieve readiness. ROADS will be organized around Essential Arctic Variables (EAVs). These are conceptually broad observing categories (e.g. “sea ice”) identified for their criticality to achieving Arctic societal benefit. EAVs are defined by their observing system requirements (e.g. spatial resolution, frequency, coverage, accuracy), which are technology-neutral and should transcend specific observing strategies, programs or regions. They are implemented through specific recommendations based on best available technology and practices.

How to cite: Larsen, J. R. and Starkweather, S.: A Roadmap for Arctic Observing and Data Systems, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22420, https://doi.org/10.5194/egusphere-egu2020-22420, 2020.

EGU2020-20091 | Displays | GI4.5

INTAROS synthesis of gap analysis of the existing Arctic observing systems

Roberta Pirazzini, Michael Tjernström, Stein Sandven, Hanne Sagen, Torill Hamre, Carsten Ludwigsen, Agnieszka Beszczynska-Möller, David Gustafsson, Georg Heygster, Mikael Sejr, Andreas Ahlstrøm, Francisco Navarro, Mathias Goeckede, Donatella Zona, Erik Buch, Mathilde Sorensen, and Thomas Soltwedel

A comprehensive assessment of a substantial subset of Arctic observing systems, data collections and satellite products across scientific disciplines was carried out in INTAROS, also including data repositories and a brief scientific gap analysis. The assessments cover a multitude of aspects such as sustainability, technical maturity and data handling for the entire chain from observation to users, including metadata procedures and availability to data. Community based environment monitoring programs were surveyed and assessed separately; they do not form part of the present assessment.

The assessed observing systems were first ranked according to general sustainability and other aspects, were analyzed subsequently. While the range of sustainability is large, it was found that high scores on all other aspects, such as for data handling and technical maturity, are more likely for systems with high sustainability. Moreover, many systems with high sustainability, as well as advanced systems for data handling and availability in place, resulted from national commitments to international monitoring or infrastructure programs, several of which are not necessarily particular to the Arctic.

Traditionally, terrestrial and atmospheric observation network assessments build on the network concept with a “comprehensive” level including all observations, a “baseline” level of an agreed subset of sustained observations, and a “reference” level, with observations adhering to specific calibrations and traceability criteria. Examples from atmospheric observations are the “comprehensive” global GCOS radiosounding network, the “baseline” GUAN (GCOS Upper Air Network) and “reference” GRUAN (GCOS Reference Upper Air Network) networks. With the lack of in-situ observations especially from the Arctic Ocean and the logistical difficulties to deploy new stations, it was concluded that this concept does not work well in the Arctic.

In summary, we recommend that:

  • advancement in Arctic observing should be done in international global or regional programs with well-established routines and procedures, rather than to invest in new Arctic-specific programs
  • investments in new instruments and techniques be done at already established sites, to benefit interdisciplinary studies and optimize infrastructure costs
  • more observations be based on ships of opportunity and that a subset of ocean, sea-ice and atmosphere observations always be made on all research expeditions, regardless of their scientific aim
  • the funding structures for science expeditions is reviewed to maintain, and preferably increase, the number of expeditions and to safeguard funding for appropriate data handling and storage
  • observing-network concept for the atmosphere over the Arctic Ocean is revised, so that coupled reanalyses represent the “comprehensive level”, satellite observations complemented with available in-situ data is the “baseline level”, while scientific expeditions is the “reference level”. This requires substantial improvements in reanalysis, better numerical models and data assimilation, better satellite observations and improved data handling and accessibility for scientific expeditions.

How to cite: Pirazzini, R., Tjernström, M., Sandven, S., Sagen, H., Hamre, T., Ludwigsen, C., Beszczynska-Möller, A., Gustafsson, D., Heygster, G., Sejr, M., Ahlstrøm, A., Navarro, F., Goeckede, M., Zona, D., Buch, E., Sorensen, M., and Soltwedel, T.: INTAROS synthesis of gap analysis of the existing Arctic observing systems, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20091, https://doi.org/10.5194/egusphere-egu2020-20091, 2020.

EGU2020-20559 | Displays | GI4.5 | Highlight

Mapping Arctic Observing Systems and In Situ Data Collections

Torill Hamre, Frode Monsen, Hanne Sagen, Tor I. Olaussen, Florian Geyer, and Roberta Pirazzini

Climate change in the Arctic is significant and will have far-reaching consequences for marine life and sustainable societal and industrial development in this region. Sustained direct (in situ) measurements of key physical and biogeochemical parameters in Arctic waters are required to estimate the state and monitor changes in the marine environment. Since in situ data is most frequently collected in research projects funded by national, regional or international programmes, there is no common overview of what data are collected in which area, for which time period, by which organisation, or where the data are stored. The H2020 INTAROS project has conducted a survey of Arctic in situ observing systems, in situ and remote sensing data collections. Based on the questionnaires from this survey we have developed a user-friendly web-based system for collecting and maintaining information about Arctic in situ observing systems and data collections in a project funded by the Norwegian Ministry of Climate and Environment. This system, called arcmap, is developed using open source technologies and frameworks, such as wq (https://wq.io/) and Django REST (https://www.django-rest-framework.org/). Arcmap enables users to register and maintain information about their Arctic in situ observing systems and data collections. The information is stored in a relational database, which offers a flexible query language for extracting subsets and aggregates of information based on user defined criteria. Building on this database, statistics can be generated on for example spatial and temporal coverage, parameters observed and targeted application areas, nationality of owners of observing systems and data collections, funding sources and periods, maturity of data management. Using these statistical measures different aspects of sustainability for current and planned Arctic observing systems can be analysed. This allows us to identify patterns and gaps in collection of important environmental variables and to follow the evolution of observing systems over time. The presentation will focus on the current functionality of arcmap and outline possible future enhancements.

How to cite: Hamre, T., Monsen, F., Sagen, H., Olaussen, T. I., Geyer, F., and Pirazzini, R.: Mapping Arctic Observing Systems and In Situ Data Collections, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20559, https://doi.org/10.5194/egusphere-egu2020-20559, 2020.

EGU2020-22212 | Displays | GI4.5

INTAROS joint assessment of scientific and community-based observation programs

Finn Danielsen, Roberta Pirazzini, Hajo Eicken, Maryann Fidel, Lisbeth Iversen, Noor Johnson, Olivia Lee, Michael K. Poulsen, Peter L. Pulsifer, Hanne Sagen, and Stein Sandven

The dramatic changes occurring in the Arctic due to the global warming generate feedbacks on global circulation and midlatitude climate and, at the local scale, pose challenges to Arctic populations and infrastructures and threaten the Arctic fauna and flora. Observations in the Arctic are needed to understand the ongoing geophysical and socio-ecological processes and changes, to plan adaptation strategies, and to sustainably manage the environment. A joint effort from the scientific and societal communities is necessary to monitor relevant phenomena in such a vast and poorly accessible area of the globe.

The integration of citizen and science observations is envisioned by the Sustaining Arctic Observing Networks (SAON) as a key element of the Roadmap for a comprehensive long-term pan-Arctic Observing and Data System (ROADS) that serves societal needs. Often, however, the different language and methodology adopted by scientific and non-scientific communities hamper the exchange and usability of the available observations. In the EU INTAROS project, metadata on community-based and scientific observing programs were collected using a common questionnaire in order to assess gaps and strengths in the observing systems.

The assessment revealed that the community-based observations rarely belong to long-term sustained programs, and suffer from lack of long-term preservation strategies more severely than science-based observing systems. On the other hand, many science-based marine observations are collected only during the summer season, while community-based observations are less prone to temporal gaps. Community-based monitoring efforts can help increase observational coverage in space and time with often low-cost approaches, while also adding value through the introduction of holistic perspectives – such as Indigenous knowledge-based – into the observing process.

Our analysis demonstrated that, despite the differences in method and language between community- and science-based programs, the adopted assessment methodology enables the comparison and, thus, the integration of the metadata (that e.g. describe frequency of observations, locations, types of variables observed etc.) pertaining to community and science-based observing systems.

How to cite: Danielsen, F., Pirazzini, R., Eicken, H., Fidel, M., Iversen, L., Johnson, N., Lee, O., Poulsen, M. K., Pulsifer, P. L., Sagen, H., and Sandven, S.: INTAROS joint assessment of scientific and community-based observation programs, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22212, https://doi.org/10.5194/egusphere-egu2020-22212, 2020.

EGU2020-22199 | Displays | GI4.5

The Norwegian Scientific Data Network, a distributed electronic research infrastructure

Øystein Godoy, Torill Hamre, Stein Tronstad, Markus Fiebig, Helge Sagen, and Lara Ferrighi

The Norwegian Scientific Data Network (NorDataNet) is a national e-infrastructure building on the legacy of the International Polar Year. Initially it is focusing on geoscience and establishing interoperability interfaces between existing national data repositories in the areas of discovery metadata and data as well as on harmonised data documentation following the FAIR guiding principles. The technical foundation of NorDataNet is built on data documentation standards, standardised interoperability interfaces and semantic resources. This is now in place and preliminary functionalities are available. These includes the ability to discover and access datasets across the data repositories integrated, as well as visualisation and transformation of datasets served using the requested documentation standards and interfaces. Bottlenecks and achievements while working towards FAIR compliant data and data centres interoperability will be presented.

How to cite: Godoy, Ø., Hamre, T., Tronstad, S., Fiebig, M., Sagen, H., and Ferrighi, L.: The Norwegian Scientific Data Network, a distributed electronic research infrastructure, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22199, https://doi.org/10.5194/egusphere-egu2020-22199, 2020.

EGU2020-22427 | Displays | GI4.5

The Observation Facility Catalogue – an overview of the SIOS research infrastructure on Svalbard

dariusz ignatiuk, Inger Jennings, Lara Ferrigni, Øystein Godøy, Shridhar Jawak, Heikki Lihavainen, Bo Andersen, and Christiane Hübner

Svalbard Integrated Arctic Earth Observing System (SIOS) is an international consortium to develop and maintain a regional observing system in Svalbard and the surrounding waters. SIOS brings observations together into a coherent and integrated observational programme that will be sustained over a long period. Within SIOS, researchers can cooperate to access instruments, acquire data and address questions that would not be practical or cost effective for a single institution or nation alone. By bringing many types of observations together and asking questions about how these observations are influenced by each other, SIOS generates new insights about the Svalbard region’s role in the Earth system.  Thus, SIOS offers unique opportunities for research and the long-term acquisition of fundamental knowledge about global environmental change.

SIOS facilitates access to Earth System Science (ESS) data from Svalbard through a free and open data portal that enables the users to search, retrieve, visualise, transform, and harvest ESS data relevant to Svalbard stored in the distributed data centres of SIOS partners. The Observation Facility Catalogue (OFC) is a part of SIOS data portal which allows collecting and sharing information about research infrastructures distributed in Svalbard.

The OFC gives an overview of existing, planned and historic observation facilities,which collect SIOS data. An observation facility can be one instrument or a collection of instruments. The annotation is standardised based on WMO standards as far as possible, in order to make entries unambiguous and interoperable internationally.

The purpose of the OFC is to make better use of the existing research infrastructure by facilitating the search for given parameters and their location.  In this way, duplication can be avoided and new measurements can be co-located with existing ones. The catalogue has a map interface and advanced search function.  The search interface allows users to search for GCMD keywords or to filter by status, type or observatory.

How to cite: ignatiuk, D., Jennings, I., Ferrigni, L., Godøy, Ø., Jawak, S., Lihavainen, H., Andersen, B., and Hübner, C.: The Observation Facility Catalogue – an overview of the SIOS research infrastructure on Svalbard, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22427, https://doi.org/10.5194/egusphere-egu2020-22427, 2020.

EGU2020-7126 | Displays | GI4.5 | Highlight

Extending the Ice Watch system as a citizen science project for the collection of In-Situ sea ice observations

Ole Jakob Hegelund, Alistair Everett, Ted Cheeseman, Penelope Wagner, Nick Hughes, Marcin Pierechod, Ken Southerland, Philip Robinson, Jennifer Hutchings, Åshild Kiærbech, and Joakim Lillehaug Pedersen

The Ice Watch program coordinates routine visual observations of sea-ice including icebergs and meteorological parameters. The development and use of the Arctic Shipborne Sea Ice Standardization Tool (ASSIST) software has enabled the program to collect over 6 800 records from numerous ship voyages and it is complementary to the Antarctic Sea-ice Processes and Climate (ASPeCt) in the Antarctic. These observations will enhance validation and calibration of data from the Copernicus Sentinel satellites and other Earth Observation missions where the lack of routine spatially and temporally coincident data from the Polar Regions hinders the development of automatic classification products. A critical piece of information for operations and research, photographic records of observations, is often missing. As mobile phones are nearly ubiquitous and feature high-quality cameras, capable of recording accurate ancillary timing and positional information we are developing the IceWatchApp to aid users in supplementing observations with a photographic record.

The IceWatchApp has been funded by the Citizen Science Earth Observation Lab (CSEOL) programme of the European Space Agency and the Polar Citizen Science Collective, which has successfully implemented similar observation projects within atmospherics, biology and marine geosciences, is collaborating in its development. The image database will aid the training of machine learning algorithms for automatic sea ice type classification and provide a mechanism for crowd-sourcing identification through an “ask a scientist” feedback feature. The app will also have the capability to provide near real-time satellite and Copernicus services products back to the user, thereby educating them on Earth Observation, and giving them an improved understanding of the surrounding environment.

 

Keywords: Polar regions, Arctic, Antarctic, data collection, In-Situ measurements, remote sensing, Sea Ice, user engagement, citizen science, Earth Observation.
Abstract: to session 35413

 

How to cite: Hegelund, O. J., Everett, A., Cheeseman, T., Wagner, P., Hughes, N., Pierechod, M., Southerland, K., Robinson, P., Hutchings, J., Kiærbech, Å., and Lillehaug Pedersen, J.: Extending the Ice Watch system as a citizen science project for the collection of In-Situ sea ice observations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7126, https://doi.org/10.5194/egusphere-egu2020-7126, 2020.

EGU2020-20347 | Displays | GI4.5

Implementation of a multipurpose Arctic Ocean Observing System

Stein Sandven, Hanne Sagen, Agnieszka Beszczynska-Möller, Peter Vo, Marie-Noelle Houssais, Mathilde Sørensen, Mikael Kristian Sejr, Matthew Dzieciuch, Peter Worcester, Espen Storheim, Florian Geyer, and Bjørn Rønning

The central Arctic Ocean is one of the least observed oceans in the world. This ice-covered region is challenging for ocean observing with respect to technology, logistics and costs. Many physical, biogeochemical, biological, and geophysical processes in the water column and sea floor under the sea ice are difficult to observe and therefore poorly understood. Today, there are technological advances in platforms and sensors for under-ice observation, which offer possibilities to install and operate sustained observing infrastructures in the Arctic Ocean. The goal of the INTAROS project is to develop integrated observing systems in the Arctic, including improvement of data sharing and dissemination to various user groups. INTAROS supports a number of systems providing data from the ocean in delayed mode as well as in near-real time mode, but only a few operate in the ice-covered areas.

Autonomous observing platforms used in the ice-free oceans such as Argo floats, gliders, and autonomous surface vehicles cannot yet be used operationally in ice-covered Arctic regions. The limitation is because the sea ice prevents these underwater platforms from reaching the surface for satellite communication and geopositioning. To improve the Arctic Ocean Observing capability OceanObs19 recommended ‘to pilot a sustained multipurpose acoustic network for positioning, tomography, passive acoustics, and communication in an integrated Arctic Observing System, with eventual transition to global coverage’. Acoustic networks have been used locally and regionally in the Arctic for underwater acoustic thermometry, geo-positioning for floats and gliders, and passive acoustic. The Coordinated Arctic Acoustic Thermometry Experiment (CAATEX) is a first step toward developing a basin-scale multipurpose acoustic network using modern instrumentation.

To provide secure data delivery, submarine cables are needed either as dedicated cabled observatories or as hybrid cable systems (sharing the cable infrastructure between science and commercial telecommunications), or both combined. Several large-scale cabled observatories existing coastal areas in world oceans, but none on the Arctic Ocean. At OceanObs19 it was recommended to transition (telecom+sensing) SMART subsea cable systems from present pilots to trans-ocean implementation, to address climate, ocean circulation, sea level, tsunami and earthquake early warning, ultimately with global coverage. Cabled observatories, either stand alone or branching from a hybrid system, could provide power and real time communication to support connected water column moorings and sea floor instrumentation as well as docking mobile platforms. Subsea cable developers are looking into the possibility to deploy a communication cable across the Arctic Ocean from Europe to Asia, because this offers a much shorter route compared to the terrestrial cables.

 An international consortium of leading scientists in ocean observing with experience in state-of-the-art technologies on platforms, sensors, subsea cable technology, acoustic communication and data transmission plan to establish a project to implement and test the system based on experience from the CAATEX experiment and other Arctic observing system experiments. The INTAROS project is presently developing a Roadmap for an integrated Arctic Observing System, where multipurpose ocean observing systems will be one component.

How to cite: Sandven, S., Sagen, H., Beszczynska-Möller, A., Vo, P., Houssais, M.-N., Sørensen, M., Sejr, M. K., Dzieciuch, M., Worcester, P., Storheim, E., Geyer, F., and Rønning, B.: Implementation of a multipurpose Arctic Ocean Observing System, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20347, https://doi.org/10.5194/egusphere-egu2020-20347, 2020.

EGU2020-22171 | Displays | GI4.5

Winter Arctic sea ice bottom evolution detected by thermistor string-based ice mass balance buoys (SIMBA)

Bin Cheng, Timo Vihma, Zeling Liao, Ruibo Lei, Mario Hoppmann, Yubao Qiu, Roberta Pirazzini, and Stein Sandven

A thermistor-string-based Snow and Ice Mass Balance Array (SIMBA) has been developed in recent years and used for monitoring snow and ice mass balance in the Arctic Ocean. SIMBA measures vertical environment temperature (ET) profiles through the air-snow-sea ice-ocean column using a thermistor string (5 m long, sensor spacing 2cm). Each thermistor sensor equipped with a small identical heating element. A small voltage was applied to the heating element so that the heat energy liberated in the vicinity of each sensor is the same. The heating time intervals lasted 60 s and 120 s, respectively. The heating temperatures (HT) after these two intervals were recorded. The ET was measured 4 times a day and once per day for the HT.

A total 15 SIMBA buoys have been deployed in the Arctic Ocean during the Chinese National Arctic Research Expedition (CHINARE) 2018 and the Nansen and Amundsen Basins Observational System (NABOS) 2018 field expeditions in late autumn. We applied a recently developed SIMBA algorithm to retrieve snow and ice thickness using SIMBA ET and HT temperature data. We focus particularly on sea ice bottom evolution during Arctic winter.

In mid-September 2018, 5 SIMBA buoys were deployed in the East Siberian Sea (NABOS2018) where snow was in practical zero cm and ice thickness ranged between 1.8 m – 2.6 m. By the end of May, those SIMBA buoys were drifted in the central Arctic where snow and ice thicknesses were around 0.05m - 0.2m and 2.6m – 3.2m, respectively. For those 10 SIMBA buoys deployed by the CHINARE2018 in the Chukchi Sea and Canadian Basin, the initial snow and ice thickness were ranged between 0.05m – 0.1cm and 1.5m – 2.5m, respectively.  By the end of May, those SIMBA buoys were drifted toward the north of Greenland where snow and ice thicknesses were around 0.2m - 0.3m and 2.0m – 3.5m, respectively. The ice bottom evolution derived by SIMBA algorithm agrees well with SIMBA HT identified ice-ocean interfaces. We also perform a preliminary investigation of sea ice bottom evolution measured by several SIMBA buoys deployed during the MOSAiC leg1 field campaign in winter 2019/2020.  

How to cite: Cheng, B., Vihma, T., Liao, Z., Lei, R., Hoppmann, M., Qiu, Y., Pirazzini, R., and Sandven, S.: Winter Arctic sea ice bottom evolution detected by thermistor string-based ice mass balance buoys (SIMBA), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22171, https://doi.org/10.5194/egusphere-egu2020-22171, 2020.

EGU2020-5077 | Displays | GI4.5

Sea level in Thule measured with tide gauge, GNSS-IR and Satellite Altimetry

Trine S. Dahl-Jensen, Shfaqat Abbas Khan, Simon D.P. Williams, Ole B. Andersen, and Carsten A. Ludwigsen

Recent studies show that under the right conditions relative sea level can be measured using GNSS interferometric reflectometry (GNSS-IR). We test the possibility of using an existing GNET GPS station in Thule, Greenland, to measure inter annual changes in sea level by comparing sea level measurements from GNSS-IR with tide gauge observations and satellite altimetry data. GNET is a network of 56 permanent GPS stations positioned on the bedrock around the edge fo the Greenland ice sheet with the main purpose of monitoring ice mass changes. Currently, Thule is the only location in Greenland where we have both a tide gauge and a GPS station that is suitable for sea level measurement covering the same time period for more than a couple of years. If successful a number of other GPS stations are also expected to be suitable for GNSS-IR measurements of sea level. However, they lack the tide gauge station for testing.
We compare the measured sea level with uplift measured using the GPS and modeled from height changes of the Greenland ice sheet as well as sea surface temperatures and modeled sea level changes from gravimetry, in order to investigate the origin of sea level changes in the region.  
 

How to cite: Dahl-Jensen, T. S., Khan, S. A., Williams, S. D. P., Andersen, O. B., and Ludwigsen, C. A.: Sea level in Thule measured with tide gauge, GNSS-IR and Satellite Altimetry, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5077, https://doi.org/10.5194/egusphere-egu2020-5077, 2020.

EGU2020-8496 | Displays | GI4.5

Stable water isotope observations during INTAROS cruises North of Svalbard: links to atmospheric circulation and sea ice processes

Alexandra Touzeau, Harald Sodemann, Hanne Sagen, Mats Anders Granskog, Bonnie Raffel, Nicholas Roden, Espen Storheim, Tor Einar de Lange, Yi-Chun Chen, and Håkon Sandven

Water isotopes measured in ice cores are well-known tracers of paleoclimate variations. The ratio of heavy to light isotope in snow is indeed strongly controlled by the temperature during condensation along the entire airmass transport. This allows the utilization of isotope variability in the water cycle in current climatic conditions, and on weather time scales, to try to pinpoint key events and processes building up (or re-stating) the isotope signature of a given air mass. Because isotopic fractionation occurs every time water changes phase, it is highly beneficial to sample concurrently the different water reservoirs (i.e. seawater, sea ice, snow, rain and vapor) in order to truly understand the processes at work.

Here we present stable water isotope data from two cruises north of Svalbard within the INTAROS project (summer 2018 and summer 2019). During these cruises, vapor isotope composition was measured quasi-continuously on the coast guard icebreaker KV Svalbard. Seawater and precipitation samples were collected continuously throughout the cruises. The 2018 cruise mainly targeted locations within the Marginal Ice Zone north of Svalbard. On the 2019 cruise, sea ice samples and snow samples were collected at 8 ice stations, all the way to the North Pole. The liquid/solid samples were later analyzed at FARLAB at the University of Bergen.

A first analysis of the dataset shows that stable water isotope values vary with air mass origin, with marked differences between '18O-enriched’ air coming from the south-east (Barents Sea) and ‘18O-depleted’ air from the north-west (Inner Arctic) during the second cruise. During the 2019 cruise, vapor in air from the south-east tends to have relatively low d-excess values whereas precipitation is largely at equilibrium with the ambient vapor. This INTAROS dataset will be highly beneficial for studies using (coupled) isotope-enabled models, such as earth system models or high-latitude regional climate models, to validate their representation of the high-latitude water cycle.

 

How to cite: Touzeau, A., Sodemann, H., Sagen, H., Granskog, M. A., Raffel, B., Roden, N., Storheim, E., de Lange, T. E., Chen, Y.-C., and Sandven, H.: Stable water isotope observations during INTAROS cruises North of Svalbard: links to atmospheric circulation and sea ice processes, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8496, https://doi.org/10.5194/egusphere-egu2020-8496, 2020.

EGU2020-22424 | Displays | GI4.5

The INGV Arctic Ionospheric data management system and its synergy with the Italian NADC

Emanuele Pica, Vincenzo Romano, Carlo Marcocci, Claudio Cesaroni, and Ingrid Hunstad

The Space Weather effects on the ionosphere considerably affect several modern technology infrastructures, such as telecommunication systems, power networks and in general systems relying on satellite navigation. The polar regions have always been a natural laboratory for the analysis of these phenomena and regular observations are required to gain better knowledge about the relationships between the ionized atmosphere and the others atmospheric layers as well as to provide support to civil aviation and maritime for the safety of the polar routes.

The Istituto Nazionale di Geofisica e Vulcanologia (INGV) has a long history in acquiring ionospheric data in the polar regions and currently operates in the Arctic two permanent observatories in Svalbard (Ny-Ålesund and Longyearbyen), Norway, equipped with three GNSS receivers for scintillation and TEC measurement. An additional receiver will be installed soon at the Thule Air Base (Greenland).

The uninterrupted data production from these instruments and the necessity to provide near real-time access to this information makes it necessary to develop suited procedures and ad-hoc IT infrastructures. To address these needs the INGV designed the SWIT system (Space Weather Information Technology) for data management and the web-platform eSWua (electronic Space Weather upper atmosphere) for data dissemination. With regard to the Arctic region, the information-flow from Svalbard stations is provided by optical fibre connections and the SWIT-DBMS operates the ingestion of this data at the INGV central repository within 15 minutes or less. The eSWua website offers a GUI for near real-time and historical data visualization, while web-based tools and a RESTful web-service will provide free access to the data at different processing levels. The planning and design of this infrastructure takes advantage of the experience gained from ongoing projects like the NADC (the Italian National Antarctic Data Center).

In this paper the state of the art of the INGV Arctic and Antarctic data management system for the Ionospheric and space weather data and the efforts undertaken to improve the access and availability of these information are presented and discussed.

How to cite: Pica, E., Romano, V., Marcocci, C., Cesaroni, C., and Hunstad, I.: The INGV Arctic Ionospheric data management system and its synergy with the Italian NADC, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22424, https://doi.org/10.5194/egusphere-egu2020-22424, 2020.

EGU2020-9543 | Displays | GI4.5 | Highlight

Data collections of ESA DUE GlobPermafrost and ESA CCI+ Permafrost

Annett Bartsch and the ESA DUE GlobPermafrost and ESA CCI+ Permafrost Teams

A Permafrost Information System (PerSys) based on satellite data has been setup as part of the ESA DUE GlobPermafrost project (2016-2019, www.globpermafrost.info). This includes a data catalogue as well as a WebGIS, both linked to the Pangaea repository for easy data access.

The thematic products available include InSAR-based land surface deformation maps, rock glacier velocity fields, spatially distributed permafrost model outputs, land surface properties and changes, and ground-fast lake ice. Extended permafrost modelling (time series) is implemented in the new ESA CCI+ Permafrost project (2018-2021, http://cci.esa.int/Permafrost), which will provide the key for our understanding of the changes of surface features over time. Special emphasis in CCI+ Permafrost is on the evaluation and development of land surface models to gain better understanding of the impact of climate change on permafrost and land-atmosphere exchange. Additional focus will be on documentation of kinematics from rock glaciers in several mountain regions across the world supporting the International Permafrost Association (IPA) action group ‘rock glacier kinematics as an essential climate variable’.

We will present the Permafrost Information System including the time series (2003-2017) of the first version of ground temperatures and active layer thickness for the entire Arctic from the ESA CCI+ Permafrost project. Further on, details on the user requirements collection process will be provided. Ground temperature is calculated for 0, 1m, 2m, 5m, and 10 m depth and has been assessed based on a range of borehole data. A survey regarding data repositories containing for validation relevant borehole data has been conducted. The records have been evaluated for the project purpose and harmonized. The resulting database will be eventually also made publicly available.

How to cite: Bartsch, A. and the ESA DUE GlobPermafrost and ESA CCI+ Permafrost Teams: Data collections of ESA DUE GlobPermafrost and ESA CCI+ Permafrost, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9543, https://doi.org/10.5194/egusphere-egu2020-9543, 2020.

EGU2020-13842 | Displays | GI4.5

Integrating and assessing Arctic glacier thickness data into Glacier Thickness Database (GlaThiDa) Version 3.0

Ethan Welty, Francisco Navarro, Johannes Fürst, Isabelle Gärtner-Roer, Kathrin Naegeli, Johannes Landmann, Matthias Huss, Thomas Knecht, Horst Machguth, and Michael Zemp

GlaThiDa is an internationally collected, standardized dataset of glacier thickness from in-situ and remotely sensed observations, based on data submissions, literature review, and airborne data from NASA's Operation IceBridge. GlaThiDa is a contribution to the working group on ‘glacier ice thickness estimation’ formed under the auspices of the International Association of Cryospheric Sciences (IACS). The database is hosted by the World Glacier Monitoring Service (WGMS). GlaThiDa is structured in three data tables of different levels of detail, which are linked together by a unique identifier for each glacier survey. The first table (T) is the overview table containing information on the location and area of the surveyed glacier, interpolated mean and maximum glacier-wide thickness and their reported uncertainties, the survey method and related information, as well as investigator names and source of the data. The second table (TT) includes mean and maximum ice thickness interpolated over surface elevation bands. The third table (TTT) contains the original point measurements, including spatial coordinates, surface elevation, and ice thickness. GlaThiDa was first released in 2014 (version 1.0) and first updated in 2016 (version 2.1). Version 3.0 was released in 2019. In addition to several technical improvements, nearly 3 600 ice-thickness surveys have been added, for a total of 5 181. Most of the new data are for Arctic glaciers, and some of these were collected for the H2020 INTAROS project. Moreover, GlaThiDa was assessed as a core component of the existing Arctic observing system in INTAROS Work Package 2.1 (an assessment of existing Arctic observational capacity and remaining gaps with respect to stakeholders needs). GlaThiDa has great potential as a reference dataset for calibrating and validating regional and global glacier volume estimates.

How to cite: Welty, E., Navarro, F., Fürst, J., Gärtner-Roer, I., Naegeli, K., Landmann, J., Huss, M., Knecht, T., Machguth, H., and Zemp, M.: Integrating and assessing Arctic glacier thickness data into Glacier Thickness Database (GlaThiDa) Version 3.0, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13842, https://doi.org/10.5194/egusphere-egu2020-13842, 2020.

GI4.6 – Progresses and gaps on monitoring of snow and its components at the local-, regional to global scale and its applications to support weather, hydrological and climate science, as well as monitoring of natural hazards

EGU2020-464 | Displays | GI4.6

Non-stationarity of extreme ground snow load in the French Alps

Erwan Le Roux, Guillaume Evin, Nicolas Eckert, Juliette Blanchet, and Samuel Morin

In a context of climate change, assessing trends in hazards related to extreme events is urgent. Specifically current methods to compute European standards for snow load actions on structures do not account for the non-stationarity due to climate change. We present the first analysis of extreme ground snow load trends for the whole French Alps. Our method is based on non-stationary generalized extreme value (GEV) distribution, time derivative of return level and likelihood ratio test. Thanks to Météo France reanalysis and snowpack models, we study moutain massif scale data available every 300m of altitude from 1958 to 2017. We detect an overall decreasing trend for annual maxima of ground snow load between 900m and 2700m, which is significant in the Northwest of the French Alps until 1800m. Despite decreasing return levels, in 2017 half of massifs at altitude 1800m still exceeds standard return levels. We underline the importance of snowpack modelling and limitations of approaches relying on ground snow load computed with snow depth annual maxima and an hypothesis on snow density.

How to cite: Le Roux, E., Evin, G., Eckert, N., Blanchet, J., and Morin, S.: Non-stationarity of extreme ground snow load in the French Alps, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-464, https://doi.org/10.5194/egusphere-egu2020-464, 2020.

EGU2020-1824 | Displays | GI4.6

Measurement inter-comparison of bulk snow density and water equivalent of snow cover with snow core samplers

Leena Leppänen, Juan Ignazio Lopez-Moreno, Bartłomiej Luks, Ladislav Holko, Ghislain Picard, Alba Sanmiguel-Vallelado, Esteban Alonso-González, David Finger, Ali Nadir Arslan, Katalin Gillemot, Aynur Sensoy, Arda Sorman, Cansaran Ertaş, Charles Fierz, Steven Fassnacht, and Christoph Marty

Manually collected snow data can be considered as ground truth for many applications, such as climatological or hydrological studies. Water equivalent of snow cover (SWE) can be manually measured by using a snow tube or snow cylinder to extract a snow core and measure the bulk density of the core by weighing it. Different snow core samplers and scales are used, but they all use the same measurement principle. However, there are various sources of uncertainty that have not been quantified in detail. To increase the understanding of these errors, different manual SWE measurement devices used across Europe were evaluated within the framework of the COST Action ES1404 HarmoSnow. Two field campaigns were organized in different environments to quantify uncertainties when measuring snow depth, snow bulk density and SWE with core samplers. The 1st field campaign in 2017 in Iceland focused on measurement differences attributed to different instrumentation compared with the natural variability in the snowpack, and the 2nd field campaign in 2018 in Finland focused on device comparison and on the separation of the different sources of variability. To our knowledge, such a comparison has not previously been conducted in terms of the number of device and different environments.

During the 1st campaign, repeated measurements were taken along two 20 m long snow trenches to distinguish snow variability measured at the plot and at the point scale. The results revealed a much higher variability of SWE at the plot scale, resulting from both natural variability and instrument bias, compared to repeated measurements at the same spot, resulting mostly from error induced by observers or a high variability in the snow depth. Snow Micro Pen sampling showed that the snowpack was very homogeneous for the 2nd campaign, which allowed for the disregarding of the natural variability of the snowpack properties and the focus to be on separating between instrumental bias and error induced by observers. Results confirmed that instrumental bias exceeded both the natural variability and the error induced by observers, even when observers performed measurements with snow core samplers they were not formally trained on. Under such measurement conditions, the uncertainty in bulk snow density estimation is about 5% for an individual instrument and is close to 10% among different instruments. The results showed that the devices provided slightly different uncertainties since they were designed for different snow conditions. The aim of this comparison was not to provide a definitive estimation of uncertainty for manual SWE measurements, but to illustrate the role of the different uncertainty sources.

How to cite: Leppänen, L., Lopez-Moreno, J. I., Luks, B., Holko, L., Picard, G., Sanmiguel-Vallelado, A., Alonso-González, E., Finger, D., Arslan, A. N., Gillemot, K., Sensoy, A., Sorman, A., Ertaş, C., Fierz, C., Fassnacht, S., and Marty, C.: Measurement inter-comparison of bulk snow density and water equivalent of snow cover with snow core samplers, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1824, https://doi.org/10.5194/egusphere-egu2020-1824, 2020.

EGU2020-8028 | Displays | GI4.6

Using the Jupyter Notebook as a Tool for analyzing the EUMETSAT HSAF snow products

Zuhal Akyurek, Kenan Bolat, Cagri Hasan Karaman, and Matias Takala

Snow cover is an essential climate variable directly affecting the Earth’s energy balance, therefore estimating the snow parameters play an important role in hydrological, land surface, meteorological and climate models. Remote sensing provides a good understanding of snow cover monitoring thus several satellite snow products have been developed and disseminated so far.  In this study, Jupyter Notebook as an open source interactive satellite snow products retrieval, visualization and analysis tool has been developed by using Python language. Jupyter Notebook allows easy and straightforward data analysis with the possibility of live interaction and requires little programming knowledge.

The developed tool provides the capabilities of downloading the satellite snow products, georeferencing them and performing spatial analysis like zonal statistics. In this study EUMETSAT HSAF snow products, namely H10 (Snow detection), H13 (Snow Water Equivalent) and H34 (Snow cover) are used. The tool allows user to upload their own region in ESRI shapefile format for spatial and temporal analysis and the uploaded region can be visualized on interactive map via custom interactive widget like ipyleaflet. The cloud percentage for the snow cover product can be selected and daily snow covered area or snow water equivalent change for the uploaded region can be calculated for the selected period. With this tool, it is aimed to retrieve the satellite snow products easily and perform spatial and temporal analysis of snow cover for the area of interest without getting lost in data formats. Therefore, users with little or no knowledge about programming can interact easily with EUMETSAT HSAF snow products. Furthermore, with the high extensibility of Jupyter Notebook, it can also be improved or modified in accordance with the need of the end users.

How to cite: Akyurek, Z., Bolat, K., Karaman, C. H., and Takala, M.: Using the Jupyter Notebook as a Tool for analyzing the EUMETSAT HSAF snow products, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8028, https://doi.org/10.5194/egusphere-egu2020-8028, 2020.

EGU2020-8348 | Displays | GI4.6

Snow Data Assimilation Methods for Hydrological, Land Surface, Meteorological and Climate Models: Results from COST HarmoSnow (2014-2018)

Jürgen Helmert, Aynur Şensoy Şorman, Rodolfo Alvarado Montero, Carlo De Michele, Patricia De Rosnay, Marie Dumont, Samantha Pullen, David Christian Finger, Martin Lange, Ghislain Picard, Vera Potopová, Dagrun Vikhamar-Schuler, and Ali Nadir Arslan
Snow as a major part of the cryosphere is an important component of Earth’s hydrological cycle and energy balance. Understanding the microstructural, macrophysical, thermal and optical properties of the snowpack is essential for integration into numerical models and there is a great need for accurate snow data at different spatial and temporal resolutions to address the challenges of changing snow conditions.
Physical snow properties are currently determined by traditional ground-based measurements as well as remote sensing, over a range of temporal and spatial scales, following considerable developments in instrument technology over recent years. 
Data assimilation (DA) methods are widely used to combine data from different observations with numerical model using uncertainties of observed and modeled variables  to produce an optimal estimate. DA provides a reliable improvement of the initial states of the numerical model and a benefit for hydrological and snow model forecasts.
 
European efforts to harmonize approaches for validation, and methodologies of snow measurement practices, instrumentation, algorithms and data assimilation techniques were coordinated by the European Cooperation in Science and Technology (COST) Action ES1404 “HarmoSnow”, entitled, “A European network for a harmonized monitoring of snow for the benefit of climate change scenarios, hydrology and numerical weather prediction” (2014-2018) .
One of the key objectives of the action was “Advance the application of snow DA in numerical weather prediction (NWP) and hydrological models, and show its benefit for weather and hydrological forecasting as well as other applications.” 
One key result from COST HarmoSnow is a better knowledge about the diversity of usage of snow observations in DA, forcing, monitoring, validation, or verification within NWP, hydrology, snow and climate models. The main parts of this knowledge are retrieved from a COST HarmoSnow survey exploring the common practices on the use of snow observations in different modeling environments. We will show results from the survey and their implications towards standardized and improved usage of snow observations in various data assimilation applications.

How to cite: Helmert, J., Şensoy Şorman, A., Alvarado Montero, R., De Michele, C., De Rosnay, P., Dumont, M., Pullen, S., Finger, D. C., Lange, M., Picard, G., Potopová, V., Vikhamar-Schuler, D., and Arslan, A. N.: Snow Data Assimilation Methods for Hydrological, Land Surface, Meteorological and Climate Models: Results from COST HarmoSnow (2014-2018), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8348, https://doi.org/10.5194/egusphere-egu2020-8348, 2020.

EGU2020-9891 | Displays | GI4.6

Systematic underestimation of snow accumulation rate by stake measurements in central Antarctica

Alexey Ekaykin, Natalia Tebenkova, Vladimir Lipenkov, Arina Veres, Kirill Tchikhatchev, and Andreas Richter

We demonstrate that the accumulation-stake measurements in central Antarctica systematically underestimate the value of the snow build-up due to the compaction of snow layer between the stake base and the snow surface. We have developed two methods to define the corresponding correction to the snow build-up measurements at the stake farm near Vostok station. The first method is based on "Sorge's law" to calculate the rate of thinning of the snow layers using the vertical snow density profile. The second method consists of direct instrumental measurements of this thinning in the field. We have also involved the data of other two independent methods to estimate the snow accumulation rate in the vicinity of Vostok - first, geodetic data on the rate of snow layer sinking and, second, glaciological data from snow pits. The most reliable estimate of the snow accumulation rate in this region is 2.26±0.10 g cm-2 year-1, that is 8±4 % higher than initial (not corrected) value from the accumulation-stake measurements.

How to cite: Ekaykin, A., Tebenkova, N., Lipenkov, V., Veres, A., Tchikhatchev, K., and Richter, A.: Systematic underestimation of snow accumulation rate by stake measurements in central Antarctica, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9891, https://doi.org/10.5194/egusphere-egu2020-9891, 2020.

Water has an essential effect on climate change, global warming, drought, flood and all kinds of living life as a result of the continuous movement between earth and atmosphere. In high latitude and elevated regions of the world, most of the annual total precipitation occurs in the form of snow and snow melting provides the majority of usable water. Due to the large impact of snow cover on water/energy balance, the quantity, spatial and temporal distribution of the snow is very important in the hydrological system.

Turkey is the 4th highest country in Europe, after Andorra, Georgia and Switzerland, with an average elevation of 1140 m. Therefore, snow frequently occurs and may stay on the ground more than half of the year especially in the north, east and central regions. Snowmelt runoff in the mountainous eastern part of Turkey, where large dams are located, is of great importance as it constitutes 2/3 in volume of the yearly total runoff during spring and early summer months. Therefore, determining the amount and timing of snowmelt is of utmost value in order to use the water resources of the country in an optimal manner.

In this study; conceptual snowpack model SNOW-17, which has a common usage in the literature, is applied in a fully distributed manner in the Upper Euphrates Basin. SNOW-17 is a conceptual model using air temperature as the sole index to determine the energy exchange across the snow-air interface. The model results of snowpack components, such as height of snow (HS) and snow water equivalent (SWE) are evaluated with independent pointwise in-situ measurements and spatially distributed satellite images. The snow model results show an average success of 0.81 and 0.66 in terms of Nash-Sutcliffe Efficiency (NSE) for the calibration and validation periods, respectively. In addition, the extreme snowfall and early snowmelt event that occurred in 2004 snow season is further evaluated by the snow model and satellite products.

How to cite: Sorman, A. A. and Ertas, M. C.: Assessment of Distributed Snow Modeling using Ground and Remote Sensing Data in Mountainous Eastern Turkey, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12877, https://doi.org/10.5194/egusphere-egu2020-12877, 2020.

Spatial extent of snow has been declared as an essential climate variable. Accurate modeling of snow cover is crucial for the better prediction of snow water equivalent and, consequently, for the success of general circulation and weather forecasting models as well as climate change and hydrological studies. This presentation mainly focuses on the representation of the latest findings of our efforts in fractional snow cover mapping on MODIS images by data-driven machine learning methodologies. For this purpose, a dataset composed of 20 MODIS - Landsat 8 image pairs acquired between Apr 2013 and Dec 2016 over European Alps were employed. Artificial neural networks (ANN), multivariate adaptive regression splines (MARS), support vector regression (SVR) and random forest (RF) models were trained and tested by using reference FSC maps generated from higher spatial resolution Landsat 8 binary snow maps. ANN, MARS, SVR and RF models exhibited quite good performance with average R ≈ 0.93, whereas the agreement between the reference FSC maps and the MODIS’ own product MOD10A1 (C5) was slightly poorer with R ≈ 0.88.

How to cite: Kuter, S. and Akyurek, Z.: Latest Advances in Fractional Snow Cover Mapping on MODIS Data by Machine Learning Algorithms, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13193, https://doi.org/10.5194/egusphere-egu2020-13193, 2020.

EGU2020-13945 | Displays | GI4.6

Designing and launching a citizen initiative to monitor snow depth in Sierra Nevada (South Spain)

David Pulido-Velazquez, Antonio-Juan Collados-Lara, Eulogio Pardo-Igúzquiza, Pedro Ossorio, Leticia Baena-Ruiz, Juan Ignacio Lopez-Moreno, Crisanto Martín-Montañés, Antonio Navarro, and Rosa Maria Mateos

The spatial distribution of snow thickness in extensive alpine regions can be estimated with high spatial resolution from LIDAR data capture. However, due to the significant economic cost of these activities, its application is limited, especially to cover large areas. Traditionally, snow thickness has been estimated by applying interpolation methods and/or hydrological models that approximate the distribution of snow from fieldwork data. In some places there is permanent infrastructure that facilitates the collection of data. In Spain, within the framework of the national snow depth monitoring program (ERHIN, initiated in 1981), an infrastructure consisting of a network of poles distributed over various mountain ranges was generated to obtain measurements by direct observation from helicopter flights (1-3 per year). This monitoring activity has been drastically reduced and even cancelled in some mountain ranges in recent years as a result of budget cuts. In order to maintain the observation of snow, we propose a novel approach to involve groups of volunteers to take advantage of the existing (or optimally increased) infrastructure that are underutilized or in disuse, to gather photos of poles as a means of monitoring snow thickness. The proposal is being applied in the Sierra Nevada (Southern Spain), and may be extended in the future across the whole Spain. The tasks performed to achieve the objective are: 1) Inventory of infrastructures and potential volunteer: The 23 poles installed by the ERHIN program in Sierra Nevada are being marked to facilitate their identification in photos sent in by volunteers. An inventory of potential volunteer and user groups has been compiled; 2) Optimum design of snowpole network for monitoring snow depth: The aim is to identify the optimal location of new poles in order to minimize uncertainty in estimates of snow depth. To solve this problem, we have employed a regression model that estimates the spatial distribution of snow depth and its uncertainty 3) Generation of tools to supply and display information: Mobile application and web platform. For the success of the activity, we need user-friendly applications that include relevant local information (e.g., location of the poles) and an adequate link to the project web for supplying and storing information; 4) Maximization of participation. Program of incentives. We have involved key institutions, such as Sierra Nevada Natural Park and Andalusian Mountaineering Federation (FAM), which predict a high participation rate by its members. To encourage collaboration, participation by volunteers will be published, including ranking and honorary awards to the most active. As stated by the Andalusian Federation of Mountaineers, this ‘competition’ will be an additional incentive to increase participation by mountaineers. The task will have a significant impact with a low economic cost; 5) Dissemination and communication of relevant: It includes the design and distribution of posters and brochures to the main potential groups of volunteers.

This research has been partially supported by the SIGLO-AN project (RTI2018-101397-B-I00) from the Spanish Ministry of Science, Innovation and Universities (Programa Estatal de I+D+I orientada a los Retos de la Sociedad).

How to cite: Pulido-Velazquez, D., Collados-Lara, A.-J., Pardo-Igúzquiza, E., Ossorio, P., Baena-Ruiz, L., Lopez-Moreno, J. I., Martín-Montañés, C., Navarro, A., and Mateos, R. M.: Designing and launching a citizen initiative to monitor snow depth in Sierra Nevada (South Spain), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13945, https://doi.org/10.5194/egusphere-egu2020-13945, 2020.

EGU2020-14123 | Displays | GI4.6

Development of Long-Term Satellite-Based Snow Mass Records in the ESA Snow CCI Project

Kari Luojus, Matias Takala, Jouni Pulliainen, Juha Lemmetyinen, Mikko Moisander, Pinja Venäläinen, Chris Derksen, Colleen Mortimer, Thomas Nagler, and Gabriele Schwaizer

Reliable information on snow cover across the Northern Hemisphere and Arctic and sub-Arctic regions is needed for climate monitoring, for understanding the Arctic climate system, and for the evaluation of the role of snow cover and its feedback in climate models. In addition to being of significant interest for climatological investigations, reliable information on snow cover is of high value for the purpose of hydrological forecasting and numerical weather prediction. Terrestrial snow covers up to 50 million km² of the Northern Hemisphere in winter and is characterized by high spatial and temporal variability making satellite observations the only means for providing timely and complete observations of the global snow cover. The ESA Snow CCI project was initiated in 2018 to improve methodologies for snow cover extent (SE) and snow water equivalent (SWE) retrieval [1] using satellite data and construct long term data records of terrestrial snow cover for climate research purposes.

The first new long term SWE data record from the ESA Snow CCI project, spanning 1979 to 2018 has been constructed and assessed in terms of retrieval performance, homogeneity and temporal stability. The initial results show that the new SWE dataset is more robust, more accurate and more consistent over the 40-year time series, compared to the earlier ESA GlobSnow SWE v1.0 and v2.0 data records [1].

The improved SWE retrieval methodology incorporates a new emission model (within the retrieval scheme), an improved synoptic weather station snow depth data record (applied to support SWE retrieval), extension of the SWE retrieval to cover the whole Northern Hemisphere.

The new Snow CCI SWE data record has been used to assess changes in the long term hemispherical snow conditions and climatological trends in Northern Hemisphere, Eurasia and North America. The general finding is that the peak hemispherical snow mass during the satellite era has not yet decreased significantly but has remained relatively stable, with changes to lower and higher SWE conditions in different geographical regions.

 

References:

[1] Takala, M, K. Luojus, J. Pulliainen, C. Derksen, J. Lemmetyinen, J.-P. Kärnä, J. Koskinen, B. Bojkov. 2011. Estimating northern hemisphere snow water equivalent for climate research through assimilation of space-borne radiometer data and ground-based measurements. Remote Sensing of Environment, 115, 12, 3517-3529, doi:10.1016/j.rse.2011.08.014.

How to cite: Luojus, K., Takala, M., Pulliainen, J., Lemmetyinen, J., Moisander, M., Venäläinen, P., Derksen, C., Mortimer, C., Nagler, T., and Schwaizer, G.: Development of Long-Term Satellite-Based Snow Mass Records in the ESA Snow CCI Project, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14123, https://doi.org/10.5194/egusphere-egu2020-14123, 2020.

EGU2020-14969 | Displays | GI4.6

Retrieving, validating, and assimilating fractional snow-covered area from emerging optical satellites for snow reanalysis

Kristoffer Aalstad, Sebastian Westermann, Joel Fiddes, James McCreight, and Laurent Bertino

Accurately estimating the snow water equivalent (SWE) that is stored in the worlds mountains remains a challenging and important unsolved problem. The SWE reconstruction approach, where the remotely sensed seasonal depletion of fractional snow-covered area (fSCA) is used with a snow model to build up the snowpack in reverse, has been used for decades to help tackle this problem retrospectively. Despite some success, this deterministic approach ignores uncertainties in the snow model, the meteorological forcing, and the remotely sensed fSCA. A trade-off has also existed between the desired temporal and spatial resolution of the satellite-retrieved fSCA depletion. Recently, ensemble-based data assimilation techniques that can account for the uncertainties inherent in the reconstruction exercise have allowed for probabilistic snow reanalyses. In addition, new higher resolution optical satellite constellations such as Sentinel-2 and the PlanetScope cubesats have been launched into polar orbit, potentially eliminating the aforementioned trade-off.

We combine these two developments, namely ensemble-based data assimilation and the emerging remotely sensed data streams, to see if snow reanalyses can be improved at the hillslope (100 m) scale in complex terrain. As a first step, we develop accurate high-resolution binary snow-cover maps using a terrestrial automatic camera system installed on a mountaintop near Ny-Ålesund (Svalbard, Norway). These maps are used to validate fSCA retrieved from various satellite sensors (MODIS, Sentinel-2 MSI, and Landsat 8 OLI) using algorithms ranging from simple thresholding of the normalized difference snow index to spectral unmixing. Through the validation, we demonstrate that the spectral unmixing technique can obtain unbiased fSCA retrievals at the hillslope scale. Next, we move to the Mammoth Lakes basin in the Californian Sierra Nevada, USA, where we have access to independent validation data retrieved from several Airborne Snow Observatory (ASO) and Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) flights. Using these airborne retrievals as a reference, we show that fSCA can be retrieved at the hillslope scale with reasonable accuracy at an unprecedented near daily revisit period using a combination of the Landsat, Sentinel-2 MSI, RapidEye, and PlanetScope satellite constellations. In a series of data assimilation experiments we show how the combination of these constellations can lead to significant improvements in hillslope scale snow reanalyses as gauged by various evaluation metrics. Furthermore, it is suggested that an iterative ensemble smoother data assimilation scheme can provide more robust SWE estimates than other smoothers that have previously been proposed for snow reanalysis. We briefly conclude with thoughts as to the current impediments to conducting a global hillslope scale snow reanalysis and propose avenues for further research, such as how snow reanalyses can help in the prediction exercise.

How to cite: Aalstad, K., Westermann, S., Fiddes, J., McCreight, J., and Bertino, L.: Retrieving, validating, and assimilating fractional snow-covered area from emerging optical satellites for snow reanalysis, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14969, https://doi.org/10.5194/egusphere-egu2020-14969, 2020.

Modeling streamflows is challenging in snow dominated high altitude regions due to limited observations, harsh topographic conditions and complex snow physics. Different uncertainties arise from multiple sources in modeling and forecasting. The uncertainties of the initial conditions are mainly tackled with data assimilation techniques. On the other hand, the uncertainty of the model structure should also be considered since assimilation techniques can only use same model and parameter sets in each implementation. Generally, this uncertainty can be taken into account using multi-modelling methods that can produce ensemble set of parameters. In order to make use of this approach, this study aims the realization of a novel method that generates a probabilistic estimate of initial states using a multi-parametric modelling method with deterministic Variational Data Assimilation, as referred to the multi-parametric variational data assimilation, MP-VarDA.  The study is accomplished for runoff predictions over the mountainous Eastern part of Turkey concerning the importance of snowmelt and the limited availability of observed data. The model pool is generated with Generalized Likelihood Uncertainty Estimation (GLUE) method with a calibrated hydrological model using HBV. The implementation of MP-VarDA assimilates both discharge and satellite snow observations on snow cover. The preliminary results having 3 model instances are promising to set a model pool for MP-VarDA method which can reduce model uncertainty. The model is also tested via hindcast experiments under close-loop mode in order to assimilate discharge and satellite snow data, and model results showed that runoff and snow state predictions are improved compared to conditional assimilation techniques.

How to cite: Sensoy, A., Uysal, G., and Alvarado Montero, R.: Multi-parametric Variational Data Assimilation of MODIS snow cover data through HBV Model in Mountainous Upper Euphrates River Catchment , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17823, https://doi.org/10.5194/egusphere-egu2020-17823, 2020.

EGU2020-18844 | Displays | GI4.6

Frozen Surface Classification Scheme for ATMS and GMI

Daniele Casella, Andrea Camplani, Paolo Sanò, Giulia Panegrossi, and Mark Kulie

Within the development of passive microwave precipitation retrieval techniques, and, in
particular, of snowfall detection and retrieval techniques, the possibility to characterize the
frozen background surface (snowcover and sea ice conditions) at the time of the overpass
appears to be a relevant task. As demonstrated by many recent studies (e.g., Tabkiri et al.,
2019, Ebtehaj and Kummerow 2017, Panegrossi et al., 2017), the microwave signal
related to snowfall is strongly influenced by the surface conditions, and the response of the
observed brightness temperatures to the presence and intensity of snowfall depends on
complex interconnections between environmental conditions (surface temperature, water
vapor content, snow water path, cloud depth, presence of supercooled droplets) and the
different surface conditions (wet or dry snow cover, sea ice concentration and type, etc.).
The use of surface classification climatological datasets results inadequate for the purpose
because of the extreme variability of the frozen surface conditions. It is therefore
necessary to be able to identify the background surface condition as close as possible (in
space and time) to that of the observation. The conically scanning GPM Microwave Imager
(GMI) and cross-track the Advanced Technology Microwave Sounder (ATMS) are the most
advanced currently available microwave radiometers. They are both equipped with
channels at several different frequencies that can be exploited both for the identification of
the frozen surface conditions and for snowfall detection and retrieval at the time of the
overpass over a precipitation event (i.e., Rysman et al., 2018). Moreover, they can be
used to analyze the potentials of future radiometers with similar characteristics such as the
EPS-SG Microwave Sounder (MWS) and Microwave Imager (MWI), which represent the
future in terms of European operational radiometers that can be exploited for precipitation
retrieval at all latitudes (including the Polar Regions). In the last years we have developed
two frozen surface classification schemes based on the use of GMI and ATMS low
frequency channels (from 10 GHz up to 36 GHz) and on ancillary near-surface
temperature and columnar water vapor data (obtained from ECMWF global ERA5
reanalysis). The algorithm is able to identify 9 classes of soil including different type of
snow and sea ice. The results of such classification have been compared with other
products, such as the NASA-GPROF soil type classification, and with snowcover and sea
ice global datasets (such as GMASI- Autosnow, and SNODAS from NOAA, and ECMWF
ERA5). In particular, the comparison with SNODAS over Northern America region shows
that the probability of detection of snow-covered surfaces varies between 86% - 98%
(79%-95%) for GMI (ATMS) with a relatively small false alarm ratio (10%-30%). The
analysis evidenced the main factors limiting the detection capability, such as the moisture
content, the presence of orography, the snow cover beam filling and the snow depth.

How to cite: Casella, D., Camplani, A., Sanò, P., Panegrossi, G., and Kulie, M.: Frozen Surface Classification Scheme for ATMS and GMI, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18844, https://doi.org/10.5194/egusphere-egu2020-18844, 2020.

Snow avalanche hazard in the Czech Republic is mainly constrained to Krkonoše mountains. Approximately twenty snow avalanches release every year during winter season, usually lasting from November to May. Although Krkonoše belongs to mid-mountain range (highest peak 1602 m a.s.l.) due to its prevailing influence of moist, cold air masses and mean annual temperature about 0 °C climate conditions are similar to high-elevation or subpolar climate. Despite the low altitude, Krkonoše experiences considerable avalanche activity at fifty-five permanent paths and even cause fatalities. The monitoring of avalanche releases has been conducted since 1961, therefore most of the avalanches were reported to the extensive database (> 1100 events). The land use of the mountain range is changing and many areas are being deforested resulting in new avalanche prone areas. The presented research is based on results of previous project focused on the avalanche hazard assessment in the Krkonoše mountains and thus results are extended, and monitoring methods and creation of avalanche susceptibility maps are improved.

It is clear, from abovementioned, that existing avalanche hazard maps have to be reassessed. Therefore, release zones and avalanche susceptibility map must be determined.

Mapping of avalanche activity includes continous monitoring of the avalanche paths by unmanned aerial systems photogrammetry (UAS-P) and ground GPS measurements of the avalanche path. This data will be used for evaluation of the mass movement dynamic model (RAMMS).  Such a monitoring covers:

The result of RAMMS model for entire Krkonoše mountain range including czech and polish side will be parametrised and compared to newly obtained data of avalanche releases. The results can be then used by public authorities such as: Krkonoše National Park administrations, Mountain rescue service of the Czech Republic or Institute of Forest Management.

 

How to cite: Souckova, M. and Juras, R.: Mapping snow avalanche releases by unmanned aerial vehicles (UAV) in Krkonoše mountain range, the Czech Republic, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19307, https://doi.org/10.5194/egusphere-egu2020-19307, 2020.

EGU2020-22347 | Displays | GI4.6

Near real time monitoring of snow cover using webcam imagery

Cemal Melih Tanis, Ali Nadir Arslan, and Miina Rautiainen

Environmental camera networks are growing in usage in different parts of the globe. Time series of webcam imagery from the camera networks are used in estimating snow cover properties. Fractional snow cover (FSC) and snow depth (SD) are two important parameters which can be estimated from the webcam imagery using image processing algorithms. Monitoring of snow cover from webcam imagery has the potential to be used in gap filling and validation of satellite derived products. It can also be used as a data source for snow monitoring in remote areas where manual measurements and in-situ sensor installation and maintenance are costly, especially under forest canopy which retrieval of signal from ground by satellites is a challenge. In this paper, we have used multiple webcams from MONIMET Camera Network in Finland and Finnish Meteorological Institute Image Processing Toolbox (FMIPROT) on the cloud to establish an automated processing chain which reports FSC and SD estimations in near real time, available in FMIPROT website. Image processing algorithms are implemented in the toolbox, the images from last year are also processed and the results are compared with ultrasonic in-situ measurements and values generated by visual inspections on images. In the website, estimations from the day-time images of the latest one month are visualized on interactive plots, along with time-lapse animations of images, with a latency of 3 hours.

How to cite: Tanis, C. M., Arslan, A. N., and Rautiainen, M.: Near real time monitoring of snow cover using webcam imagery, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22347, https://doi.org/10.5194/egusphere-egu2020-22347, 2020.

EGU2020-22350 | Displays | GI4.6

The Nordic Snow Network (NordSnowNet): Arctic research and snow data from observations and models

Outi Meinander, Ali Nadir Arslan, Leena Leppanen, and Jouni Pulliainen and the NordSnowNet

Snow cover is an essential climate variable directly affecting the earth energy balance. Proper description and assimilation of snow cover information into hydrological, land surface, meteorological and climate models are critical to address the impact of snow on various phenomena, to predict local snow water resources and to warn about snow-related natural hazards. This induces a challenging problem of bridging information from micro-structural scales of the snowpack up to the grid resolution in models. 

These questions are included in the actions of the Nordic Snow Network, NordSnowNet, http://nordsnownet.fmi.fi/, a recent project launched in 2019 under the Nordic Arctic Co-operation Programme of the Nordic Council of Ministers, which is administered by Nordregio and contributes to enhancing knowledge about the Arctic region (https://nordregioprojects.org/arctic-programme/nordic-snow-network-nordsnownet/). The point of view of the network will be focused on snow in Nordic and related Arctic areas: making existing Nordic-Arctic research and snow data from observations and models (forecasts and assimilated observations by weather and hydrology models, projections by the climate models) visible for the researcher, data user and education communities. It supports snow-related research and development of applications by the exchange of information and data, arranging workshops, training and supporting also informal Nordic researcher contacts and meetings. For example, citizen observations will be collected on color snow and ice, to estimate the appearance of dirty snow due to deposition of atmospheric aerosols and algae existing on snow and ice, in co-operation with the Ministry of Foreign Affairs of Finland’s project IBA-FIN-BCDUST (2019-2020, PI Meinander FMI, https://en.ilmatieteenlaitos.fi/iba-project). The color of snow and ice has effect on the snow and ice albedo, which in turn influences snow and ice melt.

The project is managed by the Finnish Meteorological Institute (FMI) by Ali Nadir Arslan, and the steering committee with representatives from each partner country, including Finland (Outi Meinander, FMI), Denmark (Kristian Pagh Nielsen, Danish Meteorological Institute), Estonia (Marko Kaasik, University of Tartu), Greenland (Kirsty Langley, Asiaq Greenland), Iceland (Pavla Dagsson-Waldhauserova, Agricultural Institute of Iceland), Sweden (Patrick Samuelsson, Swedish Meteorological Institute), and Norway (Mariken Homleid, Norwegian Meteorological Institute). The partners are Nordic meteorological institutes and collaborative universities and research institutes. The first field work activity will be in the Arctic Space Centre in Sodankylä, Finland, in early April 2020. The network is open and welcomes collaborators to join by contacting the corresponding country representative.

We gratefully acknowledge the Nordic Council of Ministers Arctic Co-operation Programme and Nordregio for their support to the NordSnowNet.

How to cite: Meinander, O., Arslan, A. N., Leppanen, L., and Pulliainen, J. and the NordSnowNet: The Nordic Snow Network (NordSnowNet): Arctic research and snow data from observations and models , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22350, https://doi.org/10.5194/egusphere-egu2020-22350, 2020.

GI5.1 – Ground Penetrating Radar: technology, methodology, applications, and case studies

EGU2020-21972 | Displays | GI5.1

The effect of geometry on the feed impedance for a PCB-dipole antenna and the time domain radiation emission from the feed point

Frank Podd, Xianyang Gao, Wouter van Verre, David Daniels, and Anthony Peyton

The measured reflected radar waveform from an object in free space depends on many factors including the antenna’s geometry, the impedance of the balun and feed-cable, the object position in relation to the antennas, and the object’s angular scattering function. Analytical methods can be simplified when the object is a long way away from the antenna. However, for near-surface GPR applications, such as landmine detection, the objects are generally in the near-field region of the antennas. The ultra-wideband scattering function of objects can be complex even in the far-field.

To optimise GPR antenna design, it is necessary to be able to quickly estimate the Spatio-Temporal Point Spread Function (ST-PSF) for a bi-static antenna pair. Conventionally, the PSF is considered only in the far-field and in the frequencies domain at spot-frequencies. This paper outlines the steps needed to create an analytical approximation of the ST-PSF, and it describes the first step in this process - the parametric modelling of the antenna geometry on feed impedance. The described analysis uses the case of a PCB dipole for both the excitation and the receive antennas as an example of the approach.

The results show the importance of understanding the antenna feed impedance for both the compactness of the radiated pulse and the transfer function of the receive antenna. The paper discusses the optimum cable impedance, assuming a balanced source, and consequentially, the optimum case for matching to heavily damped antenna designs. This paper covers the first step to an analytical approximate of more commonly used (non-damped) dipole antennas.

How to cite: Podd, F., Gao, X., van Verre, W., Daniels, D., and Peyton, A.: The effect of geometry on the feed impedance for a PCB-dipole antenna and the time domain radiation emission from the feed point, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21972, https://doi.org/10.5194/egusphere-egu2020-21972, 2020.

EGU2020-10632 | Displays | GI5.1

Application of an advanced algorithm for automated hyperbola detection, including Canny edge detector, to GPR data from IFSTTAR test field

Željko Bugarinović, Lara Pajewski, Aleksandar Ristić, Milan Vrtunski, and Miro Govedarica

Automated processing and extraction of useful information from GPR data is a complicated task, for which various approaches have been developed during the last years. This work examines the introduction of Canny edge detector as a new preliminary step of an advanced algorithm for automated hyperbola detection [1, 2]. The overall algorithm aims to identify radargram portions wherein hyperbolic reflections apices are present and extract the coordinates of such apices.

The newly introduced step utilizing Canny edge detector consists of two main procedures: (1) identification of edge pixels in a radargram and (2) elimination of edge pixels that do not meet specific criteria. The latter procedure aims to accelerate the algorithm by reducing the number of pixels, without compromising the correct detection and localization of hyperbola apices. For the elimination of unnecessary edge pixels, different criteria have been designed and tested; a practical solution has been found, which yields the elimination of the highest number of unnecessary edge pixels without eliminating useful edge pixels. No pixels are eliminated from the close vicinity of hyperbola apices since it is better to keep a higher number of edge pixels than to eliminate useful ones. In the implementation of the algorithm, special attention has been paid to its execution time, thinking of real-time applications.

The upgraded algorithm was tested on experimental radargrams from IFSTTAR (The French Institute of Science and Technology for Transport, Development, and Networks) test field in Nantes, France [3]. That test field consists of vertical sections filled with different materials and hosting many buried objects, such as cables and pipes, or walls and stones, imitating common scenarios in urban areas. Radargram acquisition was done using antennas with different central frequencies. Radargrams containing hyperbolic reflections were selected and used for testing the upgraded algorithm, with promising results.

References

[1] A. Ristić, Ž. Bugarinović, M. Govedarica, L. Pajewski, and X. Derobert, “Verification of algorithm for point extraction from hyperbolic reflections in GPR data,” Proc. 9th International Workshop on Advanced Ground Penetrating Radar (IWAGPR 2017), Edinburgh, UK, pp. 1-5, 2017.

[2] A. Ristić, M. Vrtunski, M. Govedarica, L. Pajewski, and X. Derobert, “Automated data extraction from synthetic and real radargrams of district heating pipelines,” Proc. 9th International Workshop on Advanced Ground Penetrating Radar (IWAGPR 2017), Edinburgh, UK, pp. 1-5, 2017.

[3] X. Dérobert and L. Pajewski, “TU1208 Open Database of Radargrams: The Dataset of the IFSTTAR Geophysical Test Site,” Remote Sensing, Vol. 10(4), 530, pp. 1-50, 2018.

How to cite: Bugarinović, Ž., Pajewski, L., Ristić, A., Vrtunski, M., and Govedarica, M.: Application of an advanced algorithm for automated hyperbola detection, including Canny edge detector, to GPR data from IFSTTAR test field, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10632, https://doi.org/10.5194/egusphere-egu2020-10632, 2020.

Over the years, the detection and imaging of targets embedded in layered media has become of paramount importance in a diverse set of problems including those in microwave remote sensing, nondestructive testing, ground penetrating radar (GPR), and through-the-wall imaging (TWRI). Specifically, development of imaging techniques for visually inaccessible targets buried under the ground has attracted growing interest in archaeology, underground weapon detection, building safety and durability assessment, geophysical exploration, etc. For high resolution imaging in these applications, usually a long aperture is synthesized using an ultra-wideband transmitted signal; this makes the approach impractical and/or costly in many realistic situations. To reduce the collected data volume in order to accelerate radar data acquisition and processing times such that prompt actionable intelligence would be possible, several research groups in recent years have applied Compressive Sensing (CS) to radar imaging in GPR to reconstruct a sparse target scene from far fewer non-adaptive measurements. The standard CS techniques, however, are mainly based on L1-norm minimization, which is primarily effective in detecting the presence of targets as it cannot accurately reconstruct the target shape and/or differentiate closely spaced targets from an extended target.

In this presentation, we give an overview of our group’s recent works on image reconstruction for both SAR-based and multiple-input multiple-output (MIMO) based GPR targets in a multilayered subsurface medium using CS. In our approach, the subsurface layers are accurately and efficiently accounted for in the sparse-image reconstruction through analytically derived expressions for the Green’s functions of multi-layered lossy dielectric media. In particular, we will discuss the use of total variation minimization (TVM) and its advantages over the L1-norm minimization which is often used in the standard radar implementation of CS. The TVM technique minimizes the gradient of the image instead of the image itself, and as a result leads to better shape reconstruction of large and/or multiple subsurface targets. In addition, we also discuss the use of group sparsity reconstruction (GPS) technique and compare its performance with that of TVM under various noise levels. Numerical results for sparse imaging in various subsurface scenarios using different reduced sets of SAR and MIMO radar transmit and receive antenna elements as well as reduced number of frequency bins will be given in the presentation.

How to cite: Hoorfar, A.: Advances in Sparse Image Reconstruction of GPR Subsurface Targets, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4231, https://doi.org/10.5194/egusphere-egu2020-4231, 2020.

EGU2020-1887 * | Displays | GI5.1 | Highlight

Mapping Subsurface Drainage in Agricultural Areas Using a Frequency-Domain Ground Penetrating Radar

Triven Koganti, Ellen Van De Vijver, Barry J. Allred, Mogens H. Greve, Jørgen Ringgaard, and Bo V. Iversen

Artificial subsurface drainage systems are installed in agricultural areas to remove excess water and convert poorly naturally drained soils into productive cropland. Some of the most productive agricultural regions in the world are a result of subsurface drainage practices. Drain lines provide a shortened pathway for the release of nutrients and pesticides into the environment, which presents a potentially increased risk for eutrophication and contamination of surface water bodies. Knowledge of drain line locations is often lacking. This complicates the understanding of the local hydrology and solute dynamics and the consequent planning of mitigation strategies such as constructed wetlands, saturated buffers, bioreactors, and nitrate and phosphate filters. In addition, accurate knowledge of the existing subsurface drainage system is required in designing the installation of a new set of drain lines to enhance soil water removal efficiency. The traditional methods of drainage mapping involve the use of tile probes and trenching equipment which are time-consuming, tiresome, and invasive, thereby carrying an inherent risk of damaging the drain pipes. Non-invasive geophysical sensors provide a potential alternative solution to the problem. Previous research has focused on the use of time-domain ground penetrating radar (GPR) with variable success depending on local soil and hydrological conditions and the center frequency of the specific equipment used. For example, 250 MHz antennas proved to be more suitable for drain line mapping. Recent technological advancements enabled the collection of high-resolution spatially exhaustive data. In this study, we present the use of a stepped-frequency continuous wave (SFCW) 3D-GPR (GeoScope Mk IV 3D-Radar with DXG1820 antenna array) mounted in a motorized survey configuration with real-time georeferencing for subsurface drainage mapping. The 3D-GPR system offers more flexibility for application to different (sub)surface conditions due to the coverage of wide frequency bandwidth (60-3000 MHz). In addition, the wide array swathe of the antenna array (1.5 m covered by 20 measurement channels) enables effective coverage of three-dimensional (3D) space. The surveys were performed on twelve different study sites with various soil types with textures ranging from sand to clay till. While we achieved good success in finding the drainage pipes at five sites with sandy, sandy loam, loamy sand and organic topsoils, the results at the other seven sites with more clay-rich soils were less successful. The high attenuation of electromagnetic waves in highly conductive clay-rich soils, which limits the penetration depth of the 3D-GPR system, can explain our findings obtained in this research.

How to cite: Koganti, T., Van De Vijver, E., J. Allred, B., H. Greve, M., Ringgaard, J., and V. Iversen, B.: Mapping Subsurface Drainage in Agricultural Areas Using a Frequency-Domain Ground Penetrating Radar, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1887, https://doi.org/10.5194/egusphere-egu2020-1887, 2020.

EGU2020-1406 | Displays | GI5.1 | Highlight

Development of ground penetrating radar for enhanced root phenotyping and carbon sequestration

Dirk Hays, Matt Wolfe, Iliyana Dobreva, and Henry Ruiz

Currently atmospheric carbon has reached 405 ppm or 720 GtC.  As is widely known, this increasing atmospheric carbon dioxide, methane and nitrous oxide are primary contributing factors in increasing global temperatures.  Current measurements show that sources of emission such as the burning of fossil fuels contributes 9.9 GtC/yr, while land use change contributes 1.5 GtC/yr. We have identified that crops possessing a subsurface rhizome in particular, in addition to high root biomass, are essential and capable of increasing crop derived soil carbon sequestration by 10-fold.  If the presence of a high biomass rhizome were bred into the world’s major grain crops wheat, rice, maize, barley, sorghum and millets and grown worldwide in no-tillage conditions, these crops could sequester and offset current carbon emissions by 9Gt carbon on a yearly basis. We have developed a new ground penetrating radar instrument and analytical software, which will be presented, as a needed for high throughput non-destructive phenotyping, selection and speed breeding new high root biomass cultivars of the worlds major cultivated crops and forages as a key component for crop-based carbon sequestration driven climate change mitigation. 

How to cite: Hays, D., Wolfe, M., Dobreva, I., and Ruiz, H.: Development of ground penetrating radar for enhanced root phenotyping and carbon sequestration, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1406, https://doi.org/10.5194/egusphere-egu2020-1406, 2020.

EGU2020-3033 | Displays | GI5.1

Ice-contact deltas investigation using ground penetrating radar (GPR), sedimentology, electrical resistivity tomography (ERT) and , Salpausselka I and II near Lahti, Finland

Bartosz Kurjanski, Brice Rea, Matteo Spagnolo, David Cornwell, Jukka-Pekka Palmu, John Howell, Andres Quiros, and Jean-Christophe Comte

In Finland, two large “moraine” ridges (Salpausselka I and Salpausselka II), extending to over 600 km in length, delineate two major stillstand/readvance positions of the Fennoscandian ice sheet during the last deglaciation (Glückert, 1986). They are inferred to be chronologically related to the cold stage known as the Younger Dryas which occurred at the end of the last glaciation. During this time the Baltic ice lobe and the Finnish Lake District ice lobe, constituting a part of the southern margin of the Fennoscandian ice sheet, were grounded in a large proglacial lake, the Baltic ice lake, a predecessor to the modern-day Baltic Sea. The “moraine” ridge is mostly composed of glaciofluvial sands, gravels and boulders rather than diamicton and deposited on crystalline, impermeable bedrock and constitute  freshwater aquifer in southern and eastern Finland. The average thickness of ice-contact deltas sediments is estimated at between 20 and 60 meters and is highly variable.

Outcrop studies are combined with GPR and ERTprofiles to provide insight into the aquifer architecture at different scales and depths of investigation. This study aims to improve our understanding of such deposits in the subsurface, especially about their internal structure, sedimentary facies distribution and potential barriers and/or baffles to fluid flow and poro-perm characteristics.

How to cite: Kurjanski, B., Rea, B., Spagnolo, M., Cornwell, D., Palmu, J.-P., Howell, J., Quiros, A., and Comte, J.-C.: Ice-contact deltas investigation using ground penetrating radar (GPR), sedimentology, electrical resistivity tomography (ERT) and , Salpausselka I and II near Lahti, Finland, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3033, https://doi.org/10.5194/egusphere-egu2020-3033, 2020.

EGU2020-21096 * | Displays | GI5.1 | Highlight

Detecting footprints with GPR

thomas urban

Recent field research at White Sands National Park, New Mexico, USA, has used ground-penetrating radar to detect the footprints of Pleistocene humans, mammoths, and ground sloths. The technique has been succesful with a range of antenna frequencies and for detecting footprints of many different sizes. Perhaps more importantly, the method has been shown to successfully detect fooprints that are not visible to the human eye, often with sufficent detail to differntiate species. This work raises an obvious question about whether GPR could be used to detect footprints in a range of other contexts, or whether the circumstances seen at White Sands are unique. 

How to cite: urban, T.: Detecting footprints with GPR, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21096, https://doi.org/10.5194/egusphere-egu2020-21096, 2020.

Ground Penetrating Radar (GPR) systems need to be calibrated on a recurrent basis and their performance shall be periodically verified, in accordance with manufacturer recommendations and specifications. Nevertheless, most GPR owners in Europe employ their radar units and antennas for years without ever having them verified by manufacturers, unless major flaws or issues become evident. In this framework, Members of COST Action TU1208 have recently carried out a critical analysis of the few existing procedures for the calibration and performance verification of GPR systems; and, they have proposed four improved experimental tests to evaluate the signal-to-noise ratio, short-term stability, linearity in the time axis, and long-term stability of the GPR signal [1]. In this work, we present the results of the tests executed in Novi Sad, Serbia, on a GSSI SIR 3000 control unit equipped with GSSI ground-coupled antennas having central frequencies of 400 MHz and 900 MHz. We have experienced that the execution of the tests helps to attain stronger awareness about the behaviour and limits of owned GPR equipment. It is also interesting to check how the results of the tests change over time and in different environmental conditions, to analyze the performance evolution of the equipment. Main aim of this abstract is to spread the voice and encourage GPR owners and manufacturers to execute the tests. If a wide variety of control units and antennas are tested, of older and more recent conception, with different numbers of working hours, reliable thresholds for the tests can be established and the proposed procedures can be further refined and upgraded. Moreover, the results of the tests can be translated into accuracy levels of measured physical and geometrical quantities, to get some awareness about the uncertainty of results of a GPR survey (e.g., achieved accuracy levels in the estimation of layer thicknesses).

 

[1] L. Pajewski, M. Vrtunski, Ž. Bugarinović, A. Ristić, M. Govedarica, A. van der Wielen, C. Grégoire, C. Van Geem, X. Dérobert, V. Borecky, S. Serkan Artagan, S. Fontul, V. Marecos, and S. Lambot, "GPR system performance compliance according to COST Action TU1208 guidelines,"  Ground Penetrating Radar, Volume 1, Issue 2, Article ID GPR-1-2-1, July 2018, pp. 2-36, doi.org/10.26376/GPR2018007.

How to cite: Vrtunski, M., Pajewski, L., Ristić, A., Bugarinović, Ž., and Govedarica, M.: Results of experimental tests for the evaluation of the signal-to-noise ratio, short-term stability, linearity in the time axis, and long-term stability of the GPR signal - according to COST Action TU1208 guidelines, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18836, https://doi.org/10.5194/egusphere-egu2020-18836, 2020.

EGU2020-7909 | Displays | GI5.1

Recognition of horizontal layers in a segmented radargram after the application of Canny edge detector

Milan Vrtunski, Željko Bugarinović, Lara Pajewski, Aleksandar Ristić, and Miro Govedarica

This paper presents a method for the automated detection and elimination of horizontal reflections from ground penetrating radar (GPR) profiles after Canny edge filtering. Horizontal reflections are generated by interfaces between different media parallel to the air-soil interface. The recognition of horizontal layers is a crucial task when the number of layers and their thicknesses need to be estimated (e.g., in GPR road surveys). Identifying and deleting horizontal reflections from a radargram is also useful to facilitate the subsequent automated extraction of hyperbolic reflections [1-3]. It has to be noted that the removal of horizontal layers can increase the level of radargram segmentation.

In the proposed method, the first segmentation step is the application of Canny edge detector to the entire radargram. Then, horizontal layer recognition is done by carefully choosing boundary values. These values are varied many times until optimal values, depending on data acquisition parameters, are adopted. Special attention is paid to time efficiency of both segmentation steps, to investigate the possibility of employing the proposed solution in near real-time applications. The final result is an image where edge pixels arranged horizontally are removed.

Testing of this algorithm is done in MATLAB software environment, on a set of data with different levels of complexity, by varying the acquisition parameters.

 

References

[1]  A. Ristić, Ž. Bugarinović, M. Govedarica, L. Pajewski, and X. Derobert, “Verification of algorithm for point extraction from hyperbolic reflections in GPR data,” Proc. 9th International Workshop on Advanced Ground Penetrating Radar (IWAGPR 2017), Edinburgh, UK, pp. 1-5, 2017.

[2]  A. Ristić, M. Vrtunski, M. Govedarica, L. Pajewski, and X. Derobert, “Automated data extraction from synthetic and real radargrams of district heating pipelines,” Proc. 9th International Workshop on Advanced Ground Penetrating Radar (IWAGPR 2017), Edinburgh, UK, pp. 1-5, 2017.

[3]  Ž. Bugarinović, S.  Meschino, M. Vrtunski, L. Pajewski, A. Ristić, X. Derobert, and M. Govedarica, “Automated Data Extraction from Synthetic and Real Radargrams of Complex Structures,” Journal of Environmental and Engineering Geophysics, Vol. 23(4), pp. 407-421, 2018.

How to cite: Vrtunski, M., Bugarinović, Ž., Pajewski, L., Ristić, A., and Govedarica, M.: Recognition of horizontal layers in a segmented radargram after the application of Canny edge detector, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7909, https://doi.org/10.5194/egusphere-egu2020-7909, 2020.

EGU2020-22361 | Displays | GI5.1

Full-waveform inversion of Ground Penetrating Radar data for target characterization in multilayer environments

Alessandro Fedeli, Matteo Pastorino, and Andrea Randazzo

In the last decades, ever growing efforts have been devoted to the development of techniques for extracting information from Ground Penetrating Radar (GPR) measurements. In particular, the processed data are used to retrieve two different kinds of features. The first kind includes the so-called qualitative properties of buried targets, which are typically related to the location and/or the shape of the objects. The second kind of features is related to the quantitative dielectric characterization of the underground targets. Both strengths and weaknesses of qualitative and quantitative approaches are well known in the scientific community. Despite the more complex mathematical structure of quantitative techniques, their use is attracting an increasing attention in multiple geophysical and engineering applications.

In this contribution, the full dielectric characterization of the region of interest is retrieved by a quantitative inversion approach that works in the mathematical framework of Lebesgue spaces with variable exponents. The most important parameter of this algorithm is represented by the map of the exponent function inside the investigation domain. Here, different strategies for obtaining and refining this map in an adaptive fashion iteration-by-iteration are proposed. Numerical results are presented to check the effectiveness of the inversion approach.

How to cite: Fedeli, A., Pastorino, M., and Randazzo, A.: Full-waveform inversion of Ground Penetrating Radar data for target characterization in multilayer environments, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22361, https://doi.org/10.5194/egusphere-egu2020-22361, 2020.

EGU2020-22503 | Displays | GI5.1

Performance analysis of Two-class SVM to detect thin interlayer debondings within pavement structures

Shreedhar Savant Todkar, Vincent Baltazart, Amine Ihamouten, Xavier Dérobert, and Jean-Michel Simonin

In the field of pavement monitoring, Ground Penetrating Radar (GPR) methods are gaining prominence due to their ability to perform non-destructive testing of the subsurface. In this context, the detection and characterization of subsurface debondings at an early stage is recommended to avoid further degradation and to maintain the lifespan of these structures. To mitigate the limited time resolution of the conventional GPR devices, this paper develops the detection of thin debonding (of millimeter-order) by monitoring small changes in the time domain GPR data by specific data processing techniques (with certain automatic capabilities).

In this paper, we propose to use the supervised machine learning method, namely Two-class Support Vector Machines (SVM) to achieve the objectives. In addition, by means of time domain GPR signal features, we aim at reducing the computational burden and also increase the efficiency of SVM. The method is implemented to process independent 1D GPR A-scan data.

Furthermore, the performance assessment of Two-class SVM is carried out on both simulated and field data by means of Sensitivity Analysis to identify the parameters that affect its performance. While simulated data is generated using the analytic Fresnel data model, the field data are UWB Stepped-Frequency GPR (SF-GPR) data which were collected over artificially embedded debondings. The data was acquired during the Accelerated Pavement Tests (APTs) conducted at the IFSTTAR's fatigue carousel to survey debonding growth in the defect-affected zones at various stages of fatigue.

Two-class SVM presented the ability to detect thin millimetric debondings. Whereas, sensitivity analysis demonstrated a quick and efficient way to assess the pavement conditions.

How to cite: Todkar, S. S., Baltazart, V., Ihamouten, A., Dérobert, X., and Simonin, J.-M.: Performance analysis of Two-class SVM to detect thin interlayer debondings within pavement structures, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22503, https://doi.org/10.5194/egusphere-egu2020-22503, 2020.

EGU2020-7797 * | Displays | GI5.1 | Highlight

Application of GPR in assessing of concrete dam structures health

Aleksandar Ristic, Željko Bugarinović, Milan Vrtunski, Miro Govedarica, and Lara Pajewski

In this paper an application of GPR in the analysis of concrete structure is presented. Scanning is done as a part of preparation for mitigation works of dam ’Grančarevo’. The goal was to inspect existing small cracks and leakages. The dam is arc-shaped concrete dam with double curvatures. It is operational since 1968, and is situated 18km downstream from the wellspring of Trebišnjica river and 17km upstream from the town Trebinje, in Bosnia and Herzegovina. Relative height of the dam is 123m, while its width along the crown is 439m. Continuous monitoring of dam’s construction and surrounding terrain is conducted at over 800 measuring points. In order to determine precise position, geometry and propagation of cracks, this was the first time GPR was used.

GPR scanning was done on several important locations: on the crown, downstream face, internal galleries, down- and upstream walls, using antennas with 900 and 400MHz central frequencies. Based on scanning results, position and geometry of cracks within the concrete are successfully determined. Lateral scanning (on downstream face of the dam) are correlated with the results obtained on the crown. Also, at several locations, zones with higher humidity are noticed. These zones are significant since they present areas of higher priority during mitigation and they are often found in the vicinity of junctions between two concrete segments of the dam.

Obtained results indicate that GPR technology is rather useful tool for structure health monitoring which provides information that are significant in planning mitigation measures and extending a lifetime of a concrete object.

 

How to cite: Ristic, A., Bugarinović, Ž., Vrtunski, M., Govedarica, M., and Pajewski, L.: Application of GPR in assessing of concrete dam structures health, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7797, https://doi.org/10.5194/egusphere-egu2020-7797, 2020.

EGU2020-8900 | Displays | GI5.1

Alternative solution to the gamma bench for the dielectric characterization of materials

Imen boughanmi, Cyrille Fauchard, Nabil Benjelloun, and Zouheir Riah

In the field of civil engineering, and more particularly in the road building, it is necessary to control some physical parameters with standard methods. These controls ensure the implementation is performed according to the technical specifications. They also allow to optimize the structure dimensions  with the best safety/cost ratio and an optimal lifetime. Compactness related to density and therefore indicative of mechanical strength necessary to support traffic solicitations is a key parameter to control. Currently, density control in the laboratory is done using bench with nuclear sources on pavement cores, based on the emission and reception of gamma rays. Its replacement has now become a major issue since this method generates increasingly high costs and constraints (use, storage, transport and exposure to ionizing radiation). The objective of this work is to find an alternative non-nuclear solution to control the pavement compactness with an accuracy equivalent to the gamma-bench method . The proposed solution is an electromagnetic bench (EM), allowing cores tomography to measure permittivity. The density will then be evaluated by means of mixing rules. The EM bench consists of a vector network analyzer (Agilent E8362B) and two Ultra-Wide Band antennas [1.4-15 GHz] which are developed in this project in order to have the best performances (accuracy, dimensions…).

The antennas are placed facing each other, separated by a distance D.  A cylindrical sample (core) extracted from stratified road medium of diameter d to be tested is placed in the middle of the system and both antennas move with a given step (ranging from a few mm to 1 cm) along the sample to measure by stratification the core EM properties. The entire EM bench is motorized and driven by software developed in the laboratory. At each step, a measurement of S21 -parameter is recorded. Then signals are processed in the time domain to evaluate the relative permittivity.

The first results of modeling and measurements on laboratory asphalt samples show that the system makes it possible to evaluate the relative permittivity of different stratified materials. Accuracy, resolution and perspectives will be discussed.

key words : density, asphalt concrete, radar, electromagnetic bench

How to cite: boughanmi, I., Fauchard, C., Benjelloun, N., and Riah, Z.: Alternative solution to the gamma bench for the dielectric characterization of materials, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8900, https://doi.org/10.5194/egusphere-egu2020-8900, 2020.

EGU2020-3031 * | Displays | GI5.1 | Highlight

Magnetometric and ground penetrating radar investigations in the Aegyssus archaeologic site

Sorin Anghel, Andrei Gabriel Dragos, Gabriel Iordache, and Ioan Cornel Pop

The Aegyssus archaeological site is located on the Monument Hill in the North-Eastern section of Tulcea, the fortress was built at the end of the 4th century B.C. Its name, of Celtic origin, derived from a legendary founder, Caspios Aegyssos. At the beginning of 2nd century, the town was included in the Danubian limes (boundary). Then, starting with the 3rd century, it became an important military headquarters. The 6th century finds it as an episcopal residence. Urban life knows an end in the first quarter of the 7th century and a revival in the 10th and 11th centuries.

The geophysical investigation has been performed by means of the integrated use of three different high resolution and non invasive geophysical techniques: magnetic mapping, ground penetrating radar profiling (GPR) and magnetic susceptibility measurements.

Magnetic and ground penetrating radar methods are widely used for archaeological prospecting as very effective methods able to detect buried structures at small depths. These methods were applied for the investigation of two perimeters within the site of the ancient city of Aegyssus, an ancient Roman fortress from North Dobrudja, Romania, which was built in the first century. The primary objective was to determine the extension in the underground of a partially excavated wall. The maximum magnetic anomalies revealed the possible location of the buried wall.

The magnetometric investigation has been carried out using a protonic magnetometer G-856 GEOMETRICS in gradiometric mode, with the two magnetic sensors set in a vertical direction separated by a distance of 1 m.

A total of 20 ground penetrating radar profiles were acquired with 250 MHz antenna aiming in identifying geological and archaeological anomalies in order to assist archaeologists in an excavation program.

The GPR results indicated clear geophysical anomalies characterized by hyperbolic reflections. These anomalies were confirmed by the excavation of test units, allowing the identification anthropogenic features such as a fire-hearth structure and wooden artifact, and natural features.

The results showed the efficiency of GPR and magnetometric methods in identifying potential buried archaeological targets, and they are oriented towards reducing costs and increasing the probability of finding archaeological targets.

Our geophysical results helped to define spatial pattern of the buried remains, to define the geometry of the anthropogenic settlements and to obtain detailed information about the composition and the manufacturing processes of different building materials.

This work was supported by Romanian Ministry of Research and Innovation through the Project “Fluvimar” (Program 1. Development of the National Research-Development System. Subprogram 1.2. Institutional Performance) and Core Programme PN 19 20 05 01. 

How to cite: Anghel, S., Dragos, A. G., Iordache, G., and Pop, I. C.: Magnetometric and ground penetrating radar investigations in the Aegyssus archaeologic site, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3031, https://doi.org/10.5194/egusphere-egu2020-3031, 2020.

EGU2020-5310 | Displays | GI5.1 | Highlight

Geophysical investigation using the GPR method: a case study of a lead contamination in Santo Amaro, Bahia, Brazil

Alexandre Lago, Iago Costa, and Fernanda Cunha

The town of Santo Amaro, in the state of Bahia, Brazil, presents a history of contamination, mainly of lead (Pb) originating from the intense activity of metallurgical extraction by the mining company “Plumbum-Mineração e Metalurgia Ltda.” between the years of 1956 and 1993. Over this period, the lead slag was deposited carelessly in the factory area, creating a huge hazardous waste site. Subsequently, the problem increased when this slag was used as the basis for the paving of city streets, gardens, and school yards due to its granular characteristic and good support capacity. However, the ongoing need to remove the street paving for work on the water and sewage networks requires the exposure of the slag, making it a source of active contamination. In this context, the Ground Penetrating Radar (GPR) method was used as a tool to support and guide the evaluation of the existence of anomalous areas associated with the source of local contamination (slag) under the paving. In this work the data was acquired by moving the GPR using the of constant offset technique and a sampling interval of 5 cm between the traces. The shoots and trace records were registered continuously with the use of a calibrated wheel. The results obtained by this study show the potential of applying the GPR method to the environmental characterization of the subsoil of paved streets, making it possible to identify the resistive material contaminants (lead slag) as well as the various layers: paving, soil-slag, and massapê soil. These layers are characterized by distinct reflection patterns. The first observed reflection pattern has high amplitude with horizontal and continuous reflectors, which correspond to a characteristic pattern of urban street paving. The second reflection pattern is characterized by reflectors with amplitude variations (horizontal and inclined, continuous and discontinuous), which indicate the heterogeneity of the medium and corresponds to the soil pattern mixed with the resistive slag material. The third reflection pattern is characterized by low amplitude with chaotic and totally discontinuous reflectors, and occurs just below the second reflection pattern. This pattern of reflection marks the region in which the electromagnetic GPR signal is absorbed by the medium. This absorption is an effect of the attenuation of the electromagnetic signal by the presence of electrically conductive layers of the characteristic massapê soil (clayey to very clayey) of the study area. GPR data also enabled the identification of reflectors associated with anthropogenic interferences (manholes, train lines, pipelines, etc.). Borehole samples confirmed the existence of the contaminant (lead slag). Anomalous concentrations of heavy metals, mainly lead, were observed in the locations indicated by geophysical results using the GPR method, showing the importance of the use of geophysics in environmental characterization programs.

How to cite: Lago, A., Costa, I., and Cunha, F.: Geophysical investigation using the GPR method: a case study of a lead contamination in Santo Amaro, Bahia, Brazil, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5310, https://doi.org/10.5194/egusphere-egu2020-5310, 2020.

EGU2020-9019 | Displays | GI5.1

Drowned Dunes: Integrating 3D GPR and core data to reconstruct a late Holocene buried dune environment.

Luis Rees-Hughes, Natasha Barlow, Adam Booth, Jared West, George Tuckwell, and Tim Grossey

During the last two decades, ground-penetrating radar (GPR) methods, have grown in popularity for acquiring high-resolution images of the stratigraphy, internal structure and wider context of geomorphology, as well as the reconstruction and evolution of buried landscapes. GPR offers centimetre-scale resolution of the subsurface, allowing 3D visualization of abrupt changes in palaeo-environments. Although often complemented by core data, GPR interpretations can also be extended beyond regions of ground-truth control. However, for all these advantages, GPR data interpretation can be non-intuitive and ambiguous, with the technique seldom giving images that immediately resemble the expected subsurface geometry. Interpretation can be made yet more onerous when handling the large 3D data volumes that are commonly available with modern GPR technology.

In this paper, we outline the development of a semi-automated GPR feature-extraction tool, based on the image processing techniques ‘Edge Detection’ and ‘Thresholding’. Developed initially for medical image analysis, we investigate them as a means of assisting the analysis of GPR data for subsurface geomorphic features. Given that GPR reflectivity can be related to changes in lithology and/or pore fluids, the structure and extent of subsurface depositional environments can be efficiently estimated using these algorithms. When benchmarked against representative core control, the 3D architecture of the palaeo-landscape can be reconstructed from the GPR dataset.

We present a 500 MHz GPR dataset collected over a buried Holocene coastal dune system in Llanbedr, Gwynedd, North Wales, which has since been reclaimed for use as an airfield. Core data, with maximum depth 2 m, suggest rapid vertical changes from sand to silty-organic units, and GPR profiles suggest that similar lateral complexity is likely across the dataset. By applying thresholding methods to top-down depth slices, the environment is effectively characterised. Furthermore, automatic extraction of the local reflection power with depth yields a strong correlation with the vertical variation of organic content. Similar analyses away from core control could, therefore, deliver a powerful proxy for parameters derived from invasive core logging.

How to cite: Rees-Hughes, L., Barlow, N., Booth, A., West, J., Tuckwell, G., and Grossey, T.: Drowned Dunes: Integrating 3D GPR and core data to reconstruct a late Holocene buried dune environment., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9019, https://doi.org/10.5194/egusphere-egu2020-9019, 2020.

GI5.2 – Innovative instrumentations, techniques, geophysical and remote sensing methods, material characterization, models and ICT tools for the smart and resilient cities of the future.

EGU2020-3383 | Displays | GI5.2 | Highlight

Smart City Technologies for Cultural Heritage Protection

Jürgen Moßgraber, Tobias Hellmund, Philipp Hertweck, and Hylke van der Schaaf

Climate change (CC) will morph the environmental landscape, thus leading to climate stress imposed on Cultural Heritage (CH). Especially, tangible CH, like castles, palaces, monuments and churches as well as gardens are exposed to CH effects. Such effects are heat waves, flooding, higher sea level, just to name a few.

The management and preservation of such CH buildings and whole sites, particularly in the context of CC, is a complex task in which authorities and decision makers need to aggregate and oversee information from diverse sources and domains. Yet, only by considering all relevant and available information, stakeholders can make well-grounded decisions. This imposes a complex task upon the authorities, not only due to the diversity and heterogeneity, but also to the quantity of available data.
Only if the current and future situation of the CH in focus is understood, strategies for protecting them can be developed.

The first challenge is to apply different kind of sensors to the buildings and gardens to collect data about the weather (temperature, precipitation, etc.), the situation of walls incl. cracks and the state of plants. After that, this data needs to be managed and made accessible in homogeneous way for further processing and analysis.
The domain of smart city research faces the exact same problems. Sensors are applied all over the city for example about traffic, infrastructure, air and water quality and weather data. In contrast to CH the community is much larger and the industry is involved as well.

Therefore, it is beneficial to look into technologies developed for smart cities and analyze how they can be applied to the monitoring of CH sites. For retrieving, managing and processing sensor data there are open standards evolving, for example the SensorThings API standard by the Open Geospatial Consortium (OGC). Currently, many tools evolve around such standards from which some are available as open source.
First results of successfully applying these technologies from different CH and smart city projects will be presented.

How to cite: Moßgraber, J., Hellmund, T., Hertweck, P., and van der Schaaf, H.: Smart City Technologies for Cultural Heritage Protection, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3383, https://doi.org/10.5194/egusphere-egu2020-3383, 2020.

EGU2020-4826 | Displays | GI5.2

Evaluation of the GPS errors influence on the resistivity in ERT investigation of funeral mounds

Veronica Pazzi, Lorenzo Ciani, Luca Cappuccini, Mattia Ceccatelli, Gabriele Patrizi, Giulia Guidi, Nicola Casagli, and Marcantonio Catelani

During the 7th century BC, Vetulonia (Tuscany, Italy) was one of the most important cities in northern Etruria and its powerful princes commissioned monumental tumuli that reached more then 90 metres in diameter, among the largest in the ancient world. Between the end of 1800 and the beginning of 1900, many of these funeral mounds have been investigated. The one of Poggio Pepe (eastern side of the Vetulonia hill) has never been thoroughly investigated. Therefore, the internal structure is still unknown and, given the absence of a depression at the top of the mound, the inside of the chamber could be still well preserved, with the roof intact.

A joint project among three different departments of the University of Florence, lead to a new investigation campaign on this tumulus. Four radial 2D- electrical resistivity tomography (ERT) were carried out. The main aims were to verify the structures conservation state and to identify the ancient tomb access. The roof conservation status is of great importance for the excavation strategy: if research will ascertain that the roof is still preserved, the excavation of the funeral chamber will start from the corridor and appropriate works will have to be planned to support the central cover. On the contrary, excavation will begin from the top of the mound. Moreover, since the exploration of tumuli is a challenging geophysical problem, other goal was to evaluate the influence, on the acquired 2D-ERT data, of the error in collecting electrode coordinates (GPS error). It is well known that the final results resolution and accuracy depend on the spatial distribution of the acquisition points on the ground surface. The precision in locating these points plays a key role, too. Nevertheless, it is hard to find in literature papers that discuss the influence on the final results of the errors in locating acquisition points.

The geophysical surveys identified remains of the wall that originally surrounded the great tumulus, and intercepted radial surface structures that have been interpreted as the highest part of the sidewalls of the tomb access corridor. Moreover, an anomaly that could represents the walls of the funeral chamber (3 m - 4 m per side) was recognized. Further development of the investigation and data analysis will allow a greater definition of the internal structures and particular attention will be given to the state of the tomb roof.

The results of the preliminary analysis of the influence of GPS error on the apparent resistivity data suggest that, in case of consistent GPS uncertainty, caused by physical and atmospheric conditions, the shallow apparent resistivity is strongly influenced by a wrong deployment of electrodes. Therefore, in case of archaeological application, where the investigation depth is limited to the first meters below the ground surface, the measurement campaign should be rescheduled in a different period, when different conditions will occur. This leads to an improvement of ERT data quality and, consequently, to a better accuracy in the localization of the archaeological target, with a minimization of the excavation cost.

How to cite: Pazzi, V., Ciani, L., Cappuccini, L., Ceccatelli, M., Patrizi, G., Guidi, G., Casagli, N., and Catelani, M.: Evaluation of the GPS errors influence on the resistivity in ERT investigation of funeral mounds, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4826, https://doi.org/10.5194/egusphere-egu2020-4826, 2020.

EGU2020-7010 | Displays | GI5.2

A multi-disciplinary materials study as a contribtion to evaluate degradation issues of monuments and archaeological sites towards their preservation

Antonella Curulli, Giampiero Montesperelli, Sara Ronca, Fernanda Carvalho, Joao P. Veiga, Nicola Cavalagli, Filippo Ubertini, Hugo Aguas, Elisabeth Kavoulaki, and Giuseppina Padeletti

The preservation of archaeological sites, often considered as open-air museum, is a priority and a challenge due to their exposure to environmental actions and natural hazards. Every day, the artifacts populating these sites, which can have either structural or decorative functions, are subjected to continuous degradation processes, related to frost-thaw cycles, humidity and temperature variations, causing a deterioration of the materials mechanical properties. Anthropogenic pressure (visitors, human actions) can acts towards his direction, as well. In order to evaluate the ongoing process of degradation affecting a specific site, the study of the actual conditions of the materials is typically one of the first steps of the analysis. With this perspective, in this work, the results of the investigations carried out on the constituent materials of the Knossos Palace in Crete are presented. The Knossos Palace is one of the most important archaeological sites in Crete. The main excavation work took place at the beginning of the 20th century, directed by Sir Arthur Evans. The importance of this site led him and his collaborators to design and perform preservation actions, which included the reconstruction of relevant parts of the Knossos Palace. In addition for preserving the site, reconstructions were a way of highlighting the palace magnificence and the importance of the Minoan civilization. At that time concrete was already one of the most widely used building material. Considered a durable material, the concrete was used in the construction of reinforcement structures and new architectural elements, often placed in direct contact with the original ones. Nevertheless, the restoration/reconstruction made by Evans, using concrete, is nowadays considered an integral part of the monument and its history, to be studied and protected.

In the context of the HERACLES Project [1], samples of stones and concrete used in the Palace of Knossos were analysed to determine their morphological and chemical characteristics and their mechanical properties. For this purpose, an integrated approach, i.e. the use of several analytical techniques, was considered essential to support the material preservation actions.

[1]European Project HERACLES has received funding from the European Union Framework Programme for Research and Innovation HORIZON 2020 under GA n° 700395

 

How to cite: Curulli, A., Montesperelli, G., Ronca, S., Carvalho, F., Veiga, J. P., Cavalagli, N., Ubertini, F., Aguas, H., Kavoulaki, E., and Padeletti, G.: A multi-disciplinary materials study as a contribtion to evaluate degradation issues of monuments and archaeological sites towards their preservation, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7010, https://doi.org/10.5194/egusphere-egu2020-7010, 2020.

EGU2020-9294 | Displays | GI5.2

Deep geophysical investigation in urban area: Ferrara city example

Enzo Rizzo, Luigi Capozzoli, Gregory De Martino, Sabatino Piscitelli, Jessica Bellanova, Riccardo Caputo, Vincenzo Lapenna, Lorenzo Petronio, Luca Baradello, Alessandro Affatato, Gianfranco Morelli, and Federico Fischanger

The role of applied geophysics for the new scenario of the increasing global urbanization is going to grow day by day. In this scenario a detailed knowledge of the geological subsoil and its iteration with urban infrastructures became a fundamental issue for urban planning. A novel sub-discipline, called Urban Geophysics (Lapenna, 2017) , has recently been developing in the field of geophysics for analyzing limits and potentialities of well-known geophysical techniques in urban and industrialized areas. The application of some geophysical methods allows the recognition of geological structures from near surface down to more several hundred meters. The urban environment, characterized by a difficult logistic and a high level of noise, has a strong impact on the applicability of the geophysical prospecting methods and on the data quality.

This paper presents the results obtained by Deep Electrical Resistivity Tomography (DERT) and P-wave seismic reflection surveys performed in the city of Ferrara, which is interested in the management of geothermal resources and in the mitigation of seismic risk (CLARA-“Cloud Platform and smart underground imaging for natural risk assessment” Project funded by Italian MIUR). Along the eastern flank of the city walls, DERT and Reflection Seismic profiles were carried out in order to improve the geological information of the urban context.

DERT applications are not very common and there are only few published examples. It consists to inject direct current (square wave) into the ground, depending on the arrangement of the input points and the electrical resistivity of the subsoil, the shape of the electric field that is measured at the surface. The peculiarity of the DERT is the use of large electrode distances (>200 m) and long profiles (>3000 m) in order to reach large investigation depths (>300 m).

Seismic reflection investigations offer a powerful non‐invasive tool suitable for mapping the subsurface geological framework from the very near‐surface to hundreds of metres below surface. Recently several seismic surveys was performed in urban environment by using frequency-controlled vibroseis sources both in P- and SH-wave.

Along the eastern flank of the city walls, a DERT (5500m long) and a reflection seismic (2500m acquired by a MiniVib source in P-wave configuration) profiles were carried out in order to improve the geological information of the urban context. The joint interpretation of DERT and seismic data allowed to reconstruct the 'local' stratigraphic-depositional evolution until a depth of about 1 km, and to highlight the occurrence of a sin-depositional Quaternary tectonic tilting associated to the growth of a fault-propagation fold.

How to cite: Rizzo, E., Capozzoli, L., De Martino, G., Piscitelli, S., Bellanova, J., Caputo, R., Lapenna, V., Petronio, L., Baradello, L., Affatato, A., Morelli, G., and Fischanger, F.: Deep geophysical investigation in urban area: Ferrara city example, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9294, https://doi.org/10.5194/egusphere-egu2020-9294, 2020.

EGU2020-10663 | Displays | GI5.2

An integrated geophysical approach for structural behavior characterization of the Gravina bridge (Matera, Southern Italy)

Vincenzo Serlenga, Maria Rosaria Gallipoli, Nicola Tragni, Rocco Ditommaso, Tony Alfredo Stabile, Angela Perrone, Domenico Pietrapertosa, and Raffaele Franco Carso

Civil infrastructures (i.e bridges, galleries ...) are crucial parts of the road asset and their possible degradation, with related consequences, may have great social, economical and safety impacts. On these grounds, the periodic monitoring of such infrastructures, from a static and dynamic point of view, is required for identifying possible changes in the structure properties, in order to prevent serious damages and disasters.

In this study we propose an integrated geophysical approach by using non-invasive and non-destructive seismic and electromagnetic techniques with standard and low-cost sensors. It has been implemented to understand the static and dynamic properties of the Gravina bridge and its interaction with foundation soils. Gravina Bridge is a bow-string bridge located few km far from Matera (Southern Italy) and developing for 144 m along a steel-concrete deck. First, the properties of the foundation soils were studied by carrying out three high-resolution geo-electrical tomographies, one bi-dimensional seismic array and two single-station seismic noise measurements. Then, the structural characteristics of the bridge were inferred through seismic and electromagnetic sensing. The former was performed by means of recordings by accelerometers and velocimeters. The accelerometers were installed in a continuous acquisition mode, along the deck and on the top of the arch. In that way, several local and regional earthquakes were recorded and detected. The velocimeters were deployed along different seismic array configurations for on-demand ambient noise recordings, in normal traffic conditions and during vibration tests. The latter were executed by using vehicles as dynamic sources.

The electromagnetic sensing was performed by using the Microwave Radar Interferometer: it was placed below the deck to measure the displacements of all the scenario illuminated by the antenna beam providing a continuous mapping of the static and dynamic displacements of the entire target.

The acquired dataset was analyzed both in frequency and time-frequency domain in order to characterize the stationary and non-stationary response of the monitored bridge in terms of fundamental frequencies of vibration, equivalent viscous damping factors and modal shapes. The consistency between the results retrieved by different geophysical techniques provides therefore an importan hint about the reliability of the described approach.

How to cite: Serlenga, V., Gallipoli, M. R., Tragni, N., Ditommaso, R., Stabile, T. A., Perrone, A., Pietrapertosa, D., and Carso, R. F.: An integrated geophysical approach for structural behavior characterization of the Gravina bridge (Matera, Southern Italy), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10663, https://doi.org/10.5194/egusphere-egu2020-10663, 2020.

EGU2020-12095 | Displays | GI5.2

Subsurface targets detection using Faster R-CNN for Unmanned Aerial Vehicle Magnetic Survey

Yaoxin Zheng, Xiaojuan Zhang, Yaxin Mu, and Wupeng Xie

Unmanned Aerial Vehicle (UAV) has become a viable platform for magnetic surveys, but the interference generated during flight and lack of the interpretation method for survey data limits its application. In this paper, we present a structure of a half-fixed boom for the UAV-magnetometer system. Compared to suspend the magnetometer on a long rope or cable, our new structure reduces interference and positional error meanwhile increases flight stability. The interference field was removed through compensation based on leveling, with root mean square error significantly reduced from 2.7889 nT to 0.2809 nT. The Faster R-CNN network was adapted for the detection of subsurface buried objects (i.e. Unexploded Ordnance) in UAV magnetic surveys, our Faster R-CNN object detection network is composed of a feature extraction network followed by two subnetworks, the feature extraction network we use is a pre-trained CNN called ResNet-50, the first subnetwork is a region proposal network (RPN) and the second subnetwork is trained to predict the actual class of each object proposal. A labeled dataset that contains 740 images was used for training and each image contains one or more labeled instances of mag anomaly, data augmentation is used by randomly flipping the image and associated box labels horizontally to improve network accuracy, the trained object detector was evaluated on both simulated and field test images. All implementations in this work were accomplished through MATLAB Deep Learning Toolbox using a PC with a GPU compute capability 7.5. Preliminary results reveal that the proposed technique can automatically confirm the number of subsurface targets, in the meantime results from different field tests show its robustness. Significant improvements have made compared to traditional computer vision methods and hence become quite promising to be applied in the field of UAV magnetic survey.

How to cite: Zheng, Y., Zhang, X., Mu, Y., and Xie, W.: Subsurface targets detection using Faster R-CNN for Unmanned Aerial Vehicle Magnetic Survey, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12095, https://doi.org/10.5194/egusphere-egu2020-12095, 2020.

In the last years, existing structures and transport infrastructures, especially those made using reinforced concrete, have experienced significant safety criticalities implying also a relevant social and economic impacts. Structural Health Monitoring techniques represent a reliable response to the problem available to scientists and engineers. A multidisciplinary approach combing knowledge from several research fields and using different kind of technologies would be preferable for this type of application. Most of developed methods for structural damage detection on civil structures and infrastructures is generally based on the evaluation of displacements, eigenfrequencies, damping factors, mode shapes, etc., and their variation over time, by means of on-site installed sensors. In recent years, thanks to the rapid evolution of interferometric SAR processing techniques, a large amount of “satellite measurements” are available for both geophysical phenomena and building monitoring in terms of displacement rate over time. This paper presents an overview on the 2019-2021 WP6 Reluis Project aiming to contribute to the discussion about the opportunity and the modalities to merge information retrieved both by on-site and remote sensing measurements and to define a shared strategy to detect damage on existing structures and infrastructures in operational conditions.

How to cite: Ponzo, F. C. and Ditommaso, R.: Structural Health Monitoring of existing structures and infrastructures combining on-site and satellite data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13600, https://doi.org/10.5194/egusphere-egu2020-13600, 2020.

EGU2020-17858 | Displays | GI5.2

The role of geophysics for urban environment characterization: the case study of Matera (southern Italy)

Giuseppe Calamita, Maria Rosaria Gallipoli, Angela Perrone, Vincenzo Serlenga, Tony Alfredo Stabile, Nicola Tragni, Serena Panebianco, Jessica Bellanova, Sabatino Piscitelli, Francesco Izzi, Lorenzo Amato, Giuseppe Lascaleia, Donato Maio, and Vito Salvia

The global urbanization process, along with the environmental impacts it carries with it, requires the adoption of innovative programming strategies for the sustainable and efficient management of natural resources and to improve the resilience of cities to natural disasters. In this scenario where the acquisition of a deeper and as thorough as possible knowledge of the territory on the problems connected with the phenomena of hydrogeological instability and natural risk in general that can affect the inhabited centers pose new challenges both at the level of government and for the scientific community. Further, it is also important to organize and make these complex information easily accessible to stakeholders, i.e. administrators, planners and civil protection.

In the framework of two national projects, CLARA (CLoud plAtform and smart underground imaging for natural Risk Assessment) and SPOT (Development of a Platform for the provision of innovative services based on Earth Observation data), a systemic approach based on the integration of the latest enabling technologies (remote sensing and ground-based, active and passive, direct and indirect, multi-sources and multi-resolution) for the geo-physical characterization (seismic and electromagnetic) of the surface and near-surface and for the dynamic characterization of soil structure/infrastructure interactions was applied in the urban area of the city of Matera (southern Italy). By adopting the open-government and open-data paradigms, all the information collected have been eventually organized and shared in a web-gis along with geospatial data already available on different and independent web-services of local government authorities (region and municipality).

How to cite: Calamita, G., Gallipoli, M. R., Perrone, A., Serlenga, V., Stabile, T. A., Tragni, N., Panebianco, S., Bellanova, J., Piscitelli, S., Izzi, F., Amato, L., Lascaleia, G., Maio, D., and Salvia, V.: The role of geophysics for urban environment characterization: the case study of Matera (southern Italy), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17858, https://doi.org/10.5194/egusphere-egu2020-17858, 2020.

In the last decade, the Italian territory has been severely damaged by the occurrence of hydrogeological instability phenomena with a growing impact on human activities and the economy. More and more often the phenomena have involved urban areas with considerable effects on the population that was forced to leave home for safety reasons. Furthermore, damage to the infrastructures have worsened the living conditions isolating the population for many days. In the latest ISPRA technical report of 2018 (http://www.isprambiente.gov.it/it/pubblicazioni/rapporti/dissesto-idrogeologico-in-italia-pericolosita-e-indicatori-di-rischio-edizione-2018), which analyses the spatial distribution of landslides throughout Italian regions, great attention was paid to the impact of landslides on the urban fabric. According to this report, there are 83 towns out of 131 (63%) in Basilicata region where the landslides involve the continuous and discontinuous urban fabric as well as industrial or commercial areas. This high percentage is especially due to the geological settings, the type of human settlements characterizing the region and, especially during the last years, to the occurrence of intense rainfall events. Indeed, starting from December 2013 when as a consequence of intense rainfall events a fast landslide affected the southwest area of Montescaglioso town in the Matera hill, other important and dangerous phenomena have affected the Basilicata territory. Among these the Stigliano (MT) and the Pomarico (MT) phenomena, respectively occurred in February 2014 and in January 2019, are worth mentioning. All these landslides have caused significant damage to road infrastructures, civil structures and commercial activities, requiring the proclamation of a state of emergency, the evacuation of some houses and the intervention of Italian National Civil Protection. From a logistically point of view the study of landslides occurring in urban areas can be more complicated than in the rural areas. The presence of structures and infrastructures involved in the land movement, also posing risk and safety issues for personnel, can make detailed investigations difficult. The adoption of an integrated approach based on the combined application of different non-invasive in situ investigation techniques would, in most cases, help to overcome such limitations, to increase the number of information and to reduce the specific drawbacks of each technique such as, for example, the deterioration of data quality due to the high noise level. A successful geophysical application where results are well integrated and compared with direct information can help to correctly reconstruct the geological model of the subsoil. The geophysical model can indeed provide information on the geological setting of the area, helping to answer the most frequent questions of civil protection technicians such as: how deep is the sliding surface? how much material was involved in the movement? are there any areas that could be affected by instability phenomena?

How to cite: Perrone, A.: Ten years of civil protection support activities in landslide areas of Basilicata, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18656, https://doi.org/10.5194/egusphere-egu2020-18656, 2020.

EGU2020-19274 | Displays | GI5.2

Current and Future Challenges in Modern Port Development and Cultural Heritage Preservation within port infrastructures.

George Alexandrakis, Stelios Petrakis, Stavros Liritzakis, and Nikolaos Kampanis

Climate change impact is functioning as risk-multiplier to problems which are already apparent and affect infrastructures. In cases of infrastructures within cultural heritage sites, the problem is more complicated. Sea Level Rise and increased storm events can damage structures not designed to withstand prolonged structural pressure, erosion and immersion. Risks affecting coastal cultural heritage may stem from exposure to several hazards and it is important to facilitate a holistic understanding of the factors driving them. Wave energy and overtopping of coastal structures act as potential hazards for people, property and infrastructure. When, particularly, monuments or landmarks are present within the infrastructures, mitigation measures and monitoring are essential. Depending on the level of acceptable risk and the required degree of certainty related to wave overtopping, coastal engineers rely on predictions derived from semi-empirical desktop methods and numerical models for answers. Moreover, the anticipated increase in extreme events due to climatic change makes protection and prevention actions even more necessary. Additionally, restrictions in fund availability and landscape preservation for coastal monuments, make the designing of such interventions more demanding. In this work, the combination of risk assessment analysis related to increasing sea level and storm frequency, wave numerical modelling, breakwater design and economic sustainability is presented. As case studies, the Venetian Coastal port/Fortress of the city of Heraklion (1523 A.D.) and Venetian port of Rethimnon (13th century A.D.), both located at the North coast of the island of Crete, Greece, are considered. Both ports are tourism hotspots within the region. Numerical modelling results were generally calculated to be consistent with overtopping wave measurements. For the analysis of the wind regime in the near and far future, climatic modelling has been used indicating that, for the coastal area of central Crete, the wind regime is expected to change in the near and far future; an increase not only in wind speeds but also in the prevailing wind directions, the latest affecting the monuments the most. Based on results from on-site measurements and numerical modelling and forecasting, mitigation actions have been proposed, including an expansion of the submerged armouring of the ports infrastructures and the use of natural based solutions for low slope areas, in order to reduce wave energy, run-up and overtopping, so that the monuments can remain functional, safe and accessible for longer periods of time.

How to cite: Alexandrakis, G., Petrakis, S., Liritzakis, S., and Kampanis, N.: Current and Future Challenges in Modern Port Development and Cultural Heritage Preservation within port infrastructures. , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19274, https://doi.org/10.5194/egusphere-egu2020-19274, 2020.

EGU2020-21464 * | Displays | GI5.2 | Highlight

UAV Radar imaging for cultural heritage: a first prototype

Carlo Noviello, Giuseppe Esposito, Ludeno Giovanni, Gennarelli Gianluca, Fasano Giancarmine, Renga Alfredo, Soldovieri Francesco, and Catapano Ilaria

Nowadays, the use of Unmanned Aircraft Vehicle (UAV) based sensing technologies is widely considered in most disparate fields, including archaeology and cultural heritage inspections. The main advantages offered by UAV technology are the possibility of investigating large areas in a very short time,  the simplification of the organization and implementation of the measurement campaigns thus reducing their costs, and finally the increasing availability of autonomous systems that push more and more towards plug and fly solutions.

The widespread remote sensing technologies mounted on-board UAV systems are essentially optical, thermal and multi-spectral sensors, which are passive technologies designed to measure the signal emitted into the optical and (near and far) infrared portions of the electromagnetic spectrum. These technologies exploit techniques like aero-photogrammetry to get high resolutions images of the surface features of the investigated scene and provide useful information to evaluate structural and material degradation, such as surface cracks, humid zones and biological patinas.

Radar systems represent a further technological solution, which exploits the penetration capability into non-metallic media of the microwaves, thus offering the key advantage to perform surface and sub-surface inspections. However, UAV based radar systems are still under development due to the numerous challenges related to the acquisition modality and data processing. Being radar an active technology, both transmitting and receiving units must be installed on-board the UAV and this introduces not trivial issues related to payload and assets constrains. Moreover, in order to obtain focused images, a high precision knowledge of the UAV position during its flight must be available.

As a contribution to this topic, an ultra-light radar system mounted on a micro drone has been developed and its imaging capabilities have been assessed in controlled conditions. The UAV radar imaging system is an enhanced version of that presented in [1]. Specifically, the main components of the assembled prototype are the UAV DJI F550- hexacopter platform and the Pulson P440 radar sensor. The radar system has been equipped with two log-periodic antennas pointed at nadir, and it operates in the frequency range of [3.1, 4.8] GHz. Moreover, to accurately reconstruct the UAV platform positioning, the Differential GPS technology has been also implemented by exploiting two GPS receivers placed one onboard the platform and the other one in a fixed ground station. Finally, the data processing is cast as the solution of an inverse scattering problem by exploiting the Born Approximation to model the wave-material interaction. The results of some flight tests will be presented at the conference.

[1] G. Ludeno, I. Catapano, A. Renga, A. Vetrella, G. Fasano, and F. Soldovieri, “Assessment of a micro-UAV system for microwave tomography radar imaging”, Remote Sensing of Environment, vol 212, 2018, pp. 90-102.

Acknowledgment: The authors would like to thank the VESTA project “Valorizzazione E Salvaguardia del paTrimonio culturAle attraverso l’utilizzo di tecnologie innovative” by which the present work has been financed.

 

How to cite: Noviello, C., Esposito, G., Giovanni, L., Gianluca, G., Giancarmine, F., Alfredo, R., Francesco, S., and Ilaria, C.: UAV Radar imaging for cultural heritage: a first prototype, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21464, https://doi.org/10.5194/egusphere-egu2020-21464, 2020.

EGU2020-22198 | Displays | GI5.2

QERT - Quadrupole Electrical Resistivity Tomography

Viktor Nawa and Andreas Junge

The quadrupole technique for geoelectrics yields the apparent resistivity in a tensorial form in contrast to the scalar apparent resistivity obtained from classical geoelectrics. The quadrupole method in geoelectrics has been applied in the past only for long offsets between transmitter and receiver. We scaled down the method to profile-style and grid-style short offset applications. Analysis of the invariants of the apparent resistivity tensor and its representation as ellipse can be used to obtain an estimate of the dimensionality of the subsurface conductivity distribution. We present the basic theory of the quadrupole ERT technique along with numerical and field examples highlighting the advantages over classic geoelectrical survey methods.

How to cite: Nawa, V. and Junge, A.: QERT - Quadrupole Electrical Resistivity Tomography, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22198, https://doi.org/10.5194/egusphere-egu2020-22198, 2020.

EGU2020-22398 | Displays | GI5.2

Strengthening resilience of Cultural Heritage at risk in an extreme changing environment

Alessandra Bonazza, Alessandro Sardella, Paola De Nuntiis, Elisa Palazzi, and Jost von Hardenberg

Natural and man-made hazards, anthropogenic effects and extreme climate change events, are persistently putting cultural heritage under pressure, with an increasing frequency over time. In addition, such disasters and catastrophes impose new and continuously changing conservation challenges and urgently needs for innovative preservation and safeguarding approach, particularly during extreme climate conditions. The present contribution aims at illustrating the working methodology and the solutions specifically dedicated to the safeguarding of cultural heritage exposed to extreme climate changes, developed within the Interreg Central Europe ProteCHt2save and in further implementation within the Interreg Central Europe STRENCH (starting date 1st March 2020).  The outcomes (WebGIS tool, for risk mapping, hazard maps, methodology for vulnerability ranking, strategies for disaster risk reduction) of both projects are principally dedicated to assists local stakeholders in improving their know-how on the process of definition of priorities of intervention and strategies within the risk management cycle (preparedness/emergency/recovery). By the achievement of the planned objectives, ProteCHt2save and STRENCH are expected to proactively

target the needs and requirements of stakeholders and policymakers responsible for disaster mitigation and safeguarding of cultural heritage assets and to foster the active involvement of citizens and local communities in the decision-making process.

How to cite: Bonazza, A., Sardella, A., De Nuntiis, P., Palazzi, E., and von Hardenberg, J.: Strengthening resilience of Cultural Heritage at risk in an extreme changing environment, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22398, https://doi.org/10.5194/egusphere-egu2020-22398, 2020.

EGU2020-14021 | Displays | GI5.2

Vesta Project - Enhancement and safeguarding of cultural heritage through innovative technologies

Francesco Soldovieri, Nicole Dore, Valerio Corini, Ilaria Catapano, Rosa Lasaponara, Enzo Rizzo, Federico Saccoccio, Francesca Cocco, and Annamaria Capodanno

The VESTA project (Valorizzazione E Salvaguardia del paTrimonio culturAle attraverso l’utilizzo di tecnologie) deals with the experimental integration of advanced technologies designed for safeguarding and prospecting sub-soil and ancient structures as well as the management of the information derived from the carried out investigations. The final goal is to support the end users with regard to their conservation, safeguard and discovery activities.

The pilot site test of the Project is the Archaeological Park of Paestum, which is located in the Southeast of the Gulf of Salerno, Italy, and was built by the Greeks and later strengthened by the Lucani and the Romans. Today, the Archaeological Park of Paestum is recognised by UNESCO as part of the World Cultural Heritage thanks to the excellent state of conservation of its structures, especially the three majestic temples: the Temple of Hera (sixth century BC), the Temple of Neptune (fifth century BC) and the Temple of Ceres (sixth century BC). These are remarkable examples of Doric style architecture.

The technological skills made available by the VESTA team are based on:

  • Earth observation tools, such as satellites (optical and radar) for the large-scale identification of critical issues, both natural and anthropic, involving cultural heritage and around them;
  • Mini-micro UAV (Unmanned Aerial Vehicle) equipped with multispectral, thermal and radar optical sensors and aimed at detailed soil and wall structure analysis;
  • High and low frequency terrestrial radar (GPR - Ground Penetrating Radar) for inspections of masonry and subsoil structures respectively;
  • Electrical Resistivity Tomography (ERT) for the investigation of the subsoil.

These technological solutions are key tools for identifying and mapping possible degradation phenomena of ancient structures identifying dangers related to the surrounding environment that could compromise the state of conservation of the monuments inside the park. Therefore, their use as well as the cooperative exploitation of the provided results allow an improvement of knowledge about the critical aspects of the territory and the state of conservation of the artefacts, in order to facilitate the planning of maintenance interventions. Specifically, the gathered data are made available to site manager via St’ART ™ web platform, which allows a simple consultation of results collected during VESTA project campaigns thanks to reports and thematic maps.

Acknowledgment: The authors would like to thank the VESTA project “Valorizzazione E Salvaguardia del paTrimonio culturAle attraverso l’utilizzo di tecnologie innovative” by which the present work has been financed. The VESTA project is co-founded by the Campania Region within the POR-FESR 2014-2020 program.

 

How to cite: Soldovieri, F., Dore, N., Corini, V., Catapano, I., Lasaponara, R., Rizzo, E., Saccoccio, F., Cocco, F., and Capodanno, A.: Vesta Project - Enhancement and safeguarding of cultural heritage through innovative technologies, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14021, https://doi.org/10.5194/egusphere-egu2020-14021, 2020.

It is widely known that, in GPR prospecting [1-2], sometime it is not possible to make use of the customary odometer for the recording of the position of the measurement points along the observation line. Consequently, in these cases the human operator is compelled to make use of point markers placed at known positions (measured with a tape) along the observation line. In particular, this can happen on the sand of a desert and on the polar ice [3], but it might happen also just due to some ill-functioning of the odometer. Notwithstanding, quite rarely the effects of the use of the point markers have been examined on the basis of some experimental test. At the conference, we will show an experiment where the same observation line has been gone through several times, first making use of the odometer included in the exploited GPR system and then making use of marker points. A third time, the same path was still travelled without odometers and taking the marker points without making use of any laptop command. These were replaced just by stopping for some seconds the GPR in any marker point (but keeping it switched on). This option can be useful in cases where e.g. the command has to be given through a touchscreen. The observation line was 15 m long, and was placed on a flat smooth and tough floor. This means that the line offered favourable conditions for the use of the odometer, and so the positions of the anomalies identified making use of the odometer are considered as the correct positions of the buried targets. This has allowed a quantification of the displacements from the correct position of the buried anomalies when making use of marker points taken with a step of one meter from each other. A  larger and deeper dealing is available in [4].

References

[1] R. Pierri, G. Leone, F. Soldovieri, R. Persico, "Electromagnetic inversion for subsurface applications under the distorted Born approximation" Nuovo Cimento, vol. 24C, N. 2, pp 245-261, March-April 2001.

[2] R. Persico, M. Ciminale, L. Matera, A new reconfigurable stepped frequency GPR system, possibilities and issues; applications to two different Cultural Heritage Resources, Near Surface Geophysics, vol. 12, n. 6, pp. 793-801 (doi: 10.3997/1873-0604.2014035), December 2014.

[3] H. Jol, Ground Penetrating Radar: Theory and applications, Elsevier, 2009.

[4] R. Persico, Ground Penetrating Radar: Physics and Practical Aspects, Springer Handbook of Cultural Heritage Analysis, edited by Sebastiano D’Amico and Valentina Venuti, Springer, 2020.

How to cite: Persico, R.: Point markers in replacement of odometer driven positioning: effects and possible problems, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1663, https://doi.org/10.5194/egusphere-egu2020-1663, 2020.

EGU2020-1664 | Displays | GI5.2

Use of multi-length TDR data aimed to infer the dispersion law of nonmagnetic materials

Iman Farhat, Raffaele Persico, Lourdes Farrugia, and Charles Sammut

This contribution presents a method of multi-length transmission lines, filled with or embedded in the material under test (MUT), based on time domain reflectometry (TDR), to measure the dispersion law of a nonmagnetic material. This approach is essential and can be exploited in both radiofrequency and microwave applications. The proposed technique expands on studies presented in [1-2], where dielectric, magnetic and conductive losses are accounted for by the complex relative permittivity and permeability of the MUT.

Many materials of interest in geophysical [3-4] and biomedical [5-6] applications are non-magnetic but preliminary measurements with the proposed technique can help to determine if the MUT indeed has magnetic properties. Moreover, it is shown that establishing the non-magnetic nature of the MUT constitutes meaningful a-priori information that allows disambiguating experimental results, even with limited data in the frequency range of interest.

Results relative to two different types of multi-length measurement data, namely data acquired by considering different lengths of a TDR probe entirely embedded in (or embedding) the MUT and data achieved from a sequential progressive embedding of the probe in the MUT (or, vice-versa, of the MUT in the probe) are presented to illustrate the method. The pros and cons of presented cases are also discussed.  

Acknowledgements

This work is supported by the European Cost Action “Mywave” CA17115.

References

[1] R. Persico, M. Pieraccini, Measurement of dielectric and magnetic properties of Materials by means of a TDR probe, Near Surface Geophysics, vol. 16, n.2, pp.1-9, DOI:10.3997/1873-0604.2017046, 2018.

[2] R. Persico, I. Farhat, L. Farrugia, S. d’Amico, C. Sammut, An innovative use of TDR probes: First numerical validations with a coaxial cable, Journal of Environmental & Engineering Geophysics, doi.org/10.2113/JEEG23.4.437, 23 (4): 437-442, 2018.

[3] R. Pierri, G. Leone, F. Soldovieri, R. Persico, "Electromagnetic inversion for subsurface applications under the distorted Born approximation" Nuovo Cimento, vol. 24C, N. 2, pp 245-261, March-April 2001.

[4] R. Persico, M. Ciminale, L. Matera, A new reconfigurable stepped frequency GPR system, possibilities and issues; applications to two different Cultural Heritage Resources, Near Surface Geophysics, vol. 12, n. 6, pp. 793-801 (doi: 10.3997/1873-0604.2014035), December 2014.

[5] R. Pethig, "Dielectric Properties of Biological Materials: Biophysical and Medical Applications," in IEEE Transactions on Electrical Insulation, vol. EI-19, no. 5, pp. 453-474, Oct. 1984.
doi: 10.1109/TEI.1984.298769

 [6] C. Gabriel, S. Gabriel and E Corthout, “The dielectric properties of biological tissues: I. Literature survey,” Physics in Medicine and Biology, vol. 41, no. 11, pp. 2231-2249, Nov. 1996.

How to cite: Farhat, I., Persico, R., Farrugia, L., and Sammut, C.: Use of multi-length TDR data aimed to infer the dispersion law of nonmagnetic materials, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1664, https://doi.org/10.5194/egusphere-egu2020-1664, 2020.

EGU2020-2886 | Displays | GI5.2

Non-invasive investigations for enhancing the knowledge and the valorisation of the cultural heritage: first results of the Malta-Italy bilateral project

Raffaele Persico, Giovanni Leucci, Lara De Giorgi, Maurizio Lazzari, Sebastiano D'Amico, and Emanuele Colica

“Non-invasive investigations for enhancing the knowledge and the valorisation of the cultural heritage” is a biennial project financed by the Italian National Research Council (CNR) and by the University of Malta, started in 2018 until to April 2020. It has been  aimed to perform geophysical investigation both in Italy and in Malta in order to enhance the knowledge, and therefore also the preservation and the valorisation of some relevant monuments and archaeological sites in both countries. In particular, we have performed ground penetrating radar [1-2], resistive [3] and passive seismic investigations [4] within or close to archaeological sites, churches, roman monuments and watchtowers and have identified [5], depending on the case, anomalies due to buried rooms, tombs, roads or just geological differences in the subsoil.

Geophysical investigations were also integrated by regional and local geomorphological survey applied to the natural heritage of Gozo Island, such as in the case of the natural arch of Wied il-Mielah and the  terraced high paleosurfaces, on which ancient watchtowers are often present..

In some cases, excavations were possible too, in other cases we hope they will be done in a future. Not all the times the excavations enlightened the hypothesized anomalies, but all the times the anomalies corresponded to some physical target or some physical buried discontinuity of the soil. At the conference, we will provide some insight on the achieved results, with special emphasis on the results achieved during the second year of the project.

References

[1] R. Pierri, G. Leone, F. Soldovieri, R. Persico, "Electromagnetic inversion for subsurface applications under the distorted Born approximation" Nuovo Cimento, vol. 24C, N. 2, pp 245-261, March-April 2001.

[2] R. Persico, M. Ciminale, L. Matera, A new reconfigurable stepped frequency GPR system, possibilities and issues; applications to two different Cultural Heritage Resources, Near Surface Geophysics, vol. 12, n. 6, pp. 793-801 (doi: 10.3997/1873-0604.2014035), December 2014.

[3] G. Leucci, Nondestructive Testing for Archaeological and Cultural Heritage. A Practical Guide and New Perspectives, Springer, 2019.

[4] Villani F., D'Amico S., Panzera F., Vassallo M., Bozionelos G., Farrugia D., Galea P., 2018. Shallow high-resolution geophysical investigation along the western segment of the Victoria Lines Fault (island of Malta). Tectonophysics, 724–725, 220-233 DOI: https://doi.org/10.1016/j.tecto.2018.01.010

[5] Persico R., Leucci G., D’Amico S., De Giorgi L., Colica E., Lazzari M., The watch towers in Malta: a patrimony to preserve for the future. Proceedings of 2019 IMEKO TC-4 International Conference on Metrology for Archaeology and Cultural Heritage Florence, Italy, December 4-6, 2019,pp. 100-102.

 

How to cite: Persico, R., Leucci, G., De Giorgi, L., Lazzari, M., D'Amico, S., and Colica, E.: Non-invasive investigations for enhancing the knowledge and the valorisation of the cultural heritage: first results of the Malta-Italy bilateral project, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2886, https://doi.org/10.5194/egusphere-egu2020-2886, 2020.

EGU2020-4917 | Displays | GI5.2

Subsurface investigation of the Terrace of the Elephants in the Angkor world heritage site using geophysical survey

Kwangwu Lee, Kiju Kim, Byungsuk Park, Wooseok Kim, and Jaehyeung Jeoung

Geophysical survey methods are widely applied into not only underground water exploration and environmental pollution & civil engineering fields of the ground, but also in the archeological field such as exploration of the historic remains. The electrical resistivity tomography(ERT) and seismic surveys were conducted to determine the distribution of underground around the terrace of the elephants. ERT survey was conducted to investigate the natural geological distribution and artificial ground around the terrace of the elephants and seismic survey was conducted to find out the velocity distribution of the terrace of the elephants. ERT resulted in a difference in the traces of artificial ground composition around natural ground and terrace of the elephants. Geophysical survey could be used to infer the range and purpose of the underground composition of historic remains (KOICA Project Number: 2019-00065).

How to cite: Lee, K., Kim, K., Park, B., Kim, W., and Jeoung, J.: Subsurface investigation of the Terrace of the Elephants in the Angkor world heritage site using geophysical survey, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4917, https://doi.org/10.5194/egusphere-egu2020-4917, 2020.

EGU2020-6944 | Displays | GI5.2

Asphalt in trackbed design

Chrysoula Voulgari

Conventional all granular trackbed has been in use around the world for many years, presenting good results although requiring a certain level of ongoing maintenance. Increasing traffic loads and volumes and particularly the introduction of high-speed trains in the last few decades, have resulted in the need for new approaches. To reduce train load-induced stresses in the track subgrade, one approach that has been introduced is the use of a Hot Mix Asphalt (HMA) layer as a partial or full replacement of the granular sub-ballast.

During the past few decades the use of HMA as a sub-ballast layer within the track structure has steadily increased until it has become standard practice in many countries around the world (USA, Japan, Germany, Italy etc.). The HMA mix is designed similarly to the base layer of highway pavements. Specifically, it is designed to be a medium modulus, flexible, low voids, fatigue resistant layer that will accommodate high tensile strains without cracking .

This paper provides a review of the potential use of an asphalt layer to replace the granular sub-ballast during the railway trackbed design.  A literature review of the use of asphalt in trackbed construction and a parametric analysis have been carried out to compare traditional ‘all granular’ and more recent asphalt layer solutions for different subgrade stiffnesses. 

Results indicate various advantages of the use of asphalt in the trackbed; improving trackbed performance and decreasing the overall cost and environmental impact.

How to cite: Voulgari, C.: Asphalt in trackbed design, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6944, https://doi.org/10.5194/egusphere-egu2020-6944, 2020.

EGU2020-7448 | Displays | GI5.2

GEOPHYSICAL MEASUREMENTS IN AN ABANDONED OLD RAILWAY TUNNEL (MARSICO NUOVO, Italy)

Gregory De Martino, Luigi Capozzoli, Valeria Giampaolo, and Enzo Rizzo

In Europe, there are many abandoned railway tunnels. These structures are generally placed in mountainous or hardly accessible territories, where their use was no longer necessary for the improvement of the road communications and the favourite use of the private car. However, in some cases, they could be an important point of observation to monitor the mountains, where important hydrogeological resource are located. This is the case of an old tunnel sited in Marsico Nuovo village, where the rail way “Atena-Marsico Nuovo” was realized in the early 20th century and worked until the in ’60. The studied tunnel has a total length of 1229 m and, from geological point of view, it is located in the carbonate complex of the Maddalena Mountains and is characterized by the presence of stratified and fractured carbonate rocks. In proximity of this structure, there is also an important karstic cave (Castel di Lepre) already subject to geophysical measurements realized in the past [1]. The presence of a tunnel offers an advantageous perspective to monitor the aquifer improving the knowledge of the fluid circulation in a carbonate rock formation [2].

However, no engineering and geotechnical information about the realization of the construction and the geological setting of the area are available. In order to characterize, from an engineering point of view, the correlation between the hydrogeological formation and the engineering structure, several geophysical surveys, based on electric and electromagnetic acquisitions, were carried out along the gallery. The results obtained show the potentialities of the geophysical methods for monitoring and characterizing engineering structures also providing useful and detailed information for the identification of shallower geological structures in the first meters surrounding the tunnel. 

 

 

 

References 

[1] E. Rizzo, M. Guerriero, E. Gueguen, L. Capozzoli, G. De Martino and F. Perciante, Cave-surface Electrical Resistivity Tomography in “Castello di Lepre” Karst System (Marsico Nuovo, Southern Italy),  Monitoring and Characterization of the Shallow Subsurface I, EAGE 2017, DOI: 10.3997/2214-4609.201702078; 

[2] M. Guerriero, L. Capozzoli, G. De Martino, V. Giampaolo, E. Rizzo, F. Canora and F. Sdao, Geophysical techniques for monitoring carbonate karstic rocks (2019), Italian Journal of Engineering Geology and Environment, DOI: 10.4408/IJEGE.2019-01.S-10; Project: Landslide Risk Assessment along roads (LaRIS), Special Issue 1 (2019) Sapienza Università Editrice. 

How to cite: De Martino, G., Capozzoli, L., Giampaolo, V., and Rizzo, E.: GEOPHYSICAL MEASUREMENTS IN AN ABANDONED OLD RAILWAY TUNNEL (MARSICO NUOVO, Italy) , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7448, https://doi.org/10.5194/egusphere-egu2020-7448, 2020.

EGU2020-7582 | Displays | GI5.2

Development of iFTEM fixed-wing time-domain airborne electromagnetic instrument

Fang Ben, Junfeng Li, Wei Huang, Junjie Liu, Shan Wu, Lei Liu, Zhanhong Cao, and Hao Wang

    The fixed-wing time-domain airborne electromagnetic system transmits low-frequency electromagnetic pulse waves with large magnetic moments, receives weak secondary response electromagnetic field signals generated by the underground medium. It can realize deep depth airborne electromagnetic exploration. After 10 years of research and development, the Institute of Geophysical and Geochemical Exploration of the Chinese Academy of Geological Sciences successfully developed the first-generation fixed-wing time-domain airborne electromagnetic system of China in 2016——iFTEM. The peak transmit current is 600A, and the peak magnetic moment is 5.0 × 105Am2. The exploration depth is 350m. Test flights measurement were taken in 2016. Based on the first-generation iFTEM system, we upgraded the system. The new transmitter has a peak transmit current of more than 1000A and a peak magnetic moment of more than 1,000,000Am2. It has multi-wave transmit capability. The static noise of the three-component induction coil receiving sensor is better than 0.1nT/√Hz@1kHz. We are developing a time-domain airborne electromagnetic data processing software platform, which includes the data organization, denoising and correction software modules. This paper mainly introduces the development of China's first fixed-wing time-domain airborne electromagnetic instrument. This paper is financially supported by National Key R&D Program of China (2017YFC0601900) and CGS Research Fund (JYYWF20180103).

How to cite: Ben, F., Li, J., Huang, W., Liu, J., Wu, S., Liu, L., Cao, Z., and Wang, H.: Development of iFTEM fixed-wing time-domain airborne electromagnetic instrument, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7582, https://doi.org/10.5194/egusphere-egu2020-7582, 2020.

EGU2020-18736 | Displays | GI5.2

THz imaging in the frame of the Archaeological Urban Park of Naples project

Ilaria Catapano, Carlo Noviello, and Giovanni Ludeno

The Archaeological Urban Park of Naples (PAUN) project aims at addressing the need of analytical information relating to cultural heritage with modalities that encourage innovation systems of protection and enhancement. In this frame, one of the specific goals is the testing of multiple non-invasive or only minimally invasive investigation techniques, aimed at identifying a permanent diagnostic system calibrated to the specific context of the Urban Archaeological Park of Piazza Municipio, Napoli, Italy.

Among the electromagnetic sensing technologies, those exploiting Terahertz waves (1THz = 1012 Hz) are the newest among the imaging techniques, which offers the attractive chance of characterizing the inner features of manmade objects with a sub-millimeter spatial resolution in a non-invasive way while assuring negligible long-term risks to the molecular stability of the exposed objects.

This possibility together with the recent development of compact, transportable and easily reconfigurable devices make THz imaging a more and more widespread considered investigation tool in the frame of cultural heritage. THz imaging allows, indeed, the gaining of information useful to improve knowledge about the design technique adopted by the artist and to detect possible damages affecting the conservation state of precious artworks [1].

In the frame of PAUN project, THz imaging is considered as part of the sensor network, which is dedicated to the material characterization and supports the conservation and use of the assets of the Urban Archaeological Park of Piazza Municipio. Specifically, THz imaging is adopted to analyze ancient decorated mortar specimens and gather information on their stratigraphy. At this regard, it is worth pointing out that the effectiveness of THz imaging, i.e. the capability of obtaining high resolution images of the object under test, is dependent not only on the performances of the hardware technology but also on the data processing approaches. Herein, we consider the time domain Z-Omega Fiber-Coupled Terahertz Time Domain (FICO) system, which is available at IREA-CNR, and a data processing chain specifically designed to improve the discrimination of different material layers and to reconstruct the inner features characterizing the investigated artworks [2].

 

[1] Fukunaga, THz Technology Applied to Cultural Heritage in Practice, Cultural Heritage Science, Springer.

[2] Catapano, I., Soldovieri, F. A Data Processing Chain for Terahertz Imaging and Its Use in Artwork Diagnostics. J Infrared Milli Terahz Waves 38, 518–530 (2017).

 

Acknowledge: Authors would like to thank the PAUN project “Archaeological Urban Park of Naples” by which the present work has been financed.

 

How to cite: Catapano, I., Noviello, C., and Ludeno, G.: THz imaging in the frame of the Archaeological Urban Park of Naples project , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18736, https://doi.org/10.5194/egusphere-egu2020-18736, 2020.

EGU2020-19538 | Displays | GI5.2

Drone based visual inspections, Infrared Thermography investigations and GPR surveys of the Roman masonry bridge Ponte Lucano, Tivoli, Italy

Giovanni Ludeno, Chiara Biscarini, Ilaria Catapano, Nicola Cavalagli, Francesco Ascanio Pepe, and Filippo Ubertini

The objective of this study is to evaluate the cooperative use of non-destructive contactless diagnostic technologies as a tool to enhance the amount of information useful to assess historical assets’ structural and material degradation. The case study regards the Ponte Lucano structure in Tivoli (Italy) a Roman bridge located along the Aniene River, the largest tributary of the Tiber. It can be considered as an emblematic iconic structure in synthetizing the needs of structural consolidation and monument conservation. The bridge is, indeed, affected by hydraulic risk due to the floods of Aniene river.

Unmanned aerial (UAV) 3D photogrammetric surveys were carried out to perform visual inspections accounting for those bridge portions that are difficult to be reached directly. Hence, infrared thermography (IRT) and ground penetrating radar (GPR) surveys were considered as complementary technologies useful to obtain information about surface and subsurface structural features [1], [2]. The IRT analysis w characterized the thermal profile of the bridge and detected its most humid parts. The GPR investigations were performed to improve knowledge of the bridge subsurface structure.

The results of the analysis demonstrate that, the integration of mentioned diagnostic tools, provide information about the degradation state of the stones and its causes, as well as regarding the evolution of the structure from its construction up to the present configurations. In particular, UAV 3D photogrammetry allowed a very detailed digital map of the bridge, covering almost every part of the structure and revealing precious informations, among which chromatic properties and size characteristics of the bridge areas which are not directly accessible by a human operator. IRT results corroborated the hypothesis that the present degradation condition of the Ponte Lucano is mainly a result of the water retention within its materials. GPR images, provided information about the internal stratification of the materials of the bridge and allowed the localization of two buried arch structures, allegedly located in the northern bank and at the Plautii Mausoleum, whose presence confirms the historical-bibliographical hypothesis about the bridge building processes.

[1] Meola, C. Infrared thermography of masonry structures. Infrared Physics and Technology 2007; 49(3 SPEC. ISS.), 228-233.

[2] Daniels D.J. Ground Penetrating Radar. In IEE Radar, Sonar and Navigation Series 15; IEE: London, UK, 2004.

How to cite: Ludeno, G., Biscarini, C., Catapano, I., Cavalagli, N., Pepe, F. A., and Ubertini, F.: Drone based visual inspections, Infrared Thermography investigations and GPR surveys of the Roman masonry bridge Ponte Lucano, Tivoli, Italy, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19538, https://doi.org/10.5194/egusphere-egu2020-19538, 2020.

EGU2020-21804 | Displays | GI5.2

Environmental influences on historical monuments: a multi-analytical characterization of degradation materials

Joao Pedro Veiga, Fernanda Carvalho, Hugo Aguas, Giampiero Montesperelli, Elissavet Kavoulaki, Elpida Politaki, Angeliki Psaroudaki, Aggelos Philippidis, Kristalia Melessanaki, Panayiotis Siozos, Paraskevi Pouli, Antonella Curulli, and Giuseppina Padeletti

The Minoan Palace of Knossos and the Venetian coastal fortress “Rocca a mare” (Koules), located in Heraklion, Crete, Greece, are two important monuments for the history of mankind particularly vulnerable to environmental conditions, since they are located in an island subjected to strong variations in humidity and, as in the case of the Venetian fortress, in direct contact with sea water. In this type of surrounding environment, the formation of salt efflorescence as well as various other soluble salts crusts is a common situation. They occur according to the existing solubilization and crystallization conditions and can happen either in exterior or interior areas of the monuments. Their presence may stimulate further degradation, either due to the chemical dissolution of the substrate materials or due to the mechanical actions created by the formation of crystals, which may result in the decay of the substrate.

A set of samples from both monuments were analysed using various laboratory (ex-situ) analytical methods such as optical microscopy (OM), X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), Raman spectroscopy and Laser-Induced Breakdown Spectroscopy (LIBS). In-situ measurements using portable Raman and LIBS instruments were also performed. The comparative results from ex-situ analysis and in-situ measurements will be presented with emphasis to the chemical composition of the crusts and their origin. Results indicate that observed stalactites and salt efflorescence are directly related to the type of supporting material and the conditions of the surrounding environment. In general, the formation of crusts and salts are due to processes of alteration of the supporting material while the high impact of sea salt on the formation of the efflorescence at the Venetian coastal fortress was also confirmed.

 

[1] This work was supported by the European Union’s Framework Programme for Research and Innovation HORIZON 2020 under Grant Agreement 700395 project HERACLES.

Acknowledgment to the Portuguese Foundation for Science and Technology (FCT) UID/EAT/00729/2013 and EAT/00729-3 by FEDER funds through the COMPETE 2020 Programme and National Funds through FCT—Portuguese Foundation for Science and Technology under the project number POCI-01-0145-FEDER-007688, Reference UID/CTM/50025/2013 NOVA.ID.FCT, and the PhD Scholarship SFRH/BD/145308/2019.

How to cite: Veiga, J. P., Carvalho, F., Aguas, H., Montesperelli, G., Kavoulaki, E., Politaki, E., Psaroudaki, A., Philippidis, A., Melessanaki, K., Siozos, P., Pouli, P., Curulli, A., and Padeletti, G.: Environmental influences on historical monuments: a multi-analytical characterization of degradation materials, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21804, https://doi.org/10.5194/egusphere-egu2020-21804, 2020.

The Monte Abatone Necorpolis is one of the main important necropolis of Cerveteri, located 60 km north of Rome (Latium, Italy). In this area, several tombs have been discovered and excavated from the 1800, though still many remain hidden underneath the subsurface.

In the last two years, geophysical surveys have been carried out to investigate the unexplored portions of the ancient Etruscan Necropolis, to provide a complete mapping of the position of the tombs. Ground Penetrating Radar and the Magnetometric methods have been used during 2018 to investigate few parts of the Necropolis. During 2019 (July and September) GPR system SIR 3000 (GSSI), equipped with a 400 MHz antenna with constant offset, SIR4000 (GSSI) equipped with a dual frequency antenna with 300/800 MHz and the 3D Radar Geoscope multichannel stepped frequency system were employed to survey 5 hectares where the presence of tombs was hypothesized from previous archaeological studies.

All the GPR profiles were processed with GPR-SLICE v7.0 Ground Penetrating Radar Imaging Software (Goodman 2017). The basic radargram signal processing steps included: post processing pulse regaining; DC drift removal; data resampling; band pass filtering; background filter and migration. With the aim of obtaining a planimetric vision of all possible anomalous bodies, the time-slice representation technique was applied using all processed profiles showing anomalous sources up to a depth of about 2.5 m.

The preliminary obtained results clearly show the presence of a network of strong circular features, linked with the buried structural elements of the searched tombs.

Together with archaeologists, these anomalies, have been interpreted to have a better understanding of the archaeological definition of these features and to enhance the knowledge of the necropolis layout and mapping; after the geophysical surveys, excavations have been conducted, which brought to light few of the investigated structures.

 

References

Campana S., Piro S., 2009. Seeing the Unseen. Geophysics and Landscape Archaeology. Campana & Piro Editors. CRC Press, Taylor & Francis Group. Oxon UK, ISBN 978-0-415-44721-8.

Goodman, D., Piro, S., 2013. GPR Remote sensing in Archaeology, Springer: Berlin.

Piro S., Papale E., Zamuner D., Kuculdemirci M., 2018. Multimethodological approach to investigate urban and suburban archaeological sites. In “Innovation in Near Surface Geophysics. Instrumentation, application and data processing methods.”, Persico R., Piro S., Linford N., Ed.s. pp. 461 – 504, ISBN: 978-0-12-812429-1, pp.1-505, Elsevier.

How to cite: Piro, S. and Malandruccolo, B.: High resolution GPR investigations employing single and multichannel systems in the Necropolis of Monte Abatone, Cerveteri (Roma, Italy)., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1883, https://doi.org/10.5194/egusphere-egu2020-1883, 2020.

EGU2020-21569 | Displays | GI5.2

Investigation of the characteristics of the Soil by means of TDR probes: preliminary work and future perspectives

Lourdes Farrugia, Iman Farhat, Raffaele Persico, and Charles Sammut

In this contribution, we propose a novel technique for the measurement of electromagnetic characteristics of soil by means of a transmission line probe. This approach involves placing a sample of material under test (MUT) inside a transmission line terminated by the short circuit from one end and excited by a VNA at the input end. Unlike the well-known transmission line technique, which requires a two-port connection to a Vector Network Analyser (VNA)  to acquire the scattering parameters (S11 and S21), this method relies only on the measured S11 parameter which is then converted into the complex permittivity (dielectric properties) of the soil. Validation of the proposed transmission line model calculations was compared with numerical simulation data obtained with the CST Studio® software and measurement setup of the coax-line. The comparison shows that the dielectric and magnetic properties of a material may be precisely determined with the proposed technique. However, further studies need to be carried to extend this technique, such that a sample can be placed in contact with the probe rather than embedded in it.

How to cite: Farrugia, L., Farhat, I., Persico, R., and Sammut, C.: Investigation of the characteristics of the Soil by means of TDR probes: preliminary work and future perspectives, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21569, https://doi.org/10.5194/egusphere-egu2020-21569, 2020.

GI5.5 – Advances in 3D earth-surface modelling: data acquisition, analysis and visualization.

EGU2020-7725 | Displays | GI5.5

Realistic estimates of floc porosity based on high resolution 3D X-Ray microtomography

Simon Carr, Thomas Lawrence, Kate Spencer, Andrew Manning, Jonathan Wheatland, and Andrew Bushby

Suspended particulate matter (SPM) plays a fundamental role in the impact and eventual fate of sediment, pollutants, pathogens, nutrients and manufactured nano-materials in aquatic environments. SPM usually exists in aquatic systems as flocs; complex, fragile and loosely-bound aggregates of fine sediment particles, bacteria, organic matter and fluid-filled pore space. Floc settling velocity is widely considered to be the most important dynamic characteristic that determines SPM fate and transport, and is dependent on the size, shape, density, porosity, fractal dimension and composition of the flocs formed in suspension. Of these characteristics, floc density and porosity are thought to exert the greatest impact on settling velocity, yet neither parameter can currently be measured. As such, transport model parameters are typically estimated from Stokes’ Law, based on an assumption of a spherical shape for the floc. Due to a lack of available observational data, such assumptions cannot be validated and porosity is often omitted with flocs treated as essentially impermeable spherical entities, despite pores accounting for much of the defined ‘floc-space’ (often estimated to be > 90% within larger macro-flocs).

 

As part of a wider project exploring the 3D nature of floc structure and dynamics (NERC-3D Flocs), this study reports a first application of high-resolution 3D X-Ray microtomography on populations of flocs, offering a method that quantifies 3D floc porosity based on observation rather than assumption of floc structural properties. High resolution (3 µm voxel size) scans of both laboratory-generated and natural floc populations, from which sub-populations of different-sized micro- and macro-flocs (30 in each of 5 size categories for each floc population) are extracted. A data-processing workflow is presented which applies 3D morphological filters to systematically define a realistic expression of the total pore-space associated with individual flocs. Floc pore-space is further partitioned into isolated and effective pores, based on a 12 µm pore throat diameter threshold below which fluid flow is hydrodynamically minimal. Analysis of these realistic floc porosity data populations indicates that previous assumptions of floc porosity lack meaning in terms of settling dynamics. Substitution with meaningful, realistic floc porosity will have a significant impact on the prediction of floc settling velocity within SPM sediment transport models. 

How to cite: Carr, S., Lawrence, T., Spencer, K., Manning, A., Wheatland, J., and Bushby, A.: Realistic estimates of floc porosity based on high resolution 3D X-Ray microtomography, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7725, https://doi.org/10.5194/egusphere-egu2020-7725, 2020.

EGU2020-11673 | Displays | GI5.5

A New 3D Descriptor for Irregularly Shaped Suspended Sediment Aggregates

Jonathan Wheatland, Kate Spencer, Stuart Grieve, Chuan Gu, Simon Carr, Andrew Manning, Andrew Bushby, and Lorenzo Botto

Within coastal and estuarine environments suspended cohesive sediments that are often closely associated with carbon, nutrients, pathogens and pollutants form aggregates commonly known as ‘flocs’. Understanding the settling dynamics and eventual fate of flocculated sediment is therefore a major issue for the management of aquatic environments. Several factors have been reported to influence the hydrodynamic behaviour of flocs, including size, shape, density and porosity. Recent evidence suggests that of these shape exerts the greatest influence on settling rates. Yet means of characterising shape have been limited to easy to measure quantities such as fractal dimension and circularity measured in 2-dimensions (2D) that fail to capture the highly complex, irregular geometries of sediment flocs. However, recent improvements in sampling methods, 3D imaging capabilities and data processing software enable for the first time the characterisation of flocs based on their 3D morphology.

This study compares the morphologies of natural and artificial flocs generated under different environmental conditions. By employing a novel apparatus for the capture, immobilisation and handling of delicate floc samples, 3D X-ray micro-computed tomography (X-ray µCT) scans are successfully obtained and used to derive accurate volumetric reconstructions of tens of thousands of individual flocs. Using these datasets we compare different methods for describing shape, and test these for their ability to predict floc settling behaviours.

How to cite: Wheatland, J., Spencer, K., Grieve, S., Gu, C., Carr, S., Manning, A., Bushby, A., and Botto, L.: A New 3D Descriptor for Irregularly Shaped Suspended Sediment Aggregates, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11673, https://doi.org/10.5194/egusphere-egu2020-11673, 2020.

EGU2020-11970 | Displays | GI5.5 | Highlight

Unity game engine as a method of presentation of data collected from UAV

Daniel Janos, Justyna Ruchała, Edyta Puniach, and Paweł Ćwiąkała

Representatives of the scientific community collect and store huge amounts of spatial data resulting from years of their studies. However, there is a common problem of visualization methods of data which would be interesting to understand for a recipient from outside of the area as well as according to the current trends. In the modern day, many spheres of our life have been moved to the virtual reality and that is why representatives of areas such as industry, science, culture and art need to deal with the representation of the real world in a 3D reality.

 

This work is concerned with the current issue of visualization of spatial data collected by surveyors as well as representatives of many other areas. The proposed method of presentation of collected research data is not only low-cost at preparation but is also distinguished by its simplicity of implementation. Its functionality will be presented by using an example of the Agora area located in the Archaeological Park of Kato Paphos in Cyprus. The mentioned area was created in order to protect and promote the archaeological sites as well as the artefacts from the former epoch which have been found in the area. Such historic places are very often not fully available to see by visitors and that is why the documentation and visualization of them in 3D reality might be incredibly helpful. This kind of activity not only contributes to the popularization of archaeological research but also meets the expectations of a modern recipient who uses virtual reality more and more often in order to learn about new places. It is worth mentioning that the presented visualization of measurement data is a versatile method that is intended to be used in many different scientific and research areas.

 

From a technical point of view, the presented work guides a recipient through the complete process of development of an advanced animation in the environment used in the creation of 3D computer games – the game engine Unity. In the first part of the article the suitability of the data results obtained in digital photogrammetry as well as laser scanning was estimated for purposes of applying the presented method. The work also brings up the issues of limitation of free software and raises a question of methods allowing to meet the requirements with minimized loss of quality and accuracy of the data. The next step was to present the method of importing data (a mesh model and a high-resolution texture). Operating mechanism in Unity as well as a transfer of interactive visualization into the online browser Unity Connect were discussed in the further part of the article. It is worth mentioning that thanks to the FPP (First Person Perspective) technique the developed visualization allows a user to be transferred right into the centre of the archaeological sites where the admission for the third party is usually significantly restricted.

How to cite: Janos, D., Ruchała, J., Puniach, E., and Ćwiąkała, P.: Unity game engine as a method of presentation of data collected from UAV, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11970, https://doi.org/10.5194/egusphere-egu2020-11970, 2020.

EGU2020-12048 | Displays | GI5.5 | Highlight

Application of UAV in measurements of earth structure deformation

Agata Bochniarz, Anna Wójcik, Edyta Puniach, and Paweł Ćwiąkała

Unmanned Aerial Vehicles (UAV) are currently one of the most popular methods of colleting photogrammetric data. A short time of data acquisition and low costs are the key advantages of this solution, especially important during cyclical measurements of various types of objects.

The aim of this paper is to assess the possibility of using images obtained from UAV to determine the deformation of earth structures. The object of measurement was Krakus Mound located in Cracow (Poland). It is one of the oldest mounds in Cracow, preserved to this day. The history of this hill is unknown but it is assumed that the mound was built in stages. In 2013, the site was renovated.

As a part of the research, between 2015 and 2019, cyclic photogrammetric flights were carried out over Krakus Mound. For this purpose, DJI S900 aircraft equipped with a non-metric visible light camera Sony Alpha a6000 was used. The measurements were taken every year in spring and autumn. In total, 7 measurement sessions were performed, during which the coordinates of ground control points and check points were measured each time. As part of fieldwork, numerous comparative measurements were also carried out using other surveying instruments, such as GNSS receivers, total stations and terrestrial laser scanner.

This paper presents the results of research aimed at observing the geometry of the mound in 2015-2019. Low-altitude images obtained in combination with the Structure from Motion technique allowed to generate photogrammetric products to determine the deformation of the object. Generated UAV-derived point clouds and digital terrain models were used for the analyses. They were compared with reference data, i.e. photogrammetric products created on the basis of data obtaining during the first UAV flight and the results of total station and satellite measurements. This made it possible to determine the influence of the low vegetation on the results of measurements and to check whether the object is deforming. The research also included terrestrial laser scanning of the mound and usage of available LiDAR data to compare scanning data with low-altitude photogrammetric products. Numerous analyses allowed to create methodology of inventory measurements of earth structure covered with low vegetation using UAV-based photogrammetry. 

How to cite: Bochniarz, A., Wójcik, A., Puniach, E., and Ćwiąkała, P.: Application of UAV in measurements of earth structure deformation , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12048, https://doi.org/10.5194/egusphere-egu2020-12048, 2020.

EGU2020-16720 | Displays | GI5.5

Generation of 3D building model using different LoD

Wojciech Dziok, Aleksandra Jasińska, Edyta Puniach, and Paweł Ćwiąkała

            With the technological progress, the demand for a three-dimensional presentation of the world around us is growing. Currently, modelling of urban space in 3d based on presenting it as simple geometric solids is not able to satisfy the needs of the constantly growing market. There are also noticeable trends aimed at representing the real world as faithfully as possible in virtual space.

            The purpose of this work is to show the differences between the individual levels of detail (LoD) of the building facade model obtained using classic geodetic measurements as well as ground photogrammetry and UAV photogrammetry. For this purpose, pictures of the building facade were taken and its characteristic elements were measured so that the generated model was metric.

            Creating a vector model of the facade consisted in modelling individual blocks based on points obtained from the total station measurement. The model was generalized for individual levels of detail using fewer points to make it. Subsequently, vector models were textured by photos.

In addition, oblique facade photos were developed, and then a triangular mesh model was made from the dense point cloud generated on their basis. The model was analyzed for meeting the accuracy criteria of individual LoDs in order to determine whether the use of only photogrammetric data allows the generation of a suitably detailed spatial model.

The resulting models were compared with each other, thanks to which it is possible to verify whether the facade is symmetrical and how repeatable its architectural elements are. The outcome also enables the assessment of the accuracy with which the building elements should be measured in order to obtain a reliable model that meets the criteria of the assumed LoD level for the resulting product.

How to cite: Dziok, W., Jasińska, A., Puniach, E., and Ćwiąkała, P.: Generation of 3D building model using different LoD, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16720, https://doi.org/10.5194/egusphere-egu2020-16720, 2020.

EGU2020-18273 | Displays | GI5.5

Immersive Flooding Event Simulation for Climate Resilience Analysis

Yang Jiang, Joan Alza Santos, Chen Wang, and Leslie Mabon

Immersive Technology has been widely discussed in various applications; the development of this technology creates an experience which is not possible in our physical reality. The rapid development of computer software and hardware makes the 3D visualisation and simulation of real-world scenarios could be represented in much higher resolutions. Recent studies show that visualising natural disasters immersively could be beneficial to increase people’s awareness and prepare the public for future event. In a recent research project, we visualized and simulated a flooding event, Storm Frank, in 2015 and its damage to the local residence of a town called Ballater outside Aberdeen, UK on Virtual Reality form. To provide accurate simulation, topographic data and real-world environmental data such as weather, rainfalls, river level data etc., are applied and analysed in this project. This immersive experience provides significant opportunities for effective communication among all users. The project used 3D modelling and simulation of the flooding encompasses the development and exemplification of the model of the town and real scenario flooding event, retrieving data from various sources such as geographical data and environment data. The gamification of this application shows great potential to be used for public engagement event, policy making and educational purposes. 

How to cite: Jiang, Y., Alza Santos, J., Wang, C., and Mabon, L.: Immersive Flooding Event Simulation for Climate Resilience Analysis, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18273, https://doi.org/10.5194/egusphere-egu2020-18273, 2020.

EGU2020-20592 | Displays | GI5.5

Establishing a 3D model for the Rhine-Ruhr region based on the geology and property distribution.

Gabriela de los Angeles Gonzalez de Lucio, Martin Balcewicz, and Erik H. Saenger

The Rhine-Ruhr region is located in the state of North Rhine-Westphalia (NRW) in western Germany. Due to the transition from coal to low-carbon heat sources, potential locations in NRW must be explored regarding to their geothermal potential. The Bavarian area has shown for the last 20 years, that deep geothermal energy is both feasible and economical in Germany. Compared to the mentioned Molasse basin in south Germany, the geological setting is much more complex in the Rhine-Ruhr region. Based on a typical geothermal gradient of 30 °C/km, the optimal depth of a reservoir should be between 3000 m to 5000 m. In this depth, carbonate layers from Devonian times were identified in NRW. Due to the lack of accessibility, minor reservoir characterization was done, yet. Therefore, a geological model which reflects local lithological properties is essential for further geothermal projects. The model of the Rhine-Ruhr region is based on field surveys, top formations, geological sections and maps, respectively. The geometrical model is supplemented by rock properties, like density, porosity, and P- respectively S-wave velocities. These properties are derived from well logs, laboratory measurements and literature, transferring the derived properties to the grid require an analysis of upscaling techniques and distribution of such properties in the model. The result is a heterogeneous model representing the geological structure and rock property distribution of the Rhine-Ruhr region. Representative lithological units like Ruhrsandstone or interbedded coal, clay, and sandstone strata are also implemented as dominant fracture orientations. In this work we are considering several parameters to find a balance between the resolution of the model, property scaling and computational efficiency. One key aspect is that geological models are built with irregular grids while for our wave propagation simulations a regular and cartesian grid with equal grid spacing is required. Of course, such regular grids can be used for several modelling techniques and can be used as a basis for different studies. Overall goal is to evaluate local geological models to assess the feasibility of geothermal projects in the area.

How to cite: Gonzalez de Lucio, G. D. L. A., Balcewicz, M., and Saenger, E. H.: Establishing a 3D model for the Rhine-Ruhr region based on the geology and property distribution., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20592, https://doi.org/10.5194/egusphere-egu2020-20592, 2020.

EGU2020-22054 | Displays | GI5.5

Integrating acoustics and photogrammetry-based 3D point clouds for the generation of a continuous bathymetric model in coral reef environment.

Alessandra Savini, Fabio Marchese, Luca Fallati, Cesare Corselli, and Paolo Galli

Digital terrain model (DTM) reconstruction in coral reef environments through traditional mapping methods, using either singlebeam or multibeam echosounder systems, often presents difficulties in obtaining a continuous 3-dimensional representation, due to the complex topography and the considerable extension of very shallow areas (i.e. reef flat areas). The present-day most advanced techniques used to collect high-resolution elevation data both for land surface and the seafloor, in coral reef environments, include the use of satellite-derived bathymetry, LIDAR technology, Unmanned Aerial Vehicles coupled with photogrammetry and traditional bathymetric surveys. Data processing represents in all the cases a fundamental step for ensuring the accuracy and reliability of obtained measurements, especially for allowing a precise integration of all data sources into a continuous DTM. In our work, we present a tested methodological protocol for the generation of a continuous fine-scale digital terrain model (DTM) in coral reef environments. A portion of an atoll reef (Magoodhoo reef located in the Maldivian archipelago, the southern part of Faafu atoll) has been remotely mapped from the reef flat area to the connected and deeper lagoon environment, collecting elevation data by different sources according to the surveyed depths. In particular, we acquired acoustic depth measurements using a multibeam echosounder and 3D point clouds applying the Structure from Motion (SfM) technique to RGB images, collected using an Unmanned Aerial Vehicle (UAV). All obtained data were calibrated and validated with RTK-GNSS measurements and successfully integrated in order to generate a harmonized DTM for the surveyed sector of the Magoodhoo reef.

How to cite: Savini, A., Marchese, F., Fallati, L., Corselli, C., and Galli, P.: Integrating acoustics and photogrammetry-based 3D point clouds for the generation of a continuous bathymetric model in coral reef environment., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22054, https://doi.org/10.5194/egusphere-egu2020-22054, 2020.

GI5.7 – Multidisciplinary underground laboratories and test sites – what makes them tick?

EGU2020-22403 | Displays | GI5.7

Six Underground Laboratories (ULs) Participating in the Baltic Sea Underground Innovation Network

Mats Ohlsson, Jari Joutsenvaara, Marcus Laaksoharju, and Eija-Riitta Niinikoski

Baltic Sea Underground Innovation Network, BSUIN, consist of six participating Underground Laboratories (ULs) located in countries surrounding the Baltic Sea [http://bsuin.eu]. The BSUIN is a three-year project funded by the EU Interreg Baltic Sea Region Programme. 

The aim of the BSUIN project is that the participating ULs will find new or expand the current use of underground laboratories to enhance the power of innovation and regional development. The project focus on the characterisation of the geological and technical settings of the ULs, health and safety issues, and various aspects to build and support innovation and the formation of a permanent network of Underground Laboratories.

The BSUIN ULs consist of old mines or purpose-built underground facilities. The ULs are used for research concerning e.g. environmental, geoenergy, geotechnology, physics, material science and natural sciences. Education, events, tourism and farming is also activities hosted by ULs.

We will present the underground laboratories of the BSUIN network:

  • Äspö Hard Rock Laboratory, Oskarshamn, Sweden [http://www.skb.com/research-and-technology/laboratories/the-aspo-hard-rock-laboratory/],
  • Forschungs- und Lehrbergwerk - Research and Eduction Mine "Reiche Zeche", Freiberg, Germany [http://www.besucherbergwerk-freiberg.de/],
  • Callio Lab in Pyhäsalmi mine, Pyhäjärvi, Finland [calliolab.com/callio-lab],
  • KGHM S.A. mining company, Poland, together with their research organisation KGHM CUPRUM which proposes the construction of ULs located in one of the KGHM’s deep copper [http://www.cuprum.wroc.pl/],
  • The Low-Background underground laboratory of Khlopin Institute, St Petersburg, Russia [http://www.khlopin.ru/en/],
  • Ruskeala Marble quarry and Geopark in Sortavala, Karelia, Russia. [http://ruskeala.info/en].

How to cite: Ohlsson, M., Joutsenvaara, J., Laaksoharju, M., and Niinikoski, E.-R.: Six Underground Laboratories (ULs) Participating in the Baltic Sea Underground Innovation Network, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22403, https://doi.org/10.5194/egusphere-egu2020-22403, 2020.

EGU2020-20808 | Displays | GI5.7

The Gran Sasso National Laboratory

Matthias Laubenstein

In order to explore the highest energy scales that cannot be reached with accelerators, underground laboratories provide the low radioactive background environment necessary to search for extremely rare phenomena. Experiments range from the direct search for dark matter that constitutes the largest fraction of matter in the Universe, to the exploration of the properties of the neutrinos, the most elusive of the known particles and which might be particle and antiparticle at the same time, and to the investigation on why our universe contains only matter and almost no antimatter, and much more.

The Gran Sasso underground laboratory is one of the four Italian national laboratories run by the INFN (Istituto Nazionale di Fisica Nucleare). It is located under the Gran Sasso massif, in central Italy. To date it is one of the largest underground laboratories for astroparticle physics in the world and the most advanced in terms of complexity and completeness of its infrastructures. The scientific program at the Gran Sasso National Laboratory (Laboratori Nazionali del Gran Sasso, LNGS) is mainly focused on astroparticle, particle and nuclear physics. The laboratory presently hosts many experiments as well as R&D activities, including world-leading research in the fields of solar neutrinos, dark matter, neutrinoless double-beta decay and nuclear cross-section measurements of astrophysical interest. Other branches of sciences like earth science, biology and fundamental physics complement the activities carried out. The laboratory is operated as an international science facility and hosts experiments whose scientific merit is assessed by an international advisory Scientific Committee. A review of the main experiments carried out at LNGS will be given, together with the most recent and relevant scientific results achieved.

How to cite: Laubenstein, M.: The Gran Sasso National Laboratory, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20808, https://doi.org/10.5194/egusphere-egu2020-20808, 2020.

EGU2020-21709 | Displays | GI5.7

Helmholtz Innovation Lab 3D-Underground Seismic Lab

Katrin Jaksch and Rüdiger Giese

Since 20 years the GFZ (German Research Centre for Geosciences) operates in an underground lab in the research and education mine Reiche Zeche at Freiberg in eastern Germany. This underground lab is used as testing lab for newly developed geophysical equipment and methods for 3D seismics. Therefore, in the underground space several galleries and boreholes can be used for seismic exploration in 2D and 3D approaches and for testing and validation of seismic acquisition equipment.

Now, a Helmholtz Innovation Lab will be established at the GFZ in Potsdam. The Helmholtz Innovation Lab 3D-Underground Seismic Lab (3D-US Lab) is a place where scientific expertise and the needs of industry and its customers will meet together. By involving partners from mining and tunnelling in joint development projects on a long-term basis and transferring approaches from research into commercially successful applications a sustainable 3D-US Lab will be established.

The 3D-US Lab bundles the seismic methods developed at the GFZ in a single technology platform, standardizes and modularizes them. It combines the technological and methodological developments in tunnel and borehole seismics for 3D seismic exploration of underground structures. The technology platform and the GFZ underground laboratory in Freiberg are of great interest for various partners from mining and tunnelling. In the long term the Helmholtz Innovation Lab aims to establish 3D underground seismics as a key technology for the effective and safe construction and use of underground buildings.

How to cite: Jaksch, K. and Giese, R.: Helmholtz Innovation Lab 3D-Underground Seismic Lab, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21709, https://doi.org/10.5194/egusphere-egu2020-21709, 2020.

Addressing future energy challenges and new zero carbon targets will require increasing use of the subsurface. Utilising the subsurface with public consent requires impartial, independent and open data to adequately evaluate potential risks. De-risking of the subsurface is dependent on new standardised data, highly characterised locations and readily available subsurface experimental facilities to deliver the innovation needed.

To address this NERC and UKRI have provided funding to BGS to construct geoscience observatories at two UK locations to deliver new long-term research. Such observatories require the geology to be characterised in detail, to provide a database to baseline new hypothesis-led experimental science.

The observatories will benefit from a pre-existing database of high quality geoscience data to increase over the operational lifetime. Characterisation of each facility site has involved the integration of baseline monitoring, regional borehole data and where available 2D and 3D seismic which are beyond the limits of research budgets.  Once completed each observatory site will comprise a wide range of publicly available data including: fully-cored and characterised boreholes, facilities to baseline the regional groundwater environment, a set of new downhole sensors for time-series monitoring of geophysical and geological parameters served in real-time via the internet to anyone.

The construction phase of the UK Geoenergy Observatories (UKGEOs) Cheshire Energy Research Facility Site will begin construction in summer 2020. The site has been chosen at an accessible location in a sequence of scientifically and significant Triassic to Carboniferous strata. This sequence is typical of the sediments under much of northern England, included areas which have been explored for oil hydrocarbons. Up to 50 boreholes between 50–1200m depth will be drilled, with a combined length of up to 8000m, including 3000m of core and geophysical logging, including resistivity borehole imaging.

The boreholes will be split in arrays to characterise the region including: baseline groundwater, quantify the baseline seismicity down to near globally unique resolution of -0.6 to -1.0 M and characterising a volume of rock so it can then be dynamically parameterised with properties. This will become a default locations for synthesis and testing of new solutions to energy by becoming the basis for an experimental faculty where natural and anthropogenic perturbations can be undertaken and monitored.

UKGEOs will create a long-term experimental facility open for all scientists for experiments and testing of new subsurface technology. All materials recovered will be available for sampling with derived data and published research made available to create an ever-growing archive of data to facilitate future understanding.  

An immediate priority research question is the capacity for faults to act as conduits or barriers to subsurface fluid flow. This is a major concern to the public around hydrocarbon developments but is of critical relevance to any development of deep geothermal heat, subsurface storage of energy and gas or Carbon Capture and Storage. CERFS will provide the facilities to deliver such research and new insights.

 

How to cite: Kingdon, A., Spence, M., and Fellgett, M.: Cheshire Energy Research Facility Site (CERFS): A new experimental observatory location for geoscience energy research. , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11769, https://doi.org/10.5194/egusphere-egu2020-11769, 2020.

EGU2020-22309 | Displays | GI5.7

Multi-Dimensional Information Modelling Method for Underground Tunnel Spaces

Rauno Heikkilä, Jorma Hopia, and Anssi Rauhala

A study of Multi-Dimensional information modelling of underground tunnel spaces is introduced. As a reference model an international  standard of Building Information Modelling (BIM) supported by Building Smart is used. Specific Finnish guidelines for infrastructures including tunnels are used. As experimental case underground Pyhäsalmi Mine on North Finland was used. Three selected tunnel at level of 660 meter were used. The tunnels were measured using advanced 3D laser scanning technologies as well as photogrammetric imaging. Different examples of tunnel information models were created and analysed. Recommendations for future work how to develop tunnel information modelling towards more and more information rich  Multi-Dimensional information models are suggested.

How to cite: Heikkilä, R., Hopia, J., and Rauhala, A.: Multi-Dimensional Information Modelling Method for Underground Tunnel Spaces, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22309, https://doi.org/10.5194/egusphere-egu2020-22309, 2020.

EGU2020-4437 | Displays | GI5.7

Conceptual design of underground laboratory under dynamic load condition in deep copper mine

Krzysztof Fulawka, Marcin Szumny, Witold Pytel, and Piotr Mertuszka

Underground laboratories, due to their unique location, are facilities with high research and educational potential. Development of old mine chambers or setting up of new mining panels designed strictly for research and educational purpose may contribute to the development of new mining technologies. One of the initiatives aimed to enhance of the underground space usage in Europe is BSUIN project conducted in the framework of INTERREG Baltic Sea Region program. At the moment there is only one underground laboratory designed fully for research and development purposes i.e. Experimental Mine Barbara lead by Central Mining Institute of Poland. But still, there are several dozen active underground mines working in Poland. Unfortunately, the large scale of the mined-out area contributes to the generation of relatively high seismicity around mining regions. Due to safety reasons management of Polish underground mines in most cases do not allow to build such a facility like underground laboratories in close vicinity of active mining works.

Within this paper, the prototype of an underground laboratory affected by additional seismic load was prepared in condition of Polish underground copper mine. Changes in total displacement and stresses around newly created chambers with use of FEM-based numerical modelling were determined. In result possibility of setting up of underground facility under dynamic load condition was determined.

How to cite: Fulawka, K., Szumny, M., Pytel, W., and Mertuszka, P.: Conceptual design of underground laboratory under dynamic load condition in deep copper mine, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4437, https://doi.org/10.5194/egusphere-egu2020-4437, 2020.

EGU2020-2980 | Displays | GI5.7

Characteristics of natural radiation background at the Research and Education mine Reiche Zeche (Germany) performed within the BSUIN project.

Katarzyna Szkliniarz, Kinga Polaczek-Grelik, Agata Walencik-Łata, Jan Kisiel, Toni Mueller, Falk Schreiter, and Robert Hildebrandt

The Reiche Zeche mine is one, out of 6 Underground Laboratories (ULs) participating in the BSUIN (Baltic Sea Underground Innovation Network) project. The main goal of BSUIN is to improve the utilisation of Underground laboratories operating in the Baltic Sea Region by creating an umbrella organisation, an association, to represent the underground locations. To improve the utilisation the Uls, the sites have been characterized to understand the possibilities of the sites. Of of the studied characteristics is natural background radiation. The Reiche Zeche mine is located at a depth of 150 m (410 m w.e.) in the eastern part of the Erzgebirge Mountains, Germany. The measurements of natural background radiation (NBR) were performed: (1) in-situ by using portable HPGe semiconductor spectrometer and RAD7 electronic radon detector, and (2) in the laboratory, where the concentration of radioisotopes in water and rock samples was determined. The laboratory measurements were done in the Institute of Physics, University of Silesia (Poland) by using a liquid scintillation α/β counter (LSC), gamma-ray spectrometry and α-particle spectrometry. The obtained results of natural radioactivity in Reiche Zeche (BSUIN UL) will be presented.

How to cite: Szkliniarz, K., Polaczek-Grelik, K., Walencik-Łata, A., Kisiel, J., Mueller, T., Schreiter, F., and Hildebrandt, R.: Characteristics of natural radiation background at the Research and Education mine Reiche Zeche (Germany) performed within the BSUIN project., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2980, https://doi.org/10.5194/egusphere-egu2020-2980, 2020.

EGU2020-20255 | Displays | GI5.7 | Highlight

Global network of underground research – Literature metadata analysis by Geographic Information Systems (GIS)

Ossi Kotavaara, Jari Joutsenvaara, Eija-Riitta Niinikoski, Pertti Martinmäki, and Ursula Heinikoski

Globally there are various underground facilities or laboratories, which are commonly located in active or closed mines, in tunnel systems or they are built for this specific purpose. There are also a vast number of study groups and researches within several disciplines utilising resources of these facilities. The Baltic Sea Underground Innovation Network (BSUIN) develops six such facilities, all having unique characteristics and operational settings. In developing underground laboratories, understanding characteristics, needs and accessibility of research communities applying these facilities is crucial. Aim of this study is to product new knowledge in this field, by analysing research published by this community. Geographic information systems (GIS) is applied to scrutinise the metadata of scientific literature databases. There is a great deal of published research having connection to underground facilities. For example, between years 2009-2018, Scopus database covers over 13,000 articles by over 40,000 authors. Preliminary analysis indicates that a wide variety of disciplines, such as engineering, earth and planet sciences, environmental sciences, physics and astronomy, as well as energy, material, computer and social sciences, are active within underground themes. In the analysis, publication specific data are compiled from literature databases, research units located globally by geocoding and data is organised for geographic and temporal analysis. By discipline information and indexed research fields and themes, patterns of global research trends within underground studies are explored. Results will indicate how distribution of study fields is organised, visualise the strength and activity of different disciplines and show the key temporal elements in development of research. This data enables also to extend the analysis to cover also the networked characteristics of research and researchers within underground laboratories.

How to cite: Kotavaara, O., Joutsenvaara, J., Niinikoski, E.-R., Martinmäki, P., and Heinikoski, U.: Global network of underground research – Literature metadata analysis by Geographic Information Systems (GIS), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20255, https://doi.org/10.5194/egusphere-egu2020-20255, 2020.

EGU2020-1451 | Displays | GI5.7 | Highlight

Developing Business Models for the Underground Labs

Päivi Aro and Helena Ahola

DEVELOPING BUSINESS MODELS FOR THE UNDERGROUND LABS 

The purpose of this case study is to describe the process of developing business models for the underground labs (ULs) and their network in a Baltic Sea Interreg project (BSUIN). The RQs are the following:

  • What kind of business models the ULs in the project have?
  • How could their business models be developed by focusing on specific customer segments and services and their value propositions?
  • What kind of business model(s) could serve best the network of ULs?

Professional services, such as ULs also offer, can be characterized by high labour content, high customization and high customer contact. The distinguishing feature of these services is also their knowledge-intensive nature. Business model describes the logic of how a company intends to make money.  Business Model Canvas is a useful tool for describing, analyzing and designing business models. At the core in the business model is Value Proposition. The value proposition describes the benefits customers can expect from the services and products.

Service Design was used as an approach in the project. It is a mindset, a process, a toolset, a cross-disciplinary language and a human-centred management approach. Data was gathered by facilitating Service Design workshops and analyzed by qualitative methods. The research process consisted of three phases: 1) describing and analyzing the existing business models of the ULs 2) developing business models of the ULs focusing on specific customer segments and services and their value propositions, and 3) developing business models for the network of the ULs.

In the Exploration workshops the business models of the ULs were described and analyzed. It can be concluded that paying customer segments are few in number, and fixed costs are significant. Each UL is unique having specific know-how, expertise and infrastructure. 

In Creation workshops the focus was on specific customer segments and services and their value propositions. The outcomes of the workshops were promising and recommendations for the ULs were made. ULs should look for new customer segments and create new services and value propositions. In addition, they should create and describe business models for the chosen customer segments and services.

In Reflection workshops business models for the network of the ULs were developed. The focus was particularly on core, supporting and additional services of the ULs. The core (essential) services are research infrastructure, underground infrastructure, site characterization and wide expertise for underground projects. A generic business model for the network was described based on the data, results, analyses and feedback of all the previous workshops.

It is challenging to develop business models for the ULs because they have not been business oriented. Every UL is unique, and the expertise is related to underground sciences. Business orientation would offer them an opportunity to boost underground scientific research which is the key element in the business model.

How to cite: Aro, P. and Ahola, H.: Developing Business Models for the Underground Labs, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1451, https://doi.org/10.5194/egusphere-egu2020-1451, 2020.

EGU2020-21767 | Displays | GI5.7

Innovation Management of BSUIN Underground Laboratories

Rüdiger Giese and Katrin Jaksch

The Baltic Sea Underground Innovation Network BSUIN is a European research project funded by Interreg Baltic Sea Region. The BSUIN network consists of six underground laboratories in Finland, Sweden, Russia, Poland and Germany with associated business and research partners. Each of the underground laboratories is unique in its geology, underground space and use. The BSUIN aims to build up a platform for innovative research and business concepts for the use of underground infrastructures and also especially for applications after completion of mining activities.

For an innovation management it is important to identify research and application fields in underground labs for the present but also research areas of interest in the future. Also it is significant to define the relevant research fields, which are more likely to result in innovations and business applications.

Within BSUIN an innovation platform concept will be established as a guideline for innovation management and support for the innovation processes. For that purpose we questioned aspects of the use of underground labs for users from several kind of customers and users from research and business of small and medium-sized enterprises.

Here we present an overview of the evaluation of the questionnaire. What are the main aspects which are important for the use of underground labs for research and innovation and especially for business activities? Within BSUIN a concept of an innovation platform concept will be integrated in the BSUIN web based tool. This will allow to apply innovation keywords to site-specific research activities in each BSUIN mine.

How to cite: Giese, R. and Jaksch, K.: Innovation Management of BSUIN Underground Laboratories, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21767, https://doi.org/10.5194/egusphere-egu2020-21767, 2020.

EGU2020-8989 | Displays | GI5.7

Research and Education Mine Reiche Zeche in Freiberg, Germany

Toni Mueller, Helmut Mischo, Vera Lay, and Stefan Buske

The Reiche Zeche mine is a unique location for research and education. Since 1919, the former ore mine is used for educating and training of miners, engineers and mine surveyors by the TU Bergakademie Freiberg. Drifts and tunnels of the mine stretch over several kilometres at depths down to 230 m. Today, the Reiche Zeche mine plays a major role in mining research and related activities including various research institutes and industrial partners. Several underground test facilities and laboratories are in use and important in university education. A variety of local (15 institutes of TU Bergakademie Freiberg) and external partners (30 from 26 countries) are actively shaping research and education in the mine. Within the framework of the Baltic Sea Underground Innovation Network (BSUIN http://bsuin.eu), we aim at forming an efficient platform for future, innovative research and business activities in underground laboratories.

How to cite: Mueller, T., Mischo, H., Lay, V., and Buske, S.: Research and Education Mine Reiche Zeche in Freiberg, Germany, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8989, https://doi.org/10.5194/egusphere-egu2020-8989, 2020.

EGU2020-22053 | Displays | GI5.7

Ruskeala underground laboratory for the study of natural waters (Karelia, Russia)
not presented

Galina Borodulina

Ruskeala underground laboratory was organized jointly by the Karelian Research Center of the Russian Academy of Sciences (KarRC RAS) and Kolmas Karelia company as an experimental innovative facility for the study of underground spaces. KarRC RAS is a partner in the Baltic Sea Underground Innovation Network (BSUIN) project of the Interreg Baltic Sea Region Programme. Ruskeala quarries can act as a showcase of the transformation of the chemical composition of groundwater formed in Proterozoic calcareous rocks of the Fennoscandian Shield and exposed by open mining. Drillholes reveal weakly alkaline fresh (0.4 g/l) bicarbonate calcium-magnesium groundwater, which, when discharged in quarries, loses dissolved gases (CO2, He, Rn), becomes more alkaline and fresher due to atmospheric precipitation. Since the biota in the man-made reservoirs is poor, nitrates, as the final product of the transformation of nitrogen compounds brought in by surface runoff, can accumulate in the quarry water. The mine network provides a unique opportunity for studying the hydrodynamics and geochemistry of groundwater and its interaction with surface waters.

The study was supported by BSUIN project of the Interreg Baltic Sea Region Programme

How to cite: Borodulina, G.: Ruskeala underground laboratory for the study of natural waters (Karelia, Russia), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22053, https://doi.org/10.5194/egusphere-egu2020-22053, 2020.

EGU2020-2891 * | Displays | GI5.7 | Highlight

Working environment: requirements and restrictions at Underground laboratories

Andrus Paat and Veiko Karu

The Underground laboratories (Uls) due to their unique conditions can be used in many ways - as machinery test site by industrial equipment providers, for scientific and technical equipment testing, as test site for various experiments for instance in particle and nuclear physics, for food production, for safety personnel trainings, for data storage purposes etc. In order to use underground spaces for various purposes, you have to know what underground working conditions are. Depending on location, depth, and other characteristics the working conditions and requirements in every underground facility are different.

We present an overview of the underground working environment in six different Uls. Named Uls locates in different EU countries and have different national regulations and requirements. We conducted a common standard of underground working environment what acts as the minimum level on which the working environment must meet. We mapped working environment conditions in such topics as ownership and regulation, air and water quality, safety and monitoring in ULs, lighting requirements, noise, vibration and radiation measurements, including risks and monitoring. The results are based on held questionnaire and data collection tour, which was carried out among six Uls.

Additionally, we will highlight the best practices and experiences that Uls have implemented in order to improve their working conditions. These best practices are usually more than the national laws and regulations have requested. The collected practices will help to set new higher standards of the working environment for the other Uls to aim at. The best practices are based on held questionnaire and data collection tour, which was carried out among in six Uls. By sharing the best practices among the Uls will lead to knowledge transfer and implementation of better working conditions where new practices can be applied.

The minimum working environment conditions and the best practices are part of the Baltic Sea Underground Innovation Network, BSUIN, project, which is funded by the Interreg Baltic Sea Region Programme

How to cite: Paat, A. and Karu, V.: Working environment: requirements and restrictions at Underground laboratories, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2891, https://doi.org/10.5194/egusphere-egu2020-2891, 2020.

EGU2020-20188 | Displays | GI5.7

Safety issues when using a museums in unused mining workings

Andrei Ivanov, Kirill Shekov, Vitali Shekov, Krzysztof Fuławka, and Witold Pytel

The underground space, which is not used for mining purposes, now serves more like a room for storing various goods, for organizing the production of goods, as mining museums, etc.

Using such space creates some dualism in its maintenance. On the one hand, it is simply an underground space, used as a storage, on the other hand the characteristics of this space are completely dependent on the natural conditions and properties of the rocks surrounding the mining workings. This is especially true for mining space used as mining museums, where it is unacceptable to cover mining workings walls with solid concrete support that will simply destroy the authenticity of the object. Whether it is necessary to have a mining engineer in the staff of such a museum?

The authors hold to the concept that regulations for the use of each underground space for use as a museum must be developed by professionals, but this space should be managed by ordinary museum workers, just as it is not necessary to be a professional mechanic to drive a car.

Besides the air conditioning, removing the water one of the most serious problems in the use of unsupported underground space is the control of the stability of the roof and walls of the workings to provide safety for visiting this museum people.

The authors propose some solutions to control the stability of mining workings using instrumental observation methods developed specifically for unprofessional workers in such underground museums.

How to cite: Ivanov, A., Shekov, K., Shekov, V., Fuławka, K., and Pytel, W.: Safety issues when using a museums in unused mining workings, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20188, https://doi.org/10.5194/egusphere-egu2020-20188, 2020.

EGU2020-4443 | Displays | GI5.7

Cautions blasting in vicinity of underground laboratories

Marcin Szumny, Krzysztof Fuławka, and Piotr Mertuszka

Development of the new mining technologies is inherently connected with scientific researches. In many cases, there must be done in very specific and demanding conditions what is possible in underground laboratories only. These facilities can be located in tunnels or chambers deep below the surface. In this kind of underground objects very specific and sophisticated scientific devices are often used. Modern technical equipment is frequently very sensitive and must be protected from various undesirable factors e.g. vibrations. During the lifetime of some underground facilities, located in the hard rocks there  could be the necessity to perform works where explosives have to be applied. One of the unwanted effects of explosives usage in rock is generation of the seismic waves.Vibrations inducted by seismic wavescan generate additional seismic load on the support of the underground facility and damage sensitive scientific devices. In this kind of blasting works, called caution blasting, there are strict restrictions for maximum vibration level that cannot be exceeded. In these kind of situations there must be used explosives and technologies that ensure fulfilling these kinds demands and restrictions. In this paper, prepared in the framework of in The Baltic Sea Underground Innovation Network (BSUIN) project, there are shown some solutions that could be applied during blasting works perform in the vicinity of protected facilities.

How to cite: Szumny, M., Fuławka, K., and Mertuszka, P.: Cautions blasting in vicinity of underground laboratories, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4443, https://doi.org/10.5194/egusphere-egu2020-4443, 2020.

Abstract. The use of parametric modeling, similar to BIM (Building Information Model) technology, widely used now in the building construction industry, and very interesting to use this approach in documenting and modeling underground space.

Unlike construction sites, not reinforced tunnels and underground workings have a very large specific associated with the properties of the surrounding rocks, which are described by specific technical and physical parameters, taking into account their resistance over a long period while using them for the purpose of extracting a useful fossil.

Geotechnical modules built into Autodesk products are designed to solve specific problems in the construction of concrete tunnels and other facilities related to the bowels. A geological model in that module is a collection of AutoCAD® Civil 3D® triangulation models (planar surfaces) that display the top and bottom of geological layers, indicating the thickness of the geological layer and tracing the boundaries of the surfaces. Solid-state models are formed only at the locations of geological wells, illustrating their composition using conditional 3D AutoCAD® bodies constructed in accordance with good patterns.

Authors of this presentation propose the primitive families for the description of the geological and structural composition of rocks around the not reinforced tunnels are being developed for the Autodesk Civil 3D and Revit program.

At the same time the use of the FreeCAD program, which supports the exchange of parametric data in the IFC (Industrial Foundation Classes) format, can be also very promising, which means that the primitives developed in this program can be used in the Autodesk software too.

Parametric models of rock in the workings can play the role of the information model while calculating the stress, deformations, heat distribution and other physical fields for different technical applications. As an Open Source software with sufficiently developed tools for modeling and parametric description of models based on information modeling, with a certain adaptation, FreeCAD program can be used for this tasks, it can also be used as the basis for creating a unified information system for underground laboratories at different scale of accuracy needed for any calculations.

How to cite: Shekov, V. and Ivanov, A.: The use of parametric modeling as the geological description of the surrounding rocks in the workings., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14254, https://doi.org/10.5194/egusphere-egu2020-14254, 2020.

EGU2020-8120 | Displays | GI5.7

Multiscale 3D stress field modelling for the URL 'Reiche Zeche' using a discontinuum model approach

Sebastian Rehde and Prof. Dr.-Ing. habil. Heinz Konietzky

Underneath the small town of Freiberg, Saxony, stretches the ore mine complex 'Reiche Zeche'. The underground laboratory (URL) inside the mine was inaugurated in 1919 and is an internationally acknowledged institution for experimental work of variable scales and subjects. Our work is part of the Stimtec project, which aims on improving planning and conducting hydraulic stimulation in anisotropic, crystalline rocks. The project comprises numerical modelling and field work inside the URL. Prior to the numerical analysis, we implemented a tool to perform a slip tendency analysis of faults that were mapped along the tunnel walls at the project site. It allows to assess the slip tendency of arbitrarily oriented faults and stress fields. The tool is used for preselection of stimulation intervals, enabling identification of faults which are likely to be reactivated by hydraulic stimulation.
We perform the stress field modelling using a multiscale numerical model approach. Therefore, we set up three different sized models deriving from a large scale 3D geomodel. The geomodel contains the topography, drifts and 47 fault structures taken from mine maps. The project site and measurement points are positioned in the center of the model. From the large scale geomodel, we developed a simplified numerical model geometry with 12 major faults, disregarding the galleries. We use the distinct element code 3DEC for discontinuous numerical modelling of the stress field. This allows to take into account discrete displacements along the faults. Far field stress is taken from previous investigations and literature as boundary and initial conditions. The resulting stress  field provides the stress tensors for calculating the corresponding forces for each gridpoint at the model boundaries of the small scale model. The small scale numerical model is smaller by a factor of 10, including two major fault segments, the galleries and mapped local faults. Hydraulic fracturing stress measurements taken during the field tests indicate that the stress field is strongly distorted in the vicinity of the tunnels and excavations along the ore veins. Hence, we developed a third model approach, a 2.5D slice model, to investigate the influence of the assumed excavation damage zones.
With this work, we provide an approach to predict the stress field inside the complex, anisotropic rock volume. Within the framework of the Stimtec project, we developed a workflow for planning hydraulic stimulation tests and 3D geological models for a diverse set of further appliations in the URL 'Reiche Zeche'.

How to cite: Rehde, S. and Konietzky, P. Dr.-Ing. H. H.: Multiscale 3D stress field modelling for the URL 'Reiche Zeche' using a discontinuum model approach, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8120, https://doi.org/10.5194/egusphere-egu2020-8120, 2020.

EGU2020-13477 | Displays | GI5.7

CHENILLE : Coupled beHaviour undErstaNdIng of fauLts : from the Laboratory to the fiEld

Audrey Bonnelye, Pierre Dick, Stefan Lüth, Jan Henninges, Grzegorz Kwiatek, Anja Scleicher, Alexandre Dimanov, Jérôme Fortin, and Fabrice Cotton

The understanding of the coupled thermo-hydro-mechanical behaviour of fault zones is of fundamental importance for a variety of societal and economic reasons, such as the sustainable energy transition for the safe use of natural resources (energy storage, nuclear waste disposal or geothermal energy). The overall objective of this inter-disciplinary project is to create a dataset that will allow to highlight the physical processes resulting from a thermal and hydric load on an existing, identified and characterized fault zone.

 

An in situ experiment will be performed at IRSN’s Tournemire Underground Research Laboratory to evaluate the hydraulic properties and mechanical behaviour of a fault zone in a shale formation due to an increase of gas or water pressure under incremental thermal loading. This fracturing field tests will be conducted using four types of boreholes drilled from the URL : (i) one injection borehole (INJ) with one chamber measuring 10 m in length; (ii) four boreholes (H1 to H4) dedicated to host steel canister electrical heaters, (iii) 5 boreholes (S1 to S5) dedicated to the geophysical monitoring of seismic and aseismic fracturing processes, (iv) two to four boreholes (M1 to M4) to record deformation and estimate fracture location, which will help assess the seismic survey. After an initial saturation phase of the chamber, successive sequences of fluid injection tests are planned. The preliminary injection tests will be done stepwise either at constant flow or at constant pressure rate in order to obtain a steady-state flow regime at normal in situ temperatures. The hydraulic conductivity and permeability of the fault zone will be then inferred. A second stage of hydraulic testing will involve the determination of the main hydraulic parameters during a stepwise increase of temperature within the volume (maximum temperature 150°C). In the meantime, the seismological responses of the injected structures, from the static deformation to the high-frequency (100-kHz) acoustic emissions will be surveyed. The evolution of temperature and deformation will be monitored thanks to fibre optic array. In addition, a controlled seismic experiment is proposed, using coupled magnetostrictive vibrators to investigate the structural environment before and after experiment.

 

Moreover, to accompany the field study, a series of laboratory experiments will be conducted to understand the chemical and structural evolution occurring within fault zones during the thermal and hydraulic loading. Experiments in climatic chambers exposing the samples to the same heat treatment as that of the in situ experiment will be carried out in order to compare the mineralogical composition evolution of the samples with those taken from the field investigated zone. Finally, a rock mechanical study, from the microscopic to the centimeter scale with monitoring of the acoustic properties will be carried out. This study will include experiments from Scanning Electron Microscope with Energy Dispersive Spectroscopy (SEM-EDS) allowing the identification of the micro-scale mechanisms of deformation localization to which it is planned to add an acoustic measurement system. In order to study the evolution of mechanical behaviour as a function of scale, experiments in triaxial press, again with acoustic monitoring, are planned.

How to cite: Bonnelye, A., Dick, P., Lüth, S., Henninges, J., Kwiatek, G., Scleicher, A., Dimanov, A., Fortin, J., and Cotton, F.: CHENILLE : Coupled beHaviour undErstaNdIng of fauLts : from the Laboratory to the fiEld, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13477, https://doi.org/10.5194/egusphere-egu2020-13477, 2020.

EGU2020-14117 | Displays | GI5.7

The STIMTEC experiment at the Reiche Zeche ULab

Carolin Boese, joerg Renner, and Georg Dresen and the STIMTEC Team

Between early 2018 and late 2019 the STIMTEC hydraulic stimulation experiment was performed at ca.~130 m below surface at the Reiche Zeche research mine in Freiberg, Saxony/Germany. The project aims at gaining insight into the creation and growth of fractures in anisotropic and heterogeneous crystalline rock units, to develop and optimise hydraulic stimulation techniques and to control the associated induced seismicity under in situ conditions at the mine-scale. These aspects of failure and associated seismicity are important for the development of enhanced geothermal energy systems. We present the infrastructure developed for the STIMTEC experiment and provide an overview of the obtained data, including 295 m of core material retrieved from 17 boreholes, 225 m of acoustic TV log, >50 TB of continuous passive seismic data from four field stimulation and hydraulic testing campaigns, as well as ~300 active velocity calibration measurements.

We highlight some of the first results regarding the hydro-mechanical and seismic response to the stimulation, the rock mass characterisation in-situ and in the laboratory, as well as 3-D numerical modelling of the stress state and fracturing. The heterogeneity and anisotropy of the strongly foliated metamorphic gneiss significantly affects fracture creation and propagation in the experiment.

How to cite: Boese, C., Renner, J., and Dresen, G. and the STIMTEC Team: The STIMTEC experiment at the Reiche Zeche ULab, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14117, https://doi.org/10.5194/egusphere-egu2020-14117, 2020.

EGU2020-3353 | Displays | GI5.7

Characteristics of natural neutron radiation background performed within the BSUIN project.

Karol Jedrzejczak, Marcin Kasztelan, Jacek Szabelski, Przemysław Tokarski, Jerzy Orzechowski, Włodzimierz Marszał, and Marika Przybylak

The BSUIN (Baltic Sea Underground Innovation Network) aims to enhance the accessibility of the underground laboratories in the Baltic Sea region for innovation, business and science. One of the BSUIN project activities is characterization of natural background radiation (NBR) in underground facilities. A specific type of NRB is neutron radiation, whose measurement requires specific instruments and long-term exposure in-situ, in heavy underground conditions.

In this talk the method of natural neutron radiation background will be presented as well as results of pilot measurements in several underground locations. In order to make this measurements, a measuring setup was designed and made. The setup design is closely matched to the task: the setup is scalable in a wide range, completely remotely controlled (via the Internet) and capable of long-term operation (months).

The pilot measurements were performed in Callio Lab, Pyhäsalmi, Finland, (4100 m w.e.), in Reiche Zeche mine in Freiberg, Germany (410 m w.e.) and in Experimental Mine “Barbara” in Mikołów, Poland (100 m w.e).

How to cite: Jedrzejczak, K., Kasztelan, M., Szabelski, J., Tokarski, P., Orzechowski, J., Marszał, W., and Przybylak, M.: Characteristics of natural neutron radiation background performed within the BSUIN project., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3353, https://doi.org/10.5194/egusphere-egu2020-3353, 2020.

EGU2020-2979 | Displays | GI5.7

Characteristics of natural radiation background at the Callio Lab (Finland) performed within the BSUIN project

Jan Kisiel, Kinga Polaczek-Grelik, Katarzyna Szkliniarz, Agata Walencik-Łata, Jari Joutsenvaara, Hannah Puputti, Marko Holma, and Timo Enquist

The BSUIN (Baltic Sea Underground Innovation Network) aims to enhance the accessibility of the underground laboratories in the Baltic Sea region for innovation, business and science. One of the BSUIN project activities is characterization of natural background radiation (NBR) in underground facilities. In this talk results from NBR measurements performed in Callio Lab, Pyhäsalmi, Finland, at the depth of 4100 m w.e. will be presented. The in-situ gamma spectra were collected with the use of  HPGe semiconductor spectrometer, whereas the  concentration of radon were measured with RAD7 electronic detector. In addition, the water and rock samples were taken for laboratory analysis in Institute of Physics, University of Silesia, Poland. The concentration radioisotopes in water samples were performed by using a liquid scintillation α/β counter (LSC) and α-particle spectrometry, while the concentration of radioisotopes in rock samples were performed by using laboratory gamma ray spectrometry and also α-particle spectrometry.

How to cite: Kisiel, J., Polaczek-Grelik, K., Szkliniarz, K., Walencik-Łata, A., Joutsenvaara, J., Puputti, H., Holma, M., and Enquist, T.: Characteristics of natural radiation background at the Callio Lab (Finland) performed within the BSUIN project, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2979, https://doi.org/10.5194/egusphere-egu2020-2979, 2020.

GI6.1 – Geoscience applications of environmental radioactivity

EGU2020-2052 | Displays | GI6.1 | Highlight

Natural Radionucdlides in Swiss Drinking Water; A Review and How to Comply with the New Regulations

Heinz Surbeck

EGU2020-1506 | Displays | GI6.1 | Highlight

Characterising diurnal- and synoptic-timescale changes in urban air quality using Radon-222

Scott Chambers, Dafina Kikaj, Agnieszka Podstawczyńska, Jagoda Crawford, and Alastair Williams

Urban air quality is strongly influenced by the atmosphere’s ability to disperse primary emissions and opportunities for secondary pollution formation. In mid- to high-latitude regions that experience enduring winter snow cover or soil freezing, regional subsidence and stagnation associated with persistent anti-cyclonic conditions such as the “Siberian High” can lead to “cold pool” or “persistent inversion” events. These events can result in life-threatening pollution episodes that last for weeks. While often associated with complex topography [1,2], persistent inversion events can also influence the air quality of urban centres in flat, inland regions [3]. This presentation will describe a recently-developed radon-based technique for identifying and characterising synoptic-timescale persistent inversion events, which is proving to be a simple and economical alternative to contemporary meteorological approaches that require regular sonde profiles [1]. Furthermore, key assumptions of the radon-based technique to characterise diurnal-timescale changes in the atmospheric mixing state described by Chambers et al. [4] are violated during persistent inversion conditions. Here we demonstrate how atmospheric class-typing, through successive application of radon-based techniques for identifying synoptic- and diurnal-timescale changes in the atmospheric mixing state, improves understanding of atmospheric controls on urban air quality in non-summer months across the full diurnal cycle. This knowledge translates directly to statistically-robust techniques for assessing public exposure to pollution, and for evaluating the efficacy of pollution mitigation measures. Lastly, we show how atmospheric class-typing can be used to enhance the evaluation of chemical transport models [5].

[1] Baasandorj, M., et al. Environ. Sci. Technol., 51, 5941–5950, https://doi.org/10.1021/acs.est.6b06603, 2017.

[2] Kikaj, D., et al. Atmos. Meas. Tech., 12, 4455–4477, https://doi.org/10.5194/amt-12-4455-2019, 2019.

[3] Chambers, SD and A Podstawczyńska. Atmos. Environ., 219, 117040, https://doi.org/10.1016/j.atmosenv.2019.117040, 2019.

[4] Chambers, S.D., et al. J. Geophys. Res. Atmos. 124, 770–788, https://doi.org/10.1029/2018JD029507, 2019.

[5] Chambers, S.D., et al. Atmosphere 10 (1), 25, doi:10.3390/atmos10010025, 2019.

How to cite: Chambers, S., Kikaj, D., Podstawczyńska, A., Crawford, J., and Williams, A.: Characterising diurnal- and synoptic-timescale changes in urban air quality using Radon-222, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1506, https://doi.org/10.5194/egusphere-egu2020-1506, 2020.

EGU2020-10467 | Displays | GI6.1

Assessment of regional atmospheric transport model performance using 222Radon observations

Ute Karstens, Ingeborg Levin, Michel Ramonet, Christoph Gerbig, Sabrina Arnold, Sebastién Conil, Julian Della Coletta, Arnoud Frumau, François Gheusi, Victor Kazan, Dagmar Kubistin, Matthias Lindauer, Morgan Lopez, Lars Maurer, Nikos Mihalopoulos, Jean-Marc Pichon, and Gerard Spain

The rather short life time of 222Radon of 5.5 days makes this radioactive noble gas an almost ideal tracer of atmospheric transport processes. 222Radon, the gaseous progeny of 226Radium, which is a trace constituent of all soils, can escape the soil grains and make its way from the unsaturated soil zone into the atmosphere. The exhalation rate of 222Radon from continental surfaces depends on soil type and permeability, but is orders of magnitude larger than that from ocean surfaces. Therefore, the atmospheric 222Radon activity concentration can be used as a measure of the residence time of air over continental surfaces or to distinguish continental from marine air masses. At continental sites, the short-term variability of 222Radon is mainly determined by diurnal or synoptic-scale boundary layer mixing processes. If its continental exhalation rate is known, 222Radon can even be applied as a quantitative tracer for evaluating regional scale transport model performance. In the present study we use 222Radon activity concentration measurements from the ICOS atmospheric station network and STILT transport model results to assess the ability of this routinely used model to correctly simulate the (diurnal) variation of boundary layer transport. This uncertainty assessment is an important step towards reliable estimates of the contribution of transport model error in GHGs inversion studies that aim at providing accurate fluxes from inversion of atmospheric GHGs observations in ICOS.  

How to cite: Karstens, U., Levin, I., Ramonet, M., Gerbig, C., Arnold, S., Conil, S., Della Coletta, J., Frumau, A., Gheusi, F., Kazan, V., Kubistin, D., Lindauer, M., Lopez, M., Maurer, L., Mihalopoulos, N., Pichon, J.-M., and Spain, G.: Assessment of regional atmospheric transport model performance using 222Radon observations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10467, https://doi.org/10.5194/egusphere-egu2020-10467, 2020.

EGU2020-4944 | Displays | GI6.1 | Highlight

Using Safecast data for estimating ambient dose rate in cities around the world

Petr Kuča and Peter Bossew

Using Safecast data for estimating ambient dose rate in cities around the world

Petr KUČA1 and Peter Bossew2

1 National Radiation Protection Institute (SURO), Praha, Czech Republic 

2 German Federal Office for Radiation Protection, Berlin

 

Safecast [1] is a citizen science project, aimed to environmental monitoring. Its main activity is measuring ambient dose rate (ADR) all over the world. Motivated by the Fukushima NPP accident in March 2011, the project started soon after, and since, numerous citizens have contributed, carrying monitors with them.

In this presentation, the Safecast project is introduced together with its standard instrument for ADR measurement, called bGeigie Nano. We discuss matters of quality assurance connected to data generation mainly by citizens who are generally no trained metrologists, and consequently, interpretation problems of Safecast data.

The freely accessible data, currently (January 2020) over 120 million observations, were used to calculate mean ADR in various cities around the world where sufficient data is available. The resulting geographical pattern mainly reflects the variability of dose rate from terrestrial radiation, which is controlled by the one of geochemistry, namely the concentrations of uranium, thorium and potassium. Further influence comes from cosmic radiation, natural radionuclides in the air (a small contribution) and in a few cases, from anthropogenic radiation caused by nuclear fallout.

In some cities at high altitude, such as Cusco (Peru), Nairobi (Kenia) or Denver (USA), secondary cosmic radiation clearly contributes strongly to ADR. In low to medium altitude, cosmic dose rate varies relatively little, so that it contributes little to the geographical pattern. Apart from the regional geological background, ADR is generated by building materials typical for an urban environment. Mean terrestrial ADR in cities around the world ranges between several 10 nSv/h and several 100 nSv/h. Anthropogenic radiation contributes little, except close to areas affected by the Chernobyl and Fukushima accidents. However, one can argue that also radiation from building materials, although originating from natural radionuclides, is anthropogenic, as buildings are anthropogenic objects and the choice of building materials is an anthropogenic one.

We show maps displaying mean ADR for a number of cities. Geology and in some cases, altitude above sea level are clearly reflected in these maps. Besides, we address statistical issues related to spatial dispersion of ADR and of data clustering as resulting from varying and heterogeneous sampling density. Finally, we discuss merits of the Safecast project as well as inevitable limitations.

[1] www.safecast.org ; Brown, A., Franken, P., Bonner, S., Dolezal, N., Moross, J. (2016): Safecast: successful citizen-science for radiation measurement and communication after Fukushima. Journal of Radiological Protection, 36 (2), S82 – S101; doi:10.1088/0952-4746/36/2/s82

How to cite: Kuča, P. and Bossew, P.: Using Safecast data for estimating ambient dose rate in cities around the world, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4944, https://doi.org/10.5194/egusphere-egu2020-4944, 2020.

A detailed investigation of geogenic radon potential (GRP) was carried out using geostatistical analysis on multiple radon-related variables to evaluate natural radiation in an area of Southeast Ireland. The geological setting of the study area includes basal Devonian sandstones and conglomerates overlying an offshoot of the Caledonian Leinster Granite, which intrudes Ordovician sediments. The Ordovician sediments contain traces of autunite (Ca(UO2)2(PO4)2·10–12H2O), which is a uranium-bearing mineral and a source of radon. To model radon release potential at different locations, a spatial regression model was developed in which soil gas radon concentration measured in-situ using a Radon RM-2 detector was considered as a response value. Proxy variables such as local geology, soil types, terrestrial gamma dose rates, radionuclide concentrations from airborne radiometric surveys, soil gas permeability, distance from major faults and a Digital Terrain Model were used as the main predictors. Furthermore, the distribution of indoor radon concentration was simulated using a soil-indoor transfer factor. Finally, the workability of the proposed GRP model was tested by evaluating the correlation between previously measured indoor radon concentrations and the estimated values by the GRP model at the same measurement locations. This model can also be used to estimate the GRPs of other areas where radon-related proxy values are available.        

Keywords: Natural radiation, geogenic radon potential, geostatistical analysis, spatial regression model, indoor radon simulation

How to cite: Mousavi, M. and Crowley, Q.: Geogenic radon potential mapping using geospatial analysis of multiple radon-related variables: a case study from Southeastern Ireland, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4884, https://doi.org/10.5194/egusphere-egu2020-4884, 2020.

EGU2020-5327 | Displays | GI6.1 | Highlight

Multiscale UAS Radiation Mapping Within the Chernobyl Exclusion Zone (CEZ).

Dean Connor, Kieran Wood, Peter Martin, Yannick Verbelen, Sevda Goren, Erin Holland, David Megson-Smith, Nick Smith, Thomas Richardson, and Thomas Scott

The accident occurring at the Chernobyl Nuclear Power Plant (ChNPP) in 1986 remains the most prolific in the history of civil nuclear power generation. In the decades since the incident, remote characterisation technologies have advanced significantly in their capabilities. Current knowledge of 137Cs distribution within the CEZ is provided by extensive ground sampling investigations conducted at the turn of the millennium. Whilst this method has a high degree of accuracy, it does not allow for local-scale variation to be resolved. Furthermore, the physical collection of samples is labour intensive and suffers from inconsistent sampling densities throughout the extent of the surveyed area. Inconsistent data spacing occurs due to time and resource constraints, terrain difficulties and exposure risk from the physical radiation hazard, which all relate to using humans to collect the samples. Airborne monitoring using UASs is a solution to overcoming the drawbacks experienced from ground-based sampling, albeit coming at a loss of absolute measurement accuracy. This method allows for the creation of a consistent network of sampling points at a high resolution, independent from terrain conditions and without exposing the operators to potentially harmful doses of radiation.

This work presents a comprehensive UAS radiation mapping investigation aiming to evaluate the 137Cs distribution within the CEZ using two distinct radiation mapping UASs to conduct surveys at different spatial resolutions. The first comprises of a lightweight (8 kg) fixed-wing UAS equipped with a dual detector payload (2 x 32.8 cm3 CsI[Tl] detectors) to map over large areas at a relatively high forward velocity (14 – 18 m s-1) and a  medium-low spatial resolution (20 – 60 m pixel-1). A multi-rotor aerial vehicle is preferred for the second system, which was used to monitor smaller areas of interest (highlighted by the fixed-wing survey), at a higher spatial resolution (3 – 10 m pixel-1) and a much lower forward velocity of approximately 3 m s-1. This system was heavier than the fixed-wing variant, weighing approximately 11 kg.

In the seven days of active fieldwork in the CEZ, more than 650 km of combined flight distance was covered by the two systems, characterising a total area of approximately 15 km2. Through a series of carefully calibrated processing algorithms, both the 137Cs activity (in kBq m-2) and the dose-rate (µSv hr-1) resulting from 137Cs deposition at one metre above ground level are evaluated. Error propagation through this procedure indicates a base-rate error of 11.5-13.9% in the estimation of 137Cs activity from the air, while the basal error for the dose-rate estimation is lower at approximately 5.5 – 6.2%. Minimum detectable activity (MDA) was calculated as 98.1 ± 0.4 kBq m-2 for the fixed-wing system operating at 40 - 60 m altitude and 33.5 ± 0.9 kBq m-2 for the multi-rotor at 8 - 20 m altitude.

How to cite: Connor, D., Wood, K., Martin, P., Verbelen, Y., Goren, S., Holland, E., Megson-Smith, D., Smith, N., Richardson, T., and Scott, T.: Multiscale UAS Radiation Mapping Within the Chernobyl Exclusion Zone (CEZ)., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5327, https://doi.org/10.5194/egusphere-egu2020-5327, 2020.

EGU2020-4786 | Displays | GI6.1

Simulation of airborne gamma-ray data

Malte Ibs-von Seht

Planning and conduct of aircraft- or drone-based gamma-ray spectrometry surveys may raise the need to simulate and explore the radiation flux from the ground for airborne measurement geometries. Presented here is a simple yet powerful approach to simulating the count rates of gamma-rays measured with standard airborne detector systems and processed with the conventional window method.

The window method is based on energy windows within the gamma spectrum that are associated with the three naturally occurring radioelements potassium, uranium, and thorium. Various correction and processing steps are applied to the integral window count rates using system specific calibration parameters such as stripping ratios, sensitivities and background values to finally derive ground concentrations of the three elements. For a simulation of such gamma-ray data, the count rates produced by the sources to be simulated and recorded by a particular measuring system in a particular geometry must be calculated and noise with matching statistical properties be applied to them. This means that the well-known steps for airborne gamma-ray processing, described e.g. in IAEA (2003), have to be performed in reverse order. This approach reveals some interesting insights into the capabilities and limitations of the airborne radiometrics method.

The simulation process itself starts with the design of the simulated survey features. This includes the survey area location and size, the course and spacing of the survey lines and the sampling distance. From these parameters, a dataset is constructed that contains the positions of the sampling points. Also, the relevant system parameters are defined. In the next step, the radiometric conditions of the area are designed. This is done by discretizing the survey area in grid cells and assigning concentration values to each cell according to the desired ground source distribution. Count rates for each grid cell can now be calculated and the count rate grids are subsequently processed using a geometric response filter that simulates the footprint properties of the detector at the selected survey height. Finally, after applying noise of matching statistical properties to the filtered grids, they are scanned along the sampling positions, leading to a dataset that contains the simulated airborne gamma-ray data.

The simulated dataset can be utilized in various ways to explore the influences of survey, system, source and environmental parameters on the recorded window count rates. The benefit of the proposed approach is that common workflow procedures as preferred by the user can be directly applied to the data and the resulting maps can be inspected in the usual way. Furthermore, processing algorithms and methods such as filtering and statistical levelling can be tested and optimised. In this contribution, the way the simulation works is outlined and the results are illustrated by means of various examples.

IAEA, 2003. Guidelines for radioelement mapping using gamma ray spectrometry data. IAEA-TECDOC No. 1363, Vienna.

How to cite: Ibs-von Seht, M.: Simulation of airborne gamma-ray data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4786, https://doi.org/10.5194/egusphere-egu2020-4786, 2020.

EGU2020-1195 | Displays | GI6.1

Spatial variation of Cs-137 activity concentration in urban environment using attic dust samples from city of Salgotarjan in northern part of Hungary

Davaakhuu Tserendorj, Peter Völgyesi, Katalin Zsuzsanna Szabó, Gorkhmaz Abbaszade, Do Le Tan, Nelson Salazar, Dora Zacháry, Tam Cong Nguyen Cong Nguyen, and Csaba Szabó

*davaakhuu@caesar.elte.hu

The 137Cs is a principal radioisotope introduced into the environment through the atmospheric bomb tests (from 50s to 60s) and the major nuclear accidents (Chernobyl, 1986 and Fukushima, 2011).  From atmosphere, 137Cs adsorbs to precipitation and returns to lithosphere by wet and dry deposition as radioactive fallout component.  Due to the Chernobyl nuclear accident, the released contaminated air mass contained particles with attached Cs, largely propagated, deposited and distributed across northern and eastern European countries in the ambient environment (Balonov et al., 1996) in case of Fukushima disaster also contributes to the increase, but only by minor amount.  These particles could have reached the houses (e.g. through open windows, doors, fractures, and vents) in urban environment and deposited inside resulting in the exposition of the habitants to 137Cs.  In areas that are not accessible for regular cleaning (e.g., attics) physical state and chemical composition of attic dusts remain constant i.e. unchanged in time.

Accordingly, undisturbed attic dust samples from Salgótarján (Hungary), a former heavy industrial city, were collected and studied as past records of anthropogenic pollution, with intention of elucidating the pathways of radioactive contamination in urban environment.

The specific activity of Cs-137 was measured in 36 attic dust samples.  Construction ages of the selected houses range from 1880 to1989, a selection criterion superimposed on the 1x1 km grid design. The Homogenized samples (amount: 1-1.5 g, grain size: <0.125 mm) were analyzed by a well-type HPGe detector placed in a low-background iron chamber at the laboratory of the Hungarian Center for Energy Research.  The obtained 137Cs activity ranges from 4.34 ± 0.27 Bq/kg -1 to 140.74 ± 1.66 Bq/kg -1 (Detection limit: 0.75 Bq/kg -1).  Arithmetic mean of the values is 73.32 ± 1.58 Bq/kg -1, whereas geometric mean and standard deviation is 59 ± 1.36 Bq/kg -1 and 39.83 ± 0.76 Bq/kg -1, respectively (all decay corrected into year of sampling, 2016). Specific activity of radionuclide is higher than result published in other regions of Hungary and neighboring countries.  This confirms that attic dust is very effective material for monitoring past fallouts of production from early nuclear weapon testing and nuclear catastrophe(s).

Our results performed that a higher activity concentration of 137Cs is found in the oldest houses (1890-1970) were present in the high elevated areas. Thus, it indicates that deposition of 137Cs was strongly influenced by local physical conditions (geomorphology and meteorology).  Due to the geostatistical analysis, interpolation was done with ordinary point kriging using the obtained variogram model.  Adjusted model shows a best fit (r2=0.606) with spherical model.  The results of 137Cs activity concentration suggest a good spatial dependency verifying our sampling strategy.  Therefore, it can be considered that attic dust remained undisturbed for decades and preserve past records of components of atmospheric pollution.

Keywords: attic dust, 137Cs activity concentration, geostatistical analysis, urban environment, high altitude, Hungary

Reference:

Balonov, M., Jacob, P. és Minenko, V. (1996) Pathways, Levels and Trends of Population Exposure after the Chernobyl Accident, Radiological Consequences of the Chernobyl Accident.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

How to cite: Tserendorj, D., Völgyesi, P., Szabó, K. Z., Abbaszade, G., Le Tan, D., Salazar, N., Zacháry, D., Cong Nguyen, T. C. N., and Szabó, C.: Spatial variation of Cs-137 activity concentration in urban environment using attic dust samples from city of Salgotarjan in northern part of Hungary, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1195, https://doi.org/10.5194/egusphere-egu2020-1195, 2020.

EGU2020-4672 | Displays | GI6.1

Using geogenic radon potential to assess designation of radon priority areas in Ireland

Meabh Hughes and Quentin Crowley

Radon is a radioactive gas which emanates from rock, soil and water. Radon concentrations in the
atmosphere are generally very low (typically <5 Bq m-3), however it can occur at much higher levels
in soil (typically 10’s-100’s kBq m-3), or enclosed spaces such as buildings and caves (typically 10’s-
100’s Bq m-3). Exposure to radon and its daughter products is associated with an elevated risk of
developing lung cancer. Ireland has a population weighted indoor radon concentration of 98 Bq m-3
resulting in an estimated 300 annual lung cancer cases per year, representing approximately 12% of
the annual lung cancer cases. A national-scale legislative radon-risk map has a 10 x 10 km spatial
resolution and is based exclusively on indoor radon measurements (i.e. it does not contain any
geological information). The legislative map satisfies the European Council Directive
2013/59/EURATOM Basic Safety Standard, in that it defines “high radon” areas as those where >10%
of homes are estimated to exceed the national reference level of 200 Bq m-3. New buildings in such
areas are legally required to have a barrier, with low radon permeability installed.

This research focuses on a karstic region of SE Ireland, which features some exceptionally high
indoor radon concentrations (65,000 Bq m-3), even though it is not classified as a “high radon” area
on the national legislative map. Here we demonstrate the use of measuring sub-soil radon
concentrations and sub-soil permeability, in order to construct a radon potential (RP) map of the
area. Extremely high sub-soil radon concentrations (>1443 kBqm-3) and radon potential values
(>200) are spatially associated with Namurian shales, interbedded with limestone. Overall, we
classify the study area as high radon potential (RP >35) using this technique. We suggest all areas
underlain by Namurian shales in Ireland should undergo similar radon potential mapping, and if
necessary, should be re-designated as “high radon” areas. If deemed appropriate (i.e. where RP
>35), such a designation will help to protect the general public from the harmful effects of indoor
radon exposure, and will help to lower the incidence of radon-related lung cancer in these areas.

How to cite: Hughes, M. and Crowley, Q.: Using geogenic radon potential to assess designation of radon priority areas in Ireland, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4672, https://doi.org/10.5194/egusphere-egu2020-4672, 2020.

EGU2020-5074 | Displays | GI6.1

Gamma spectra from uranium mining residues simulated for airborne geometries and detectors

Benedikt Preugschat and Malte Ibs-von Seht

Legacies from uranium mining pose an acute risk to human health and the environment in Central Asia in the countries of Kyrgyzstan, Tajikistan, Uzbekistan and Kazakhstan. This risk is due to the emission of radioactive radiation and the potential contamination of groundwater with radionuclides from the mining residues. A precise knowledge of the location and the contained concentrations of these contaminated sites is necessary in order to obtain an assessment of the hazard and to define areas with the highest remediation priority.

The Federal Institute for Geosciences and Natural Resources in Germany (BGR) currently carries out the project DUB-GEM (Development of a UAV-based Gamma spectrometry for the Exploration and Monitoring of Uranium Mining Legacies), funded by the German Federal Ministry of Education and Research. Within the project, an Unmanned Aerial Vehicle (UAV) based system is to be developed with which the exploration of contaminated sites can be carried out both with low risk for the measurement technician and quickly and cheaply. The challenge lies in the nuclide-specific determination and differentiation of heap and tailing materials with airborne measurements and scintillation detectors. Due to the low spectral resolution of such detectors, this was not possible for a long time. However, with new technologies, scintillation materials and better computer algorithms there is now a potential to solve the problem.

In the DUB-GEM project, one of the detectors to be used will be a large volume (600 ml) CeBr3-detector. In preparation for the field campaign in 2021, we calculated theoretical gamma spectra for this detector using Monte Carlo simulations with the program MCNP6. The simulations were done for varying survey parameters such as flying height and speed, as well as for varying source parameters such as nuclide-specific composition and ground distribution of the mining residues to be mapped. The results of the theoretical investigations will be used to design and optimize survey parameters and to estimate minimum detectable activities.

How to cite: Preugschat, B. and Ibs-von Seht, M.: Gamma spectra from uranium mining residues simulated for airborne geometries and detectors, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5074, https://doi.org/10.5194/egusphere-egu2020-5074, 2020.

EGU2020-8436 | Displays | GI6.1

Natural gamma radiation in La Palma Island, Canary Islands, Spain

María López-Pérez, Pedro Ángel Salazar-Carballo, M. Candelaría Martín-Luis, José Miguel Lorenzo-Salazar, Xiomara Duarte-Rodríguez, Antonio Catalán-Acosta, Álvaro Gijón-Aguado, and José Hernández-Armas

The Canary Islands are an archipelago with an area of 7,447 km2 comprising seven main islands and some islets, located about 90 km off the northwest coast of Africa. La Palma is the most active volcanic island of the Canarian archipelago in historical times (after XV Century), with an area of 706 km2 and about 83,000 inhabitants. From the geochemical point of view, La Palma is characterized by alkaline rocks ranging from basanites and alkali picrites to phonolites. Despite the different geological units essentially overlap in their bulk chemical compositions, there are significant differences.

Measurements of natural gamma radiation were carried out in 71 sites randomly selected on a predefined 3x3 km sampling grid covering the whole island in 2013. Total outdoor gamma radiation levels were measured at 1 m above the ground. Air gamma radiation was measured by means of a MINI 6-80 (Mini-Instruments) monitor equipped with an energy-compensated Geiger-Müller MC-71 probe and FH 40 GL 10 (ThermoFischer Scientific) dosimeter equipped with a proportional-gas detector. The background radiation was calculated for each sampling site and subtracted for each dose measurement. Additionally, 25 soil samples were collected at a depth of 0-15 cm in uncultivated fields. Radiometric measurements for 40K, 226Ra and 232Th radioisotopes were performed by low-level gamma spectrometry with coaxial-type germanium detectors (Canberra Industries Inc., USA).

The gamma absorbed dose rates showed a log-normal distribution, ranging from 37.2 up to 134.0 nGy·h-1, with a geometric mean of 64.5 nGy·h-1. The observed mean gamma absorbed dose rate in La Palma Island was higher than those measured in La Gomera Island (43.9 nGy·h-1), and lower than those measured in Tenerife (89.2 nGy·h-1) and El Hierro islands (93.3 nGy·h-1) (publication in preparation). The geometric means of 40K, 226Ra and 232Th activity concentration were 216.1 Bq·Kg-1, 22.0 Bq·Kg-1 and 23.6 Bq·Kg-1, respectively.

Maps with the spatial distribution of the terrestrial natural gamma radiation and 40K, 226Ra and 232Th radioisotopes were also prepared and compared with the geochemical composition of soils. Contour maps for the terrestrial radiation component of the absorbed dose rate and radioisotope distributions were obtained using ordinary Kriging interpolation. Lower absorbed dose rates (between 45 and 70 nGy h-1) were observed in the oldest northern part of the island, corresponding to the Taburiente and Garafía basaltic shields. Two anomalies were found with absorbed dose rate values between 80 and 110 nGy h-1. The first one is located at the Bejenado stratovolcano, extending north to the Caldera de Taburiente, and south to the Aridane Valley. The second anomaly was found in the southeastern part of the Cumbre Vieja ridge. This last volcanic edifice corresponds to the youngest part of the island, where several historical eruptions have occurred. These anomalies might be related to phonotrephritic and phonolitic rocks identified at the upper part of the Bejenado sequence and Cumbre Vieja edifice.

 

How to cite: López-Pérez, M., Salazar-Carballo, P. Á., Martín-Luis, M. C., Lorenzo-Salazar, J. M., Duarte-Rodríguez, X., Catalán-Acosta, A., Gijón-Aguado, Á., and Hernández-Armas, J.: Natural gamma radiation in La Palma Island, Canary Islands, Spain, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8436, https://doi.org/10.5194/egusphere-egu2020-8436, 2020.

EGU2020-12275 | Displays | GI6.1

A comparative study of the adsorption efficiency of typical adsorption materials for wastewater containing cesium

Can Du, Jinsheng Wang, Xin Liu, and Juanting Niu

In this paper, six typical adsorption materials (activated carbon, kaolin, montmorillonite, bentonite, zeolite, and attapulgite) were used to investigate the effects of adsorption time, initial concentration, pH, and temperature on the adsorption of cesium (Cs) contained in wastewater. A combination of kinetics and isotherms was used. The results revealed that, for the same adsorption time, the adsorption efficiencies of the six materials for Cs were as follows: zeolite>attapulgite>bentonite>montmorillonite>activated carbon>kaolin. The adsorption rate of zeolite to Cs ions was almost independent of the initial concentration and temperature. The removal effect of other materials improved in alkaline environments at 30℃. Attapulgite, montmorillonite, activated carbon, and kaolin could be used for the removal of Cs at low initial concentrations. The adsorptive processes utilized by the six adsorption materials were the result of a combination of various adsorption mechanisms. Among the six typical adsorption materials, zeolite, attapulgite, and bentonite had clear removal effects and could be used in practical application in which radioactive wastewater containing Cs needs to be disposed of. Our results suggest that zeolite is the best adsorption material for this purpose.

How to cite: Du, C., Wang, J., Liu, X., and Niu, J.: A comparative study of the adsorption efficiency of typical adsorption materials for wastewater containing cesium, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12275, https://doi.org/10.5194/egusphere-egu2020-12275, 2020.

EGU2020-13503 | Displays | GI6.1

UAV-based mapping of radioactive contamination of uranium mining legacies in Central Asia

Sven Altfelder, Robert Arndt, Malte Ibs-von Seht, Christian Kunze, Benedikt Preugschat, Marius Schröder, Hartmut Schulz, and Benjamin Wiens

In the Central Asian countries of Kyrgyzstan, Tajikistan, Uzbekistan and Kazakhstan, uranium production activities during the Soviet era have led to a large number of mining legacies. The mining residues can show significant levels of radioactive contamination. Due to the mountainous landscape and the geotechnical conditions at these sites, there is a risk of uncontrolled release of radioactive contaminants into the environment and into cross-border rivers in the region. The situation is exacerbated further by the fact that the countries are prone to natural hazards such as earthquakes, floods, mudflows and landslides. There is an urgent need to map locations, extent and inventory of the contaminated areas in order to be able to support remediation measures and monitor the long-term stability of the remediated legacies.
The research project DUB-GEM funded by the German Federal Ministry of Education and Research (grant no. 01LZ106A-C) deals with the development of a UAV-based gamma spectrometry for the exploration and monitoring of uranium mining legacies. The aim of the three-year project is to develop and apply a method that allows regulatory authorities and operators to map contaminated sites rapidly and economically using gamma spectrometers mounted on a UAV (unmanned aerial vehicle). The main tasks of the project are to select and configure suitable detectors, to develop flight, measurement, and data processing strategies and to design an airframe that is ideally suited to carry out the surveys. In this contribution we present the current status of the project, including the design of the UAV prototype, results of the first test and calibration measurements with the selected gamma spectrometers and an outlook on upcoming project activities.

How to cite: Altfelder, S., Arndt, R., Ibs-von Seht, M., Kunze, C., Preugschat, B., Schröder, M., Schulz, H., and Wiens, B.: UAV-based mapping of radioactive contamination of uranium mining legacies in Central Asia , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13503, https://doi.org/10.5194/egusphere-egu2020-13503, 2020.

It is necessary to develop environmentally benign methods for removing uranium from various environments due to its high toxicity and radioactivity. Among the methods, we used fungal biosoprtion using newly isolated Cladosporium sp. strain F1. Extensive absorption of presynthesized nanoplates of uranium-phosphate minerals was observed on the hyphae of the Cladosporium sp. strain F1. In addition, once soluble UO22+ species was added to the culture of Cladosporium sp. strain F1, uranium mineral plates were also observed on the surface of the fungus hyphae over a range of pH. This was confirmed by EDX analyses, and SEM, AFM, and thin sectional TEM image analyses. The maximum biosorption capacity of uranyl ions was 74.3 mg g⁻¹ at pH 6.0. In general, biosorption capacity of Cladosporium sp. strain F1 was better than that of Aspergillus niger strain to uranium minerals. In conclusion, this study showed that the newly isolated fungus Cladosporium sp. strain F1 could be a cost-effective and environmentally friendly biosorbent to remove toxic uranium from aqueous environments.

How to cite: Lee, J. and Hur, H.-G.: Uranium phosphate mineral adsorption to newly isolated fungus Cladosporium sp. strain F1, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22387, https://doi.org/10.5194/egusphere-egu2020-22387, 2020.

EGU2020-1149 | Displays | GI6.1 | Highlight

Making radioactivity measurements on building materials accessible to everyone

Andrea Serafini, Matteo Alberi, Pierluigi Carconi, Enrico Chiarelli, Pierino De Felice, Andrea Deserventi, Massimiliano Donati, Erica Fanchini, Ferdinando Giordano, Paolo Grignani, Alessandro Iovene, Luciano Luciani, Giacomo Manessi, Fabio Mantovani, Marco Marini, Massimo Morichi, Andrea Pepperosa, Kassandra Giulia Cristina Raptis, Francesco Rogo, and Virginia Strati and the CORSAIR

The CORSAIR (Cloud Oriented Radiation Sensor for Advanced Investigation of Rocks) project was born to meet the EU guidelines 2013/59/EURATOM on safety standards for protection against ionizing radiations. The project designed an automated system capable of providing a real-time measurement of the radioactive activity concentration index for building materials according to regulations of more than 20 different countries. Measurements are conducted through in situ gamma-ray spectroscopy techniques on 3 x 3 x 3 m3 blocks of rock at quarries and processing centers, and quantify the activities, the abundances and the related effective dose-rates of natural radionuclides (40K, 232Th, 238U and their progenies) in stone materials for the building industry. The detector comprises a 2” x 2” cylindric CeBr3 crystal having a 2.5% energy resolution at 1461 keV. A lateral lead shield of 1.3 cm enables a ~60% reduction of the gamma signal coming from above and beside the detector. The system is designed for providing the radiometric index in less than 30 min with an overall uncertainty of the order of 5%.

The innovative aspects of the detector are in its autonomous operation and the easy fruition of the results of the material characterization. Energy calibration and peak recognition are automatically performed on‑board through an innovative stochastic method based on simulated annealing. The computation of the results is fully-automated and requires no intervention of the operator. The battery-powered detector is equipped with GPS, LoRa, Bluetooth and Wi-Fi connectivity and can be remotely controlled thanks to a dedicated Android app. Acquired data and activity indexes are synced through LoRa connectivity to a cloud database, where they can be easily accessed by sellers and buyers, thus preventing the placing on the market of blocks hazardous to public health.

How to cite: Serafini, A., Alberi, M., Carconi, P., Chiarelli, E., De Felice, P., Deserventi, A., Donati, M., Fanchini, E., Giordano, F., Grignani, P., Iovene, A., Luciani, L., Manessi, G., Mantovani, F., Marini, M., Morichi, M., Pepperosa, A., Raptis, K. G. C., Rogo, F., and Strati, V. and the CORSAIR: Making radioactivity measurements on building materials accessible to everyone, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1149, https://doi.org/10.5194/egusphere-egu2020-1149, 2020.

EGU2020-1181 | Displays | GI6.1

How can flow system approach help to understand the natural radionuclide content of the drinking water originated from groundwater sources? Case study in the vicinity of a granitic complex

Petra Baják, Katalin Csondor, Heinz Surbeck, Bálint Izsák, Márta Vargha, Ákos Horváth, Tamás Pándics, and Anita Erőss

In groundwater, the soluble members of the uranium decay chain such as uranium, radium, and radon can be found in significant concentration. Their distribution is affected by physicochemical properties such as pH, redox potential and chemical composition of the groundwater. Uranium can be mobilised under oxidising conditions especially in the water where the pH is near neutral and has high alkalinity. In contrast, radium is mobile in reducing environment, enhanced by the presence of carbonate, sulphate, chloride. These parameters vary along the groundwater flow paths and with regard to the change of regime characteristics. Areas with recharge regime and discharge points of local flow systems are characterised by oxidising environment while discharge areas of higher-order systems tend to be reducing. The natural radioactivity of groundwater, as a possible threat for human health, has been investigated for a few decades as groundwater is a very common drinking water source. In Hungary, 96% of the water supply relies upon groundwater. Following the Euratom Drinking Water Directive the radioactivity of drinking water is screened in Hungary by gross alpha and gross beta activity measurements. Whenever the measured concentrations surpass the limit values the long-term consumption of the water can lead to health issues. High values of gross alpha activity can be found in the foreland of Lake Velence. Previous studies have already shown high uranium concentration values (compared to average crust values) related to the Velence Granite Formation in Velence Hills and to the carbonatic and organic-rich beds of the Ujfalu Formation in the foreland of Lake Velence. Until recently no observations and measurements were made regarding the radioactivity of the groundwater. Therefore, uranium, radium, and radon concentration measurements were carried out in the adjacent area and interpreted in flow system context. A total of 53 samples were taken from surface water as well as from groundwater. Alpha spectrometry applied on Nucfilm discs was used to measure the uranium (U-234, U-238) and radium (Ra-226) activity while radon (Rn-222) activity was determined by TriCarb 1000 TR liquid scintillation detection. Pressure-elevation profiles, hydraulic cross-sections, tomographic potential maps were compiled to understand the groundwater flow directions and regime characteristics in the wider area. The areal distribution of the activity concentration values was interpreted regarding the groundwater flow system, physicochemical parameters measured onsite and in the laboratory. Those areas can be delineated where according to the flow conditions and the related geochemical environment the mobility of the uranium or radium and thus elevated activity concentration can be expected in groundwater. The results of the study have proved that the areal variability of the natural radioactivity of the groundwater is strongly affected by the groundwater flow conditions along with geological features. This flow system approach and its methodology may facilitate the safe water management of drinking water supply systems.

This study was supported by the ÚNKP-17-4 and ÚNKP-18-3 New National Excellence Program of the Ministry of Human Capacities and it has also received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 810980.

 

How to cite: Baják, P., Csondor, K., Surbeck, H., Izsák, B., Vargha, M., Horváth, Á., Pándics, T., and Erőss, A.: How can flow system approach help to understand the natural radionuclide content of the drinking water originated from groundwater sources? Case study in the vicinity of a granitic complex, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1181, https://doi.org/10.5194/egusphere-egu2020-1181, 2020.

EGU2020-19757 | Displays | GI6.1

Atmospheric radioactivity measurements at the SMEAR Estonia Station

Heikki Junninen, Jussi Paatero, Urmas Hõrrak, and Xuemeng Chen

The SMEAR Estonia is a Station for Measuring Ecosystem-Atmosphere Relations (SMEAR). It is built on the same concept as the Finnish SMEAR stations [1] and belongs to the same measurement network. It is located in a hemiboreal forest at Järvselja, South-Eastern Estonia (58.2714 N, 27.2703 E at 36 m a.s.l.) [2]. The Estonian University of Life Sciences runs long-term measurements on meteorological parameters, trace gases and fluxes at the station. Atmospheric aerosol and air ions measurements are deployed by the University of Tartu (UT). 

 

Our main interest at UT lies in characterising atmospheric ions and aerosols, studying their connections to atmospheric new particle formation and cloud processes, and understanding the impacts of these processes on air quality, local weather and climate. Air ions are known to participate in forming atmospheric new particles [3]. Newly formed aerosol particles have the potential to modify cloud properties, once they reach big enough sizes via condensational and coagulational growth[4]. Air ions are primarily produced by the ionisation of air molecules, with the ionisation energy provided by natural radioactivity present in the atmosphere. The initial ionisation produces are subject to different dynamic processes, including charge transfer, clustering, coagulation and condensational growth [5]. At UT, we are launching a five-year project, starting from Jan. 2020, to investigate how atmosphere transforms the new-born air ions to climatically relevant aerosol particles. In order to get insights into the transformation process, atmospheric radioactivity measurements are crucial together with air ion and aerosol measurements.

 

In the lower troposphere, ionization of the atmospheric originates from the decay of radon and other radioactive nuclides in the air and the Earth's crust as well as cosmic radiation. In collaboration with the Finnish Meteorological Institute, we initiated atmospheric radioactivity measurements at the SMEAR Estonia. The total gamma radiation (50 keV to 1.3 MeV) is measured with a gamma radiation meter (RADOS RD-02L) (since June 2019). The atmospheric radon is monitored using a filter-based Geiger-Müller counter (since Nov. 2019), which is a one-counter variation of an earlier design[6]. Atmospheric radon concentration is determined based on deposited beta activity. Preliminary results show that SMEAR Estonia (mean gamma dose rate = 0.03 uSv/h, mean radon conc. = 2.5 Bq/m3) has less ionization than SMEAR II station in Finland (mean gamma dose rate = 0.08 uSv/h, mean radon conc. = 2 Bq/m3). The linkage of this observation to air ion properties is under progress.

References:

[1]       Hari P., Kulmala M., Boreal Environ. Res. 2005, 10, 315-322.

[2]       Noe S. M. et al., Forestry Studies 2015, 63.

[3]       Tammet H. et al., Atmospheric Research 2014, 135-136, 263-273.

[4]       Merikanto J. et al., Atmos. Chem. Phys. 2009, 9, 8601-8616.

[5]       Chen X. et al. Atmos. Chem. Phys. 2016, 16, 14297-14315.

[6]       Paatero J. et al., Radiat. Prot. Dosim. 1994, 54, 33-39.

How to cite: Junninen, H., Paatero, J., Hõrrak, U., and Chen, X.: Atmospheric radioactivity measurements at the SMEAR Estonia Station, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19757, https://doi.org/10.5194/egusphere-egu2020-19757, 2020.

EGU2020-17988 | Displays | GI6.1 | Highlight

Activation of the human body exposed to high radon activity

Viktor Golias

Radon is newly considered a risk factor for lung cancer. Traditionally, radon is used as a curative in spa. One way of balneation is radon inhalation in mines (eg Bad Gastein in Austria and Boulder mine in USA), where patients are exposed for several tens of minutes to hours to air activity in the order 10^3 to 10^4 Bq m-3 222Rn. Even higher activities can be found in abandoned uranium mines, often in the order 10^4 to 10^5 Bq m-3 222Rn in the poorly ventilated parts. These underground spaces are often visited by mineral collectors and montanists. In two abandoned uranium mines, the progression of surface beta activity of hair during the stay was monitored and the value and shape of the gamma dose-rate field was measured immediately after mine leaving.

Beta activity increases irregularly, due to the walking between areas with a different radon activity. The highest surface beta activity of hairs was at the end of the stay, with a maximum of 320 Bq cm-2. After leaving the mine, activity decreases exponentially with an effective half-life of about half an hour. Gamma activity was measured after a two-hour stay in an environment with radon activities ranging from 3.7*10^4 to 2.3*10^5 Bq m-3. The gamma field has the shape of a human figure. Especially the lungs and abdominal fat showed increased gamma. The highest gamma dose-rate was measured on hairs, up to 9 µGy h-1. Thus, a combination of surface activation, Rn-product deposition in the lungs, and dissolution of radon in the blood and its redistribution in the body were observed.

How to cite: Golias, V.: Activation of the human body exposed to high radon activity, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17988, https://doi.org/10.5194/egusphere-egu2020-17988, 2020.

EGU2020-7978 | Displays | GI6.1

A new comparative scale between tropopause height and beryllium 7 and the weight of quasi-biennial oscillation (QBO) effect.

Lucrezia Terzi, Gerhard Wotawa, Paul W. Staten, Lan Luan, Axel Gabriel, and Martin Kalinowski

Recent studies demonstrated how accurate beryllium 7 can be used as proxy to predict seasonal weather, in particular Indian monsoons, climate change patterns such as tropopause height changes, tropopause breathing and Jet Stream stalling.

Beryllium 7 studies also prove that climate change phenomena are not driven by solar flux or earth magnetic field but are only partially influenced by them.

In this work we will compare recent tropopause height data with Beryllium 7 in order to build a comparative scale between the 2 parameters, including a focus on QBO (quasi-biennual oscillation) to quantify the effect of QBO on the analysed beryllium 7 data.

How to cite: Terzi, L., Wotawa, G., Staten, P. W., Luan, L., Gabriel, A., and Kalinowski, M.: A new comparative scale between tropopause height and beryllium 7 and the weight of quasi-biennial oscillation (QBO) effect., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7978, https://doi.org/10.5194/egusphere-egu2020-7978, 2020.

EGU2020-14940 | Displays | GI6.1

Lessons learned on atmospheric radon modelling by statistical model-to-data comparison on gamma dose rate peaks

Arnaud Quérel, Denis Quélo, Thierry Doursout, and Claire Gréau

Radon-222 is a progeny of Uranium-238, naturally present in the Earth’s crust. After its migration through the soil, it reaches the atmosphere. The Radon progenies are then adsorbated to aerosol particles. The particles are scavenged by falling rain drops, leading a large amount of radon progenies to the ground. This sudden addition of radon progenies explains to the gamma dose rate peaks occurring during rainfall events.

An atmospheric radon modelling chain was developed. It is based on the IRSN long-range atmospheric transport modelling, and can be used to forecast or to reanalyze these events. The peaks are observed hundreds times a year on radioactivity monitoring networks in France. Then, a comprehensive statistical comparison can be achieved to evaluate the modelling, in particular its atmospheric transport component.

Less than half of the gamma dose rate peaks simulated matches the observed ones. We considered false positive – peaks simulated but not observed – and false negative – peaks observed but not simulated. Radon exhalation spatial distribution and seasons seem to have a major impact on the model capability to reproduce these peaks. The choice of rain data is also essential for a better simulation.

Beyond other validation cases, IRSN now has a validation tool, the database of which is populating on a daily basis, to evaluate the long-range atmospheric transport model used for emergency purposes. The quality of this response is a critical issue and has to be constantly improved. The statistics on the gamma dose rate peaks will improve our understanding of the phenomena. It will also be used to validate the improvement made on the accuracy of the radon exhalation spatial distribution.

How to cite: Quérel, A., Quélo, D., Doursout, T., and Gréau, C.: Lessons learned on atmospheric radon modelling by statistical model-to-data comparison on gamma dose rate peaks, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14940, https://doi.org/10.5194/egusphere-egu2020-14940, 2020.

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