bluuebunny/crossref_metadata_2025 huggingface dataset:
Seeing Helios electron data through the eyes of Solar Orbiter: modelling the angular response of EPD/EPT and its application to the full inversion of Helios events
Authors: Pacheco Daniel , Aran Angels , Gomez-Herrero Raul , Agueda Neus , Lario David , Heber Bernd , Sanahuja Blai , Wijsen Nicolas , Wimmer-Schweingruber Robert F.
Published: March 2020

The pitch-angle distribution of electron intensities is an essential piece of information in order to understand the transport processes undergone by the particles in their journey from their acceleration sites to the spacecraft and, to infer properties of the particle sources such as their intensity and duration.

In a previous work, we modelled fifteen solar relativistic electron events observed at different heliocentric radial distances by the Helios spacecraft (Pacheco et al. 2019). We used a Monte-Carlo transport model and an inversion procedure to fit the in-situ observations, and inferred both the electron mean free path in the interplanetary space and the injection histories of the electrons at two solar radii from the Sun. We applied a full inversion procedure, that is, we considered both the angular and the energetic responses of the Helios/E6 particle experiment in the modelling of the electron events.

By using the same methodology as previously employed for ACE/EPAM, STEREO/SEPT and Helios/E6 instruments, we have modelled the angular response of the Electron Proton Telescope (EPT) of the Energetic Particle Detector (EPD) on board Solar Orbiter. Here, we present the study of the modelled angular response and its application to several of the solar energetic particle (SEP) events previously modelled as if Solar Orbiter were located at the Helios position. We compare the pitch-angle distributions measured by Solar Orbiter and Helios at different phases of the intensity-time profile of the SEP events, that is, near the particle onset, peak and on the decay of the event, and for different interplanetary magnetic field orientations provided by the Helios measurements.

We found that despite Helios were spinning spacecraft which gathered electron information from eight angular sectors, the four Solar Orbiter/EPD/EPT fields of view will often offer similar angular coverage. We also found that, under specific circumstances, EPT can obtain better pitch angle distribution information than Helios, specifically when the interplanetary magnetic field points away from the ecliptic.

We expect, then, that Solar Orbiter will provide us with numerous and valuable observations that will permit us to untangle the transport effects that electrons, protons and ions suffer in their journey through interplanetary space.
LESS: Large-scale remote sensing data and image simulation framework over Vegetated Areas
Authors: Qi Jianbo , Xie Donghui
Published: March 2020

Three-dimensional (3D) radiative transfer (RT) modeling and simulation of the transport of radiation through earth surfaces is a challenging and difficult task. The difficulties lie in the complexity of the landscapes and also the intensive computational cost of 3D RT simulations. Current models usually work with abstract landscape elements to reduce complexity or only consider relatively small realistic scenes. In this study, a new 3D RT modeling framework (called LESS) is proposed. It employs a forward photon tracing method to simulate bidirectional reflectance factor (BRF) or flux-related data (e.g., downwelling radiation) and a backward path tracing method to generate sensor images (e.g., fisheye images) or large-scale (e.g. 1 km2) spectral images from visible to thermal infrared band. In this framework, a graphic user interface (GUI) and a set of tools are also provided to help to construct the landscape and set parameters, e.g., extracting tree crowns from airborne LiDAR data, which makes it more accessible to common users. The accuracy of LESS is evaluated with other models and field measurements in terms of directional BRF and pixel-wise comparisons. It shows that the accuracy of LESS is consistent with the reference models from RAMI model inter-comparison website (http://rami-benchmark.jrc.ec.europa.eu/HTML/Home.php) as well as field measurements. LESS has also been extended to simulate atmosphere, LiDAR and in-situ sensors. It provides as a useful tool for studying the radiative transfer process over complex forest canopies from leaf to canopy scales. The simulated datasets can be used as benchmarks for validating other physical remote sensing inversion algorithm and developing parameterized models for retrieving bio-geophysical variables of canopy. LESS can be accessed from http://lessrt.org.
Drought and heat-stress mortality risks: Assessing the role of climate change, socioeconomic vulnerabilities, and population growth
Authors: Ahmadalipour Ali , Moradkhani Hamid
Published: March 2020

Drought risk refers to the potential losses imposed by a drought event, and it is generally characterized as a function of vulnerability, hazard, and exposure. Here, we assess drought risk at a national level across Africa by considering climate change, population growth, and socioeconomic vulnerabilities. Drought vulnerability is quantified using a rigorous multi-dimensional framework based on 28 factors from six different sectors of economy, energy and infrastructure, health, land use, society, and water resources. Various analyses are conducted to assess the reliability and accuracy of the proposed drought vulnerability index (DVI). A multi-model and multi-scenario framework is employed to quantify drought hazard using a multitude of regional climate models. Drought risk is then assessed for 2 climate emission pathways (RCP4.5 and RCP8.5), 3 population scenarios, and 3 future vulnerability scenarios in each country during 2010-2100. Drought risk ratio is calculated for each scenario, and the role of each component (i.e. hazard, vulnerability, and exposure) is identified, and the associated uncertainties are also characterized. Results show that drought risk is expected to increase in future across Africa with varied rates for different models and scenarios. Although northern African countries indicate aggravating drought hazard, drought risk ratio is found to be highest in central African countries as a consequent of unprecedented vulnerability and population rise in the region. Results indicate that controlling the population growth is imperative for mitigating drought risk since it improves socioeconomic vulnerability and reduces potential exposure to drought. Meanwhile, climate change will considerably exacerbate drought and heat-stress hazards. Our findings show that global warming will escalate heat-stress mortality risk across Central Africa to unprecedented levels. It is revealed that unfortunately, the poorest countries (that have least contribution to climate change) are expected to be most impacted, and they will experience markedly higher risk ratios compared to the wealthier nations.
Novel 3D imaging of root systems grown in slab-shaped rhizotrons
Authors: Bereswill Sarah , Rudolph-Mohr Nicole , Tötzke Christian , Kardjilov Nikolay , Hilger André , Oswald Sascha
Published: March 2020

Complex plant-soil interactions can be visualized and quantified by combined application of different non-invasive imaging techniques. Oxygen, carbon dioxide and pH gradients in the rhizosphere can be observed with fluorescent planar optodes, while neutron radiography detects small-scale heterogeneities in soil moisture and its dynamics. Respiration and exudation rates can vary between roots of different types, such as primary and lateral roots, as well as along single roots among the same plant. The 3D root system architecture is therefore a key information when studying rhizosphere processes. It can be captured in detail with neutron tomography, but so far only for plants grown in small, cylindrical containers.

Combined non-invasive imaging of biogeochemical dynamics, soil moisture distribution and 3D root system architecture is a technical challenge. Thin, slab-shaped rhizotrons with relatively large vertical and lateral extension are well suited for optical fluorescence imaging, allowing for spatially extended observation of biogeochemical patterns. This rhizotron geometry is, however, unfavorable for standard 3D tomography due to reconstruction artefacts triggered by insufficient neutron transmission when the long side of the sample is aligned parallel to the beam direction.

We therefore applied neutron laminography, a method where the rotational axis is tilted, to measure the root systems of maize and lupine plants grown in slab-shaped glass rhizotrons (length = 150 mm, width = 150 mm, depth = 15 mm) in 3D. In parallel, we investigated rhizosphere oxygen dynamics and pH value via fluorescence imaging and assessed soil moisture distribution with neutron radiography.

Neutron laminography enabled the 3D reconstruction of the root systems with a nominal spatial resolution of 100 µm/pixel. Reconstruction quality strongly depended on root-soil contrast and hence soil moisture level. After reconstruction of the root system and co-registration with the fluorescence images, first results indicate that observed oxygen concentrations and pH gradients depend on root type and individual distance of the roots from the planar optode.

In conclusion, neutron laminography is a novel 3D imaging method for root-soil systems grown in slab-shaped rhizotrons. The method allows for determining the precise 3D position of individual roots within the rhizotron and can be combined with 2D imaging approaches. Following experiments will address X-ray laminography as a possible attractive further application.
Along-track analysis of GRACE and GRACE Follow-On KBR and LRI data for new science applications
Authors: Han Shin-Chan , Ghobadi Far Khosro , Sauber Jeanne , Mccullough Christopher , Wiese David , Landerer Felix
Published: March 2020

We present a method of analysing inter-satellite tracking data for detecting short-term (sub-monthly) gravitational changes from GRACE and GRACE Follow-On.  The method is based on the residual range-rate data with respect to the reference range-rate computed with dynamic orbital state vectors.  Then, we apply a numerical differentiation to compute range-acceleration residuals.  We found that the range-acceleration residuals are near-perfectly correlated with the line-of-sight gravity difference (LGD) between two spacecrafts and the transfer (admittance) function between them can be determined regardless of time and space (Ghobadi-Far et al., 2018, JGR-Solid Earth, https://doi.org/10.1029/2018JB016088).  The transfer function, to be applied directly to range-acceleration residuals, enables accurate LGD determination with the error of 0.15 nm/s^2 over the frequency band higher than 1 mHz (5 cycles-per-revolution), whereas the actual GRACE measurement error is several times larger.

In this presentation, we present two new geophysical applications to examine high-frequency gravitational changes at times scales of significantly less than one month; Gravitational observation of tsunamis triggered by the 2004 Sumatra, 2010 Maule, and 2011 Tohoku earthquakes and transient gravitational changes due to Earth’s free oscillation excited by the 2004 earthquake.  Lastly, we present new results from GRACE Follow-On KBR and LRI inter-satellite ranging data. 
Aeolian-fluvial sediments as palaeoenvironmental records in the eastern Qaidam Basin, NE Tibetan Plateau, since MIS6
Authors: Yu Lupeng , Greenbaum Noam , Roskin Joel
Published: March 2020

Aeolian sediments sensitively respond to climatic changes. Continuous Quaternary loess deposits plays important roles in palaeoclimatic reconstructions. However, application of aeolian sand for such reconstructions is limited by its discontinuous depositional nature. Aeolian-fluvial sediments are widely distributed in arid and semi-arid regions where dunefields interact with watercourses. These palaeoenvironmental archives have been sparsely studied mainly due to their mixed character that requires new interpretation approaches.

We have found that climate fluctuations lead good preservation of aeolian sand deposits that underlay fluvial sediments, making the sedimentary records more continuous. In this study, aeolian and fluvial sediments (elevation of 3400-3500 m a.s.l.) were studied in the eastern margin of Qaidam Basin (QB), northeastern Tibetan Plateau to reconstruct palaeoenvironmental and palaeoclimatic changes since the MIS6, based on sedimentary facies, 120 OSL ages (with age range of 143-1 ka), grain size distribution, MS, TOC, and carbonates.

Within a deeply (10-65 m) incised 1.5-km-long valley, aeolian-fluvial cycles displayed frequent dune-damming of a stream since MIS6. Dune sands were dated to MIS's 6, 5d, 4, 3c, 3a, and the last deglaciation, while fluvial and dune-dammed lake sediments were dated to MIS's 5c, 3c, 3a, and deglaciation.

Large-scale A-F interactions mainly occurred during MIS3 and deglaciation, when the QB dunefields were still mobile after LGM and MIS4 and precipitation started to increase. No ages fall within LGM, suggesting an extremely arid and windy environment in which the dune sand kept reworking and cannot record OSL ages. This further confirms that only with the covering of fluvial sediments, aeolian sand can be well preserved. On the other hand, OSL ages of aeolian sand might only present periods when aeolian activities were not too strong.

During the Holocene, loess-paleosol accumulated in the QB margins, with loess accumulation since 10 ka and development of paleosols during ca. 8.5-3 ka, the Holocene optimum. These results demonstrate that aeolian-fluvial sediments are important palaeoenvironmental records in arid region and indicate that the climate of the eastern QB was mainly controlled by the temperature (solar insolation) and precipitation (Asian Summer Monsoon) changes since MIS6.  
An Adaptive Prediction System for Specifying Solar Wind Conditions Near the Sun
Authors: Reiss Martin , MacNeice Peter , Muglach Karin , Arge Nick , Möstl Christian , Riley Pete , Hinterreiter Jürgen , Bailey Rachel , Weiss Andreas , Owens Mathew , Amerstorfer Tanja , Amerstorfer Ute
Published: March 2020

The ambient solar wind flows and fields influence the complex propagation dynamics of coronal mass ejections in the interplanetary medium and play an essential role in shaping Earth's space weather environment. A critical scientific goal in the space weather research and prediction community is to develop, implement and optimize numerical models for specifying the large-scale properties of solar wind conditions at the inner boundary of the heliospheric model domain. Here we present an adaptive prediction system that fuses information from in situ measurements of the solar wind into numerical models to better match the global solar wind model solutions near the Sun with prevailing physical conditions in the vicinity of Earth. In this way, we attempt to advance the predictive capabilities of well-established solar wind models such as the Wang-Sheeley-Arge model. We perform a statistical analysis of the resulting solar wind predictions for the years 2006 to 2015. The proposed prediction scheme improves all the coronal/heliospheric model combinations investigated by approximately 15-20 percent in terms of various comprehensive prediction validation measures. We discuss why this is the case, and conclude that our findings have important implications for future practice in applied space weather research and prediction.
Thirty-five million years of changing climate – carbon cycle dynamics
Authors: De Vleeschouwer David , Drury Anna Joy , Vahlenkamp Maximilian , Liebrand Diederik , Rochholz Fiona , Pälike Heiko
Published: March 2020

Fifty-one years of scientific ocean drilling through the International Ocean Discovery Program (IODP) and its predecessors generated a treasure trove of Cenozoic climate and carbon cycle dynamics. Yet, it remains unclear how climate system and carbon cycle interacted under changing geologic boundary conditions. Here, we present the carbon isotope (d13C) megasplice, documenting deep-ocean d13C evolution since 35 million years ago (Ma). We juxtapose the d13C megasplice with its d18O counterpart and determine their phase-difference on ~100-kyr eccentricity time-scales. This analysis uncovers that 2.4-Myr eccentricity modulates the in-phase relationship between d13C and d18O during the Oligo-Miocene (34-6 Ma), potentially related to changes in continental weathering. At 6 Ma, a striking switch from in-phase to anti-phase behaviour occurs, signalling a threshold in the climate system. We hypothesize that Arctic glaciation and the emergence of bipolar ice sheets enabled eccentricity to exert a major influence on the size of continental carbon reservoirs. Our results suggest that a reverse change in climate - carbon cycle interaction should be anticipated if CO2 levels rise further and we return to a world of unipolar ice sheets.
Development of a Low Cost Novel PT Logging Tool for High Temperature Operation (600°C)
Authors: Hamremoen Røed Morten
Published: March 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.

 
Proababilistic Approach to Deterministic Inundation Map Informed by Geographical Factors
Authors: Yu Jae-Ung , Jung Minkyu , Kim Jin-Young , Kwon Hyun-Han
Published: March 2020

Urbanization causes extension of impervious surface interrupting natural hydrological cycle, which may increase in the number of disaster factors causing difficulties in terms of flood management. Flood control measures should prioritize identification of areas where flooding is expected to occur, considering various spatial characteristics distributed over the areas at risk. In this study, a probabilistic flood risk assessment was performed. The flood hazard map for a 100-year return level was used to illustrate the concept of a probabilistic model. Here, we trained the model to obtain the relationship between the estimated inundation area and potential predictors such as elevation, slope, curve number, and distance to the river. In this study, a Bayesian logistic regression analysis was performed to impose probabilities on the inundation for each grid. Finally, the flood risk was provided with the population for the entire target area through the model.

 

Keywords: Bayesian Inference, Flood Hazard Map, Geographical Information, Logistic Regression

 

Acknowledgement

This work is supported by the Korea Agency for Infrastructure Technology Advancement(KAIA) grant funded by the Ministry of Land, Infrastructure and Transport (Grant 19AWMP-B121100-04)
Technical solutions for landslide risk mitigation with law impact on landscape
Authors: Volpe Evelina , Salciarini Diana , Cattoni Elisabetta
Published: March 2020

Landslide risk mitigation that takes into account the safeguarding of environmental landscape involves several technical difficulties. However, at present, it is fundamental to identify sustainable technical and ￼economic solutions in order to preserve the Italian areas characterized by an undoubted landscape and environmental heritage.

In most cases, landscape is deeply and destructively hit both when a landslide occurs, both when countermeasures for its mitigation are taken. Indeed, traditional technical solutions to increase slope safety are often costly and very impacting on natural environment and landscape. A possible alternative for improving slope stability is based on the use of non-invasive naturalistic engineering techniques [1]. Such solutions have a low impact on landscape and natural environment, conserving landscape identity and characteristics. Unfortunately, nowadays the use of these solutions is limited, since they suffer of a lack of rational approaches that quantify their stabilizing action. To overcome such constraint, we carried out a numerical study to evaluate the efficiency of remedial works based on naturalistic engineering to improve slope stability, considering a wide range of ideal slopes and different combinations of pre- and post- conditions (geometry, materials, types of soil protection solutions, etc.). As shown by the results of the stability analyses, in all the cases considered, the adopted naturalistic engineering techniques are able to increase the level of safety of the slopes with a very limited impact on the natural environment and landscape, due to the use of natural materials for the construction.

In this work we present a summary of the main techniques adopted in the field of naturalistic engineering. After introducing the methods generally used in evaluating the slope stability, the role played by vegetation in the mitigation of hydrogeological instability will be presented, with particular reference to the mechanical effect exerted by the plant roots which typically increases the soil shear strength. Then, the numerical study carried out to quantify the stabilizing effects deriving from the presence of vegetation will be shown, together with the main results obtained. Finally design indications for the application of non-invasive reinforcement techniques are presented.

 

Acknowledgements: The activities by the second Author have been carried out thanks to the PRIN2015 project "Innovative Monitoring and Design Strategies for Sustainable Landslide Risck Mitigation".
A multi-frequency Celestial Reference Frame at S/X, K and X/Ka-band
Authors: Karbon Maria , Nothnagel Axel
Published: March 2020

We present a Celestial Reference Frame (CRF) based on the combination of independent, multi-frequency radio source position catalogs using nearly 40 years of Very Long Baseline Interferometry observations at the standard geodetic frequencies at S/X band and about 15 years of observations at higher frequencies (K and X/Ka). The final catalog contains 4617 sources.

The novelty in our approach is the combination of independent, multi-frequency radio source position catalogs through a rigorous combination by carrying over the full co-variance information of each catalog through the process of accumulation of normal equation systems instead of using only the positions themselves. Through the novel process of combination, a complete co-variance matrix of the entire set of sources across the three bands is provided. Special validation routines were used to characterize the random and systematic errors between the input reference frames and the combined one.

The resulting CRF contains precise positions of 4617 compact radio astronomical objects, 4536 measured at 8~Ghz, 824 sources being observed also at 24 GHz and 674 at 32 GHz. The frame is aligned with ICRF3 within ±3 μas and shows an average positional uncertainty of 0.1 mas in right ascension and declination. No significant deformations can be identified. Comparisons with Gaia-CRF remain inconclusive, nonetheless significant differences between all frames can be attested.
Determining the speed of intracontinental subduction – preliminary results of zoned garnet geochronology in micaschists from the Schneeberg Complex, Eastern Alps.
Authors: Fassmer Kathrin , Tropper Peter , Pomella Hannah , Angerer Thomas , Degenhard Gerald , Hauzenberger Christoph , Münker Carsten , Schmitt Axel K. , Fügenschuh Bernhard
Published: March 2020

In collisional orogens continental crust is subducted to (ultra-)high-pressure (HP/UHP) conditions as constrained by petrologic, tectonic and geophysical observations. These (U)HP rocks are exhumed by an extremely fast process (few Ma) as numerous rocks still preserve their high-pressure metamorphic assemblages, which would not be the case if they had time to re-equilibrate at lower pressure conditions. Despite a wealth of studies on the subduction and exhumation of UHP rocks, the duration of prograde metamorphism during subduction is still not well constrained.

We plan to do Lu-Hf and Sm-Nd geochronology on metamorphic rock samples to date the duration of garnet growth, which represents a major part of prograde metamorphism from the greenschist-facies on. Micaschist samples from the Schneeberg and Radenthein Units in the Eoalpine high-pressure belt (Eastern Alps) will be used for dating as they contain cm- to dm-sized garnets, which experienced only one subduction-exhumation cycle with P-T conditions reaching 600 °C and up to 1 GPa. With dating different parts of big garnet grains we test (1) if it is possible to resolve the duration of garnet growth within single crystals, (2) if both systems, Lu-Hf and Sm-Nd, are needed for better age-constraints, and (3) whether both systems date the same events in the PT-path or give differing information. Additionally we will perform U-Pb geochronology on titanite in order to obtain the age of the first stages of exhumation and on rutile inclusions as well as matrix rutiles to confirm the Eoalpine prograde age with this additional method. Therefore, we will be able to compare the duration of subduction and the timing of initial exhumation in a single sample. We then will constrain the PT-path of the samples that will be dated by pseudosection modeling combined with Zr-in-rutile geothermometer, quartz-in-garnet geobarometer, and carbonaceous material geothermometer. In addition EPMA, µ-XRF, LA-ICPMS, and µCT will be used to control if garnets preserved major and trace elemental growth zoning and to provide spatial 3D information on inclusion patterns. With dating different parts of single garnet crystals separately with Lu-Hf and Sm-Nd geochronology, we will add tight time constraints to the PT-path and constrain the duration of garnet growth.

With this contribution we formulate the working hypothesis that prograde subduction together with  exhumation is a fast process. The basis for testing the idea of fast prograde metamorphism is that many geochronological studies propose a prograde duration of < 10 Ma and studies using geospeedometry sometimes propose an even shorter duration, which is the impetus for this investigation.
Geochemistry and isotope studies of the metavolcanic rocks of Shimoga greenstone belt, Western Dharwar craton - an effort to deduce the Petrogenesis.
Authors: Giri Anshuman , Anand Rajagopal
Published: March 2020

The archaean greenstone belts, dominated by mafic to felsic volcanic rocks followed by younger granitic intrusions occurs associated with volcano-sedimentary sequences. The Dharwar Super group (2600 to 2900 Ma) of rocks in western Dharwar craton, underlie the older TTG gneisses. The Shimoga greenstone belt (SGB) of WDC constitute the basal polymictic conglomerate along with quartzite, pyroclastic rocks, carbonaceous rocks, greywacke-argillite sequences with a thick pile of mafic and felsic metavolcanic rocks (BADR). These rocks are suffered from greenschist to lower amphibolite grade of metamorphism. The Medur metavolcanic volcanic rocks give an age of 2638 ± 66 Ma (1), whereas the Daginakatte felsic volcanic rocks give an age of 2601 ± 6 Ma (2). The present studied age of 2638 ± 66 Ma, tells about the cessation of mafic magmatism in WDC. The metavolcanic rocks of the Medur formation are tholeiitic to calc-alkaline in nature. These rocks show flat to LREE enriched REE pattern with negative europium anomaly. And also show enrichment in LILE and depletion in HFSE elements with significant Nb-Ta anomaly. The geochemical and the isotope data suggest the involvement of partial melting of the depleted mantle by the slab components and assimilation fractional crystallization (AFC) processes for the magma generation. The SGB metavolcanic rocks have 143Nd/144Nd ratios (0.511150 to .513076) and εNd values of -3.1 to -5.5 and the negative εNd values  for the rocks is due to the crustal contamination of the magma in a shallow marine subduction setting. The parental magmas were derived from melting in the mantle wedge fluxed by slab derived fluids and slab components followed by assimilation fractional crystallization (AFC) processes involving continental crust in an active continental margin.

(1) Giri et al., 2019. Lithos, 330-331, 177-193

(2) Trendall et al., 1997a. J. Geol. Soc. India, 50, 25-50.
Presentation and methodology of TRANSKARST project
Authors: Boudon Arthur , Celle-Jeanton Hélène , Bertrand Xavier , Albaric Julie , Amiotte-Suchet Philippe , Choulet Flavien , Crini Nadia , Hocquet Didier , Huneau Frédéric , Le Coustumer Philippe , Loup Christophe , Mathieu Olivier , Miege Cécile , Stefani Vanessa , Steinmann Marc , Sue Christian , Thevenot Mathieu , Trap Pierre
Published: March 2020

TRANSKARST is an interdisciplinary research project with scientists and regional water resource administrators. This 3 years project (2019-2022) is set up on Arcier's karstic watershed used for the drinking water supply of 60 000 inhabitants of Besançon, France. Using this instrumental basin, as a part of Jurassic Karst French observation system, the project aims at defining pathways of mineral, organic and microbiological contamination in karstic system.

The methodology used in the project, combines field expertise with the implementation of analytical tools related to conventional - dissolved phase chemistry (major ions, miners, traces, organic carbon), isotopes (oxygen-18, deuterium, carbon-13) – and prospective analysis - emerging pollutants such as pharmaceuticals and ETM, dissolved organic matter, suspended matter and microbiology (bacteria, fungal species) with a special focus on antibiotic resistance. The TRANSKARST project thus brings together a consortium of researchers from various disciplines: hydrogeology, chemistry, sedimentology, microbiology, geology and geophysic. The project is also highly associated to water managers as Arcier’s spring is used for drinking water supply.

The three main under-objectives following by TRANSKARST could be summarized as follows. First, through geological and geophysical investigation, a conceptual and numerical geological model will be established under geomodeler and will be further used to constrain the pathways of karstic groundwater. The second point focus on the evaluation of karst media contamination: chemical (including emerging molecules) and microbiological. Then we expect to discriminate, by the use of ETM, dissolved, colloidal and particulate pathways of contamination. All the observations will be linked together to identify actions and feedback of different parameters and contaminants within karst hydrosystems.
Mechanical interactions between pressure sources and rift zones at Kilauea Volcano, Hawaii.
Authors: Pulvirenti Fabio , Aloisi Marco , Carbone Daniele , Poland Michael , Vinciguerra Sergio
Published: March 2020

Underground pressure sources and rift zones may act jointly during phases of volcanic activity. Pressurization of magma bodies at shallow to intermediate depth, along with degradation of the mechanical properties of the host rock, can enhance tensile stress along zones of weakness, thus favoring magma intrusion. Such interactions were hypothesized at different volcanoes, including Mt. Etna, Piton de la Fournaise and Montserrat, from seismic, gravity and ground deformation data. Here we use a finite-element modeling approach to quantitatively understand possible mechanical interactions between a shallow pressure source beneath the summit caldera and the rift zones at Kīlauea Volcano (Hawai‘i). Past studies have demonstrated a strong connection between these structures, for example, with increases in seismic activity and extension across the rift, during phases of inflation of the summit. These observations suggest a coupling, which may modulate magma accumulation and transport processes along the rift.
Preliminary study of Compound Events in Greece using high-resolution downscaled climate data
Authors: Sfetsos Athanasios , Markantonis Jason , Karozis Stylianos , Politi Nadia , Vlachogiannis Diamando
Published: March 2020

Climate change is set to result in an increase of extreme weather events such as extreme precipitation, heatwaves, floods, droughts etc. The study of the possibility of the increase of such events is of high importance, but equally important is to study the combination of these events, meaning the study of Compound Events. In our case we focus on the combination of extreme precipitation with extreme wind speed for the region of Greece.

Greece located in the region of the Eastern Mediterranean Sea is prone to Climate Change as the whole region of the Mediterranean Basin. So, it is crucial to understand how the country is affected by Compound Events of extreme precipitation and extreme wind speed. As a first step, we study the historic period 1980-2009 using the model output data. The data for the historic period analysis have been produced from Weather Research Forecast (WRF) 5km downscaled model output with temporal resolution of 6 hours, using as input ERAINTERIM data. The downscaling study that has produced the atmospheric model dataset is described in Politi, et al. (2018). The methodology for studying Compound Events in the area is presented together with the preliminary results. 
NetCDF: Performance and Storage Optimization of Meteorological Data
Authors: Kivachuk Burdá Valentín , Zamo Michaël
Published: March 2020

Any software relies on data, and the meteorological field is not an exception. The importance of using correct and accurate data is as important as using it efficiently. GRIB and NetCDF are the most popular file formats used in Meteorology, being able to store exactly the same data in any of them. However, they differ in how they internally treat the data, and transforming from GRIB (a simpler file format) to NetCDF is not enough to ensure the best efficiency for final applications.

In this study, we improved the performance and storage of ARPEGE cloud cover forecasts post-processing with convolutional neural network and Precipitation Nowcasting using Deep Neural Network projects (proposed in other sessions for the EGU general assembly). The data treatments of both projects were studied and different NetCDF capabilities were applied in order to obtain significantly faster execution times (up to 60 times faster) and more efficient space usage.
Modelling 2018 Anak Krakatoa flank collapse and tsunami – effect of landslide failure mechanism and dynamics on tsunami generation
Authors: Zengaffinen Thomas , Løvholt Finn , Pedersen Geir
Published: March 2020

The 2018 Anak Krakatoa volcano flank collapse and tsunami caused several hundred fatalities. There was no early warning system in place for the landslide triggered tsunami, and there is a lack in understanding on how the failure mechanism affected landslide dynamics and tsunami generation, which we focus on in this study. While researchers previously have modelled the collapse as an instantaneous release, we here illuminate how different landslide failure scenarios, including a gradually released flank failure, influence the tsunami generation. We simulate the material movement by using a viscoplastic flow model with Herschel-Bulkley rheology and we employ a depth-averaged model to both the landslide and the tsunami propagation. A sensitivity study to the gradual mass release, total release volume, the material yield strength, the remoulding coefficient, and landslide directivity is used to shed light on the tsunami generation. Our analysis indicates that an instantaneous mass release in 125 degree SW direction fits the observed waveforms at coastal gauge stations best. In our simulations, we observe, as many other authors, discrepancies between simulated and observed arrival times and wave periods offshore Sumatra. Hence, we have also investigated sensitivity to the bathymetric depth by varying the water depth in areas near the source. Finally, we simulate the tsunami inundation at two coastal sites in southwestern Java using open-source topographic data. Given the limitations in the topographic data, a reasonably good agreement between the simulations and observations are obtained.
High-resolution measurements of plasma entry into the polar cap: indication of plasma structuring
Authors: Jin Yaqi , Spicher Andres , Ivarsen Magnus , Moen Jøran , Clausen Lasse
Published: March 2020

Polar cap patches/tongue of ionization are believed to be the dominant space weather phenomena in the high-latitude ionosphere as they are associated with significant plasma irregularities. These irregularities can greatly degrade satellite-based communication and navigation systems that rely on trans-ionospheric signals. Due to the practical need for a more reliable space weather forecasting system, the plasma structuring of these phenomena are an active area of research in recent years. In the study, we present a case of a tongue of ionization that was formed due to the transport of the high-density plasma from the dayside sunlit ionosphere into the dark polar cap. The tongue of ionization was probed by the first Norwegian scientific satellite NorSat-1 in noon-midnight orbits. Among other payloads, NorSat-1 carries the multi-needle Langmuir probe (m-NLP) system that is capable of measuring electron density at a rate up to 1 kHz. The electron density measurement shows significant irregularities at all scales along the profile of the tongue of ionization. In the dayside auroral oval, the electron density is associated with clear mesoscale (20-80 km) density enhancements, which are likely caused by structured auroral precipitations. We also use data from other satellites (e.g., Swarm and DMSP) to support observations from NorSat-1.
Investigation of the characteristics of the Soil by means of TDR probes: preliminary work and future perspectives
Authors: Farrugia Lourdes , Farhat Iman , Persico Raffaele , Sammut Charles
Published: March 2020

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.
Local seismicity near the actively deforming Corbetti volcano in the Main Ethiopian Rift
Authors: Keir Derek , Lavayssiere Aude , Greenfield Tim , Kendall Mike , Ayele Atalay
Published: March 2020

Corbetti is currently one of the fastest uplifting volcanoes globally, with strong evidence from geodetic and gravity data for a subsurface inflating magma body. A dense network of 18 stations has been deployed around Corbetti and Hawassa calderas between February 2016 and October 2017, to place seismic constraints on the magmatic, hydrothermal and fault slip processes occurring around this deforming volcano. We locate 122 events of magnitudes between 0.4 and 4.2 were located using a new local velocity model. The seismicity is focused in two areas: directly beneath Corbetti caldera and beneath the east shore of Lake Hawassa. The shallower 0-5km depth below sea level (b.s.l.) earthquakes beneath Corbetti are mainly focused in NW-elongated clusters at Urji and Chabbi volcanic centres. This distribution is interpreted to be mainly controlled by a northward propagation of hydrothermal fluids from a cross-rift pre-existing fault. Source mechanisms are predominantly strike-slip and different to the normal faulting away from the volcano, suggesting a local rotation of the stress-field. These observations, along with a low Vp/Vs ratio, are consistent with the inflation of a gas-rich sill, likely of silicic composition, beneath Urji. In contrast, the seismicity beneath the east shore of Lake Hawassa extends to greater depth (16 km b.s.l.). These earthquakes are focused on 8-10 km long segmented faults, which are active in seismic swarms. One of these swarms, in August 2016, is focused between 5 and 16 km depth b.s.l. along a steep normal fault beneath the city of Hawassa, highlighting the tectonic hazard for the local population.
Run4Life project: A step forward in NPK recovery from source-separated wastewaters.
Authors: Torres Sallan Gemma , Borras Eduard , Aliaguilla Martí , Molognoni Daniele , Sanchis Sonia , van-Eekert Miriam , Moerland Merjin , Todt Daniel , Chatzopoulos Paraschos , Meulman Brendo , Kjerstadius Hamse , Demolder Lieven , de-Smet Peter , Morales Nicolas
Published: March 2020

Domestic wastewater (WW) is an important carrier of nutrients usually wasted away by current centralised sewage treatment plants. The Run4Life project proposes an alternative strategy for increasing circularity of WW treatment systems and improving nutrient recovery rates and material qualities. This is based on a decentralised treatment of segregated black water (BW), kitchen waste and grey water combining existing and innovative technologies.

Run4Life is currently improving innovative nutrient recovery technologies, these being: (i) an ultra-low flush vacuum toilet, which uses around 0.5L/flush, thus less water than conventional vacuum toilets, allowing concentration of BW compared to conventional toilets and vacuum toilets. (ii) Bio-electrochemical systems for nitrogen recovery, which recovers up to 12.8 g/m2*d of Nitrogen present in blackwater as liquid fertilizer (ammonium nitrate) iii) (Hyper-)thermophilic anaerobic digestion, which aims to recover the phosphorous and nitrogen in the hygienised effluent in a one-step treatment and ready for use as fertilisers.  

Nutrient recycling technologies from domestic WW are demonstrated at large scale in four demonstration sites where decentralised WW treatment systems are implemented: Ghent (Belgium, 430 houses), Helsingborg (Sweden, 320 apartments), Sneek (The Netherlands, 32 houses), and Vigo (Spain, 1 office building). This will result in solid and liquid NPK fertilizers being recovered in the form of struvite, ammonium nitrate, calcium phosphate, organic fertilizers and reclaimed water.

The environmental, economic and societal impact of the obtained fertilizers is being tested by means of ecotoxicology tests, pot experiments, field trials, and by a selection of key performance indicators based on European, national and regional legislation present in the four different countries. Life cycle assessments are being performed for each technology and demonstration site, and active measures such as knowledge brokerage activities are being developed as an engagement strategy to advocate the institutional, legal and social acceptance of the Run4Life nutrient recovery technologies and fertilizers produced.  In addition, new business models which can benefit from the Run4Life project are currently being assessed.

It is expected that, by the end of the project, more than 90% of the water will be reused, and that nutrient recovery rates will achieve 100%.
Inventory of Good Agricultural Practices for climate resilience in Central America
Authors: Urquijo Reguera Julia , Postigo José Luis , Puigdueta Ivanka , Juarez Laura , Sánchez Jacob Eduardo , Ruiz Ramos Margarita , Hernández Díaz-Ambrona Carlos Gregorio , Rodríguez-Sinobas Leonor
Published: March 2020

Agricultural practices and technologies play a crucial role in the adaptation to climate change and disaster risk reduction, especially in contexts of high social and environmental vulnerability as in the Meso American Dry Corridor. This area, home to more than 40 million people and half of the smallholders basic grain farmers, is highly sensitive to El Niño phenomenon, associated to 30-40% decrease of precipitation and long periods of water shortages. This in turn makes agricultural production difficult to success and maintain subsistence livelihoods of the rural poor. Thus, adaptation to climate variability is key for sustainable development in the dry corridor.

In this study we develop a methodology to systematically review Good Agricultural Practices (GAP) for climate change adaptation and disaster risk reduction to gain a comprehensive overview of adaptation options that can guide policy recommendations at the local level. The food-water-energy nexus approach has been considered in this methodology.

The methodology starts analyzing good agricultural practices (GAP) already identified in the Meso American Dry Corridor documented by different types of actors (International organizations, NGOs, local and national governments, academia, private sector). They were classified in different agricultural subsectors (farming, livestock, agroforestry, forestry and fishing and aquaculture) regarding climate variability and several natural hazards such as drought and flood. Then, a live spread sheet database was developed where the best practices were organized following the criteria defined based on literature review and expert knowledge. These  criteria were established to assess each potential good practice taking into account agroecological adequacy, socioeconomic viability, increase in resilience and environmental co-benefits, and specific consideration to the water-energy nexus. Finally, a group of 145 GAP were identified for the region.

Most of the GAP correspond to crop production, and they are mostly related to drought management and coping with interannual climate variability. It is observed that GAP are frequently implemented as a combination of practices and techniques as well as to face several hazards at the same time. In this regard, the analysis of water resources and the energy component should be seen under the food-water-energy nexus approach to ensure that a complete assessment of a potential GAP.