bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluid driven seismic cycle modelling in subduction zones
Authors: Hegyi Betti , Gerya Taras , Dal Zilio Luca , Behr Whitney
Published: March 2024

The role of fluid flow in triggering earthquakes in subduction zones is a critical yet complex aspect in seismology. Despite extensive study through geological, geophysical observations, and laboratory experiments, fully understanding and modelling these processes within a coupled solid-fluid interaction framework remain challenging. This study employs a coupled seismo-hydro-mechanical code (i2elvisp) to simulate fluid-driven earthquake sequences in a simplified subduction megathrust environment. We incorporate non-uniform grid resolution, enhancing the resolution of seismic events within the subduction channel. The code integrates solid rock deformation with fluid dynamics, solving mass and momentum conservation equations for both phases, alongside gravity and temperature-dependent viscosity effects. Brittle/plastic deformation is modelled through a rate-dependent strength formulation, with slip instabilities governed by compaction-induced pore fluid pressurisation. Our approach demonstrates the significant impact of fluid pressurisation on deformation localization, achieving slip rates up to metres per second in a fully compressible poro-visco-elasto-plastic medium. By refining the vertical model resolution in the subduction channel to less than or equal to 200 metres, we ensure convergence in terms of event recurrence interval and slip velocity. The models successfully replicate various slip modes observed in nature, ranging from regular earthquakes (including partial and full ruptures) to transient slow slip phenomena and aseismic creep. This research focuses on the parameters influencing the dominant slip mode, their distributions, and interactions along a modelled subduction interface. Our findings indicate that the dominant slip mode and the earthquake sequences are significantly influenced by porosity, permeability, and temperature-dependent viscosity. We explore two distinct viscosity gradients in the subduction channel to represent subduction zones with differing thermal profiles. In 'hot' subduction models, the brittle-ductile transition commences at shallower depths than in 'cold' subduction cases, influencing the nucleation depth of seismic events. These viscosity variations markedly impact model evolution; regular earthquakes exhibit higher velocities and slip rates in 'hot' scenarios, which are also more conducive to hosting aseismic creep or slow slip events. In conclusion, our study elucidates the pivotal role of fluid pressure evolution in seismicity within subduction zones and provides deeper insights into earthquake source processes. Through comprehensive modelling and analysis, we enhance understanding of the complex dynamics governing fluid-induced seismic activity and contribute to the broader field of earthquake source processes. 
Urban and meteorological factors controlling transpiration dynamics of two common deciduous tree species in the city of Freiburg, Germany
Authors: Anys Markus , Weiler Markus
Published: March 2024

Urban hydrological processes are mainly influenced by anthropogenic activities, such as the expansion of impermeable surfaces which reduces infiltration of rainwater, increases runoff generation processes, and reduces evapotranspiration. Urban trees contribute positively to moving the urban water cycle closer to a natural one through their ecohydrological processes (e.g. transpiration). However, high heterogeneity within urban environments and increasing drought periods create multiple stressors to trees’ ecophysiology. We conducted intensive field measurements on Norway maple (Acer platanoides) and small-leaved lime (Tilia cordata) in the city of Freiburg, Germany, to advance our process understanding of transpiration behaviour of urban trees at contrasting growing and microclimatic environments and to determine the main hydrometeorological factors influencing transpiration. Soil water content, sap flux, crown solar radiation transmissivity, and meteorological measurements within the crown were carried out on 11 trees per species on sites with different degrees of surface sealing underneath tree crowns, in particular parks, parking lots, grass verges and tree pits.Throughout the investigation period (2021-2022), average daily transpiration rates during the growing season were higher for small-leaved lime (1.76 ± 0.53 mm) than for Norway maple (1.53 ± 0.51 mm). We observed significantly reduced daily transpiration rates (1.13 ± 0.31 mm) at tree planting sites (e.g. tree pits) with 90% impermeable surface underneath the tree crowns. On average, the main hydrometeorological drivers for day-to-day transpiration dynamics were solar radiation (39.7%), followed by vapour pressure deficit (22.4%), and soil water content (4.8%). Additionally, tree morphological traits, such as leaf area index (LAI) and leaf area density (LAD), as well as the degree of surface sealing affected transpiration significantly (p-value < 0.05) among sites. Furthermore, LAI is significantly correlated with the proportion of surface sealing within the crown projection area. With this study, we created a highly needed dataset for the main urban tree species in Central European cities and provided a solid knowledge base for transpiration processes of trees in various urban environments. The study revealed that long-term field measurements with multiple tree species under contrasting urban growing conditions are a necessity to quantify tree transpiration dynamics and their contribution to the urban water cycle and to the cooling potentials of urban trees. In addition, relevant factors to plan resilient urban ecosystems can be extracted with such datasets and analysis.
Atmospheric blocking and extreme weather frequency patterns associated with solar irradiance forcing during the last 400 years
Authors: Rimbu Norel , Spiegl Tobias , Lohmann Gerrit
Published: March 2024

Although the influence of Sun on climate variability is largely investigated its contribution to extreme weather and climate change remains widely questioned. Because the sample sizes of observed weather and climate extremes are typically too small, we used seasonal resolution paleo-reanalysis data as predictors to extend back in time the field of observed climate extreme indices to reliably identify the solar signal. We reconstructed the field of a two-dimensional atmospheric blocking frequency indicator in the North Atlantic region as well as the field of the frequency of extreme cold temperature and extremely high precipitation days over Europe back to the year 1600. Based on these reconstructions, we show that low (high) solar irradiance winters are associated with more (less) frequent blocking in the Atlantic-European region. This pattern was particularly strong during Maunder and Dalton solar minima. Consistent anomaly patterns are identified for the frequency of extreme low temperature and extremely high precipitation days over Europe. A numerical experiment reveals a significant increase in the blocking frequency in the Atlantic-European region during a Grand Solar Minimum relative to the 1850s solar irradiance levels. This suggests that blocking anomaly patterns associated with total solar irradiance forcing during winter, as derived from observational data, are robust in the perspective of the last four hundred years of blocking and associated weather extreme variability in the North Atlantic region. Therefore, these patterns are useful to estimate the blocking and related weather extremes under various scenarios/predictions of total solar irradiance change during next decades/centuries.
Coastal tides and tidal Bore in the Severn Estuary from fast-sampled SWOT data
Authors: Arildsen Rasmus , Arildsen Rasmus , Andersen Ole
Published: March 2024

Satellite altimetry is instrumental in deciphering the dynamics of oceans and coastal regions. It yields indispensable data critical for monitoring global sea levels, predicting wave heights, and charting the courses of ocean currents and river elevations. These insights are pivotal for advancing climate research, ensuring navigational safety, and managing water resources effectively. Nonetheless, in coastal settings, the efficacy of conventional altimetry is constrained by its spatial resolution and the interference of land in the radar signal near the coastlines. These limitations hinder its ability to accurately capture the nuanced characteristics of dynamic and intricate coastal environments.The launch of the Surface Water and Ocean Topography (SWOT) satellite represents a monumental leap in the technology of satellite altimetry. With advanced high-resolution wide swath altimetry and innovative use of the phase difference between dual onboard antennas, SWOT drastically reduces the limitations of traditional radar altimeters. SWOT provides a 2D measurements grid with a detailed 50m grid spacing not degrading towards the coast. This marks a substantial enhancement compared to the 7-km across-track spacing along a 1D trajectory offered by conventional altimetry.This enhancement allows for the precise and detailed monitoring of dynamic coastal phenomena such as tides and tidal bores, even in estuaries.Tidal bores, characterized as sudden and powerful water surges against the river's current, are critical for local ecology, navigation, and flood management. Despite their importance, their dynamic and transient nature has made them challenging to study using conventional methods. The Bristol Channel, with its extreme tidal range and the presence of the Severn Bore, presents an ideal case study to demonstrate SWOT's capabilities.We use SWOT 50-meter pixel cloud data during the 1-day fast sampling repeat period in April 2023 to study the high-resolution tidal signal in the Bristol Channel - Severn Estuary and the Severn tidal bore. The results demonstrate that SWOT can capture both complex tidal signals associated with wetting and drying close to the coast, but also the tidal bore sweeping up the Severn River from the mouth of the river and some 20 km upstream.
Coastal boulders related to extreme marine events impacting the ABC islands (Aruba, Bonaire, Curacao islands, Leeward Antilles)
Authors: Scardino Giovanni , Barile Chiara , Nandasena Aruna Napayalage , Lahbi Tobia , Muletto Enrico , Chauveau Denovan , Boyden Patrick , Bejarano Sonia , Rovere Alessio , Casella Elisa , Kelly Harold , Mijts Eric , Scicchitano Giovanni
Published: March 2024

Extreme marine events determine different landform imprints, such as out-of-size deposits like coastal boulders with several tons in weight. These extreme marine events are usually connected to storms and tsunamis. Storms and tsunamis are characterized by a high-energy content, which is reflected in wave flow and wave height able to move the boulders. Several coastal boulders have been detected in Aruba, Bonaire, and Curacao (ABC) islands, overlying the marine terrace deposits that surround the seaward side of these islands. In this work, morpho-topographical surveys were performed on these coastal boulders in order to simulate the most probable events that caused their displacements. Unmanned Aerial Vehicle and close-range photogrammetry were used to reconstruct the volume and shape of boulders with their immersive scenario. Volume and shape of coastal boulders have been used to estimate the energy content able to determine their displacement. Furthermore, boulder samples were collected in order to assess their density and to obtain chronological constraints of the extreme marine events by applying U/Th and radiocarbon dating. Numerical models in Delft3D were applied to simulate the scenarios that could be responsible for the boulder movements. The results showed that the biggest boulders are located on Bonaire Island, located in the eastern part of the ABC archipelago, and were influenced by higher energy content than the Aruba and Curacao islands. This energy content could be related to three possible scenarios simulated in Delft3D: 1) a tsunami scenario connected to Venezuela earthquakes, 2) a Hurricane scenario impacting from the western side of the ABC archipelago, 3) a combination of multiple events (tsunami and storms) that caused differential boulders movement in the past.
Fossil to renewable – how to speed up the installation of borehole heat exchangers?
Authors: Glavanov Kosztadin Gergő , Markó Ábel , Domokos Pásztor , Mádl-Szőnyi Judit
Published: March 2024

Geothermal heat pumps coupled with borehole heat exchangers are appropriate tools to extract renewable and climate- friendly energy from the shallow subsurface. To properly construct these systems, knowing the initial temperature conditions is essential. However, drilling activity modifies the temperature field in the underground around the borehole as well as in the pipe placed into the borehole. During the installation it has to wait for a constant temperature in the pipe after the probe is placed, before measuring the final temperature. According to the rule of thumb, this period is usually one week. The objective of this study is to determine whether this time is really necessary or if a shorter period would be also enough for reaching the undisturbed temperature. The measurements took place in the 11. district of Budapest, Hungary. The analysed borehole was drilled with rotary method deepened into the Budai Marl Formation with a depth of 70 metres. We executed four measurements on the first day, two on the next day, and one after that for four days. The most significant differences can be noticed between the first day measurements. After the third day, the received curves fit better, but they only approached each other from the fourth day with only 0.1-0.2°C difference. It can be concluded that a stable temperature profile required 72 hours of resting for this specific case which is shorter than the supposed one week. With this knowledge, assuming similar behaviour in other cases, installation period of borehole heat exchangers can be significantly shortened. Next step of this research is investigating other geological and seasonal conditions to reveal potential deviations from the current results.The study was funded by the National Multidisciplinary Laboratory for Climate Change, RRF-2.3.1-21- 2022-00014 project.
Groundwater life expectancy simulations in strongly coupled density-dependent flow above a salt dome
Authors: Suilmann Jonas , Molson John , Graf Thomas
Published: March 2024

In the overburden of salt domes, salt is dissolved by groundwater, resulting in groundwater flow under highly variable water densities. Density-dependent flow is therefore important in assessing potential migration pathways for radionuclides accidentally released from high-level nuclear waste repositories located in salt domes. Groundwater life expectancy has been established as a safety indicator for radionuclide travel times and is therefore of particular interest.The objective of this study is to numerically investigate and understand the effects of uncertain transport parameters on density-dependent flow above a salt dome. The effects of density-dependent flow and salt transport, along with the transport parameters on the groundwater life expectancy are investigated numerically using the FEM code Saltflow. Groundwater life expectancy can be directly simulated using an advection-dispersion equation. The life expectancy depends on the transport parameters in two ways, first via the flow velocities calculated in the density-dependent flow simulation which depend on the dispersion terms, and second directly for the calculation of the life expectancy. This suggests a strong and also highly non-linear dependence of life expectancy on the transport parameters.Preliminary results support this interpretation. Longitudinal macrodispersivity shows a considerable influence on groundwater life expectancy. Strongly non-linear results are also obtained depending on the transverse vertical dispersivity. Increasing the transverse dispersivity up to a certain threshold leads to an increase of the maximum life expectancy in the model domain. Above this threshold, which depends on the longitudinal dispersivity, the maximum life expectancy decreases. Life expectancy also strongly increases with a decreasing diffusion coefficient. These results highlight the importance of considering uncertainty in the transport parameters when numerically evaluating groundwater life expectancy in density-dependent flow in the context of nuclear waste disposal.
Methane and carbon dioxide observations at Debrecen, Hungary: mole fraction and isotope ratio measurements in three different seasons
Authors: Varga Tamás , Major István , Bán Sándor , Baráth Balázs Áron , Röckmann Thomas , van Es Jacoline , van der Veen Carina , Molnár Mihály
Published: March 2024

The increasing level of atmospheric greenhouse gases and the effect of this trend, climate change, is one of the greatest environmental issues of the anthropogenic era. The increasing trend of greenhouse gas levels after industrialization is related to urban environments, where industrial and traffic-related activity and emissions are concentrated. In response to this, the European system, the ICOS (Integrated Carbon Observation System) was established and started the ICOS cities program, where coordinated greenhouse gas observations are carried out besides the regional background measurements and samplings. Similarly to this program, atmospheric air samples were collected at the Institute for Nuclear Research, Debrecen. During the sampling campaigns in three different seasons (winter, spring and summer), a minimum of 23 samples were collected in the morning and afternoon during weekdays and weekends as well. The samples are processed within a collaboration between Utrecht University, where the stable isotope composition of CO2 and CH4 were measured, and the Institute for Nuclear Research, Hungary, where the mole fraction of CO2 and CH4 and radiocarbon ratio of CO2 were measured. Based on the isotope composition results and stable isotope fingerprint of carbon dioxide and methane sources, the differentiation of the possible emission sources of these gases can be made. Using the radiocarbon, we can estimate the fossil CO2 contribution in urban areas. The preliminary results show that there is a great fossil contribution to the CO2 fraction, on the other hand, a great local biological contribution was observed in the CH4 fraction in every season. Based on measurements and literature, the source of the massive biological discharge could be the sewage pipeline system, even in winter. Our dataset shows that this kind of CH4 emitter can exceed fossil sources in Debrecen, Hungary.
Simulating infrasound waveguides in the middle atmosphere with ICON and UA-ICON: comparison with the IFS and ground-based remote sensing
Authors: Kristoffersen Samuel , Listowski Constantino , Wing Robin , Baumgarten Gerd , Khaykin Sergey , Hauchecorne Alain , Vergoz Julien , Le Pichon Alexis
Published: March 2024

Infrasound signals are used to monitor various anthropogenic (explosions, wind farms etc.) and natural (earthquakes, volcanoes etc.) sources. In particular, infrasound is included as one of the four verification technologies used by the International Monitoring System (IMS) by the Comprehensive Test-Ban Treaty Organisation (CTBTO). To determine accurate source locations and estimate source energy, an accurate model of wind and temperature from the surface up to the lower thermosphere is necessary. Operational NWP products are necessary for routine infrasound monitoring activities. However, the use of a sponge layer above ~30 km, to insure stable NWP models, leads to biases in the middle atmosphere (MA), where the relevant infrasound waveguides for long-range propagation are found. For UA-ICON, the sponge layer is set much higher in the thermosphere. Therefore, the UA-ICON, which provides modelled atmospheric parameters up to 150 km (110 km sponge layer height), is relevant in this context. First, to assess ICON and IFS operational analysis products, comparisons to lidar observations are made. The main differences between both products were analysed with respect to winds and temperatures in the MA, and hence with respect to the infrasound guide prediction. Second, UA-ICON simulations were performed and the outputs were compared to ICON and IFS fields to demonstrate the increased wave activity above ~30 km with UA-ICON. The added value of UA-ICON with respect to ICON and IFS products for infrasound propagation simulations is discussed. The comparisons between the remote sensing instrumental results and the models will be presented, as well as comparisons between modelled and measured infrasound propagation. 
A new protocol for fingerprinting cultural ochre sources using mineral magnetism
Authors: Crombie Maddison , Lise-Pronovost Agathe , Giansiracusa Marcus , Boskovic Colette , Roberts Amy , River Murray and Mallee Aboriginal Corporation n/a , Popelka-Filcoff Rachel
Published: March 2024

Provenance studies in ochre research are used to characterise the “fingerprint” of different ochre sources, providing the opportunity to trace the cultural movement of ochre in the archaeological past. Ochre pigment composition, and therefore the “fingerprint”, often varies between sites leading to source discrimination, but in many cases the composition can also vary within a site, and therefore presents an analytical challenge to develop methods that can differentiate this “fingerprint”. This work presents a novel protocol for the analysis of iron-based archaeological ochres from known sources within Australia and Kenya using geological mineral magnetism methods to disentangle complex mineral assemblages1. Magnetic properties have been largely unexplored as a tool for ochre provenance. However, the use of measurements such as room temperature – saturation isothermal remnant magnetisation (RT-SIRM), Hysteresis loops and zero field cooled, field cooled (ZFC-FC) allow for the identification of different magnetic minerals in the ochre samples, which can, in turn, be used to fingerprint ochre sources. This approach works towards understanding (1) the variation within and between sites and how this may differ based on source geologies and (2) the larger goal of tracing the movement of ochre from their sources to archaeological contexts and related ochre cultural exchange.(1) Lagroix, F.; Guyodo, Y. A new tool for separating the magnetic mineralogy of complex mineral assemblages from low temperature magnetic behavior. Frontiers in Earth Science 2017, 5, 61.
Water flow across the skin of the Earth – how badly are we doing?
Authors: Lehmann Peter , Duddek Patrick , Carminati Andrea
Published: March 2024

Despite its limited vertical extent, the thin soil layer provides essential functions for climate and ecosystems globally. For accurate large scale process description, land use models compute the water distribution in soils based on spatial domains with a width-to-thickness ratio of about 1000:1: a geometry as thin as a sheet of paper. Most models simulate the water flow in these ‘soil sheets’ by solving the Richardson-Richards equation in 1D, neglecting smaller scale structures and lateral flow, and implicitly making strong assumptions on the relations between water content, matric potential, hydraulic conductivity, and water flux. To quantify the accuracy of this conceptualization, we compare drainage simulations of wet soils for the 1D column simplification with the full 2D-and 3D geometry using the correct sheet-like size ratio. The role of different climates, soil types, and heterogeneities at smaller scale is analyzed. These simulations based on the full geometry provide guidelines for (i) the applicability of Richardson-Richards equation in land surface models and (ii) the development of appropriate averaging schemes of soil hydraulic properties in the 1D scenario.
The advantages of Standardization and Data Sharing: a swift compilation of a high-quality data set for seismological studies in the East Anatolian Fault Zone
Authors: Colavitti Leonardo , Tarchini Gabriele , Spallarossa Daniele , Scafidi Davide , Picozzi Matteo , Iaccarino Antonio Giovanni , Bindi Dino , Martínez-Garzón Patricia , Cotton Fabrice , Zaccarelli Riccardo
Published: March 2024

On 6 February 2023 at 01:17 UTC, the Mw 7.8 Pazarcık earthquake struck south-eastern Türkiye and Syria along the East Anatolian Fault Zone (EAFZ), in the province of Kahramanmaraş. The Mw 7.6 Elbistan earthquake occurred about 9 hours later, with an epicenter located about 95 km north-northeast of the Mw 7.8 quake. The combination of these two shocks produced a devastating effect with nearly 55,000 confirmed deaths and about 1.5 million people left homeless.In this work, we describe the Complete Automatic Seismic Processor (CASP) procedure that has been implemented to develop a large and comprehensive data set consisting of about 63,000 events of magnitude greater than 2.0, that occurred in south-eastern Türkiye between January 2019 and June 2023. The starting catalogue contains about 3.8 million waveforms recorded by 262 velocimetric and accelerometric instruments (network codes KO, TK and TU). The earthquakes were located using the Non-Linear Location technique (NLLOC) with a regional 1-D velocity model, based on the precise picking of P- and S-wave arrivals provided by the RSNI-Picker2 implemented in CASP. After several quality controls, the final high quality catalogue contains 8,475 well-located earthquakes, with a significant difference in depth with respect to the AFAD catalogue.We present the spatio-temporal distribution of earthquakes before and after the two mainshocks, as well as the distribution of strong-motion parameters, such as peak ground acceleration (PGA), peak ground velocity (PGV), and Fourier amplitude spectra (FAS). Furthermore, preliminary results on earthquake source parameters obtained by spectral decomposition applied separately to background and clustered seismicity are also discussed.The compiled data set can serve as a basis for studying seismic sequences during seismic crises and identifying the preparatory phase of strong earthquakes in geologically active areas.
Advanced Computational Analysis of Roof Stability in Highwall Phosphate Mining Operations
Authors: Sadki Mohamed Yassir , Karakus Murat , Amrouch Khalid , Eljabbar Bouazzaoui , Khaldoun Abdelhadi
Published: March 2024

Abstract:Strip mining is typically preferred for near-surface, tabular deposits such as phosphate. Khouribga, home to Morocco’s largest phosphate deposit, contributs significantly to the nation’s phosphate output. However, a slight dip in the phosphate deposit suggests that strip mining may become less viable in the future. To sustain phosphate production efficiently, transitioning from surface to underground mining through highwall mining could be an effective solution. This method, involving the recovery of phosphate using continuous miners, necessitates stable roof conditions.To evaluate roof stability in highwall mining, both with and without web pillars, we will employ a three-dimensional finite difference method. Firstly, field rock mass properties, including joint frequency, persistency, infills and orientations and mechanical parameters, will be determined for inclusion in the numerical model. The generalized Hoek-Brown failure model, in conjunction with the Geological Strength Index (GSI), will be utilized to analyze rock mass behavior. For intact rock behavior, triaxial tests will be conducted to acquire Hoek-Brown failure parameters. These parameters will inform the construction of realistic 3D models using FLAC3D software, enabling the simulation of various underground working scenarios to identify the optimal mine layout that ensures high production rates and minimizes roof stability issues.An economic analysis will also be conducted to assess the feasibility of this method. This analysis will help in optimizing the dimensions of highwall mining parameters and selecting the best scenario through the Mineable Shape Optimizer (MSO). This planning tool will additionally aid in forecasting the recovery and dilution rates associated with the highwall mining method.Keywords:Highwall mining, Phosphate, Khouribga, Roof stability, GSI, Rock mass classification, HoekBrown failure model, Economic analysis, MSO
Imagining the Deep Structure of a Mineralized Extensional Dome in the Variscan Central Iberian Zone (Spain) using Ambient Noise Seismic Data.
Authors: Palomeras Imma , Ayarza Puy , Gomez-Barreiro Juan , Martí David , Martínez-Catalán José Ramón , Sánchez-Sánchez Yolanda , Dos Santos Kelvin , Yenes Mariano , Pérez-Cáceres Irene , Barrios Santos , Élez Javier , DeFelipe Irene
Published: March 2024

During the late stages of the Variscan orogeny, generalized gravitational collapse with coeval magmatism took place in the Central Iberian Zone, in Iberia. This event is getting the attention of the scientific community due to its likely role in the generation of strategic mineral resources (i.e. Sn, W, Nb, Ta, Sc, Au, Sb). In this regard, to study how the Variscan orogenic architecture controls the generation of mineral deposits the GOLDFINGER project was born. As part of the project, the Martinamor gneissic dome (Salamanca), which presents several mineral deposits, was covered by 31 short-period (2 Hz) 3-component seismic stations. Through applying techniques of ambient noise seismic interferometry, we have constructed a 3D S-wave velocity model of the extensional dome, allowing us to extend in depth the geometry of igneous rocks, their host rocks, and some of the structures. Among the most relevant results, we have identified the depth configuration of a granitic body outcropping discontinuously east of the study area, and whose upper boundary has been interpreted as the extensional dome detachment level. This structure may have provided a pathway for mineralizing fluids. This work demonstrates that the seismic noise interferometry technique has sufficient resolution to interpret medium-scale structures and to discern different lithologies with moderately contrasted physical properties.Funding: grant PID2020-117332GB-C21 funded by MCIN/ AEI /10.13039/501100011033; EIT-Raw Materials project 17024 (SIT4ME: Seismic Imaging Techniques for Mineral Exploration); SA084P20 from the JCyL government, and TED2021-130440B-I00 funded by MCIN/AEI/10.13039/501100011033 and European Union NextGenerationEU/PRTR.
The past, current and future activities on statistical postprocessing in the context of the European Meteorological Network (EUMETNET) 
Authors: Vannitsem Stéphane , Demaeyer Jonathan
Published: March 2024

The new programs of EUMETNET have now been launched for 5 years (2024-2028). Within this context, new activities on statistical postprocessing have been proposed, supported by 16 National Meteorological Services. One key activity that will continue is the benchmark of different statistical techniques for correcting weather forecasts. Another one is the development of ready-to-use ensemble calibration techniques that will be available to the community, in particular using machine learning techniques. Finally, several workshops will be organized on the topic during the duration of the project. In this poster, we will discuss the past achievement on statistical postprocessing using the benchmark developed in the context of the previous phase of the project, the current activities, and the future plans in comparing the statistical methods.
Advancing Permafrost Monitoring: the EO-PERSIST Project 
Authors: Dermosinoglou Katerina , Detsikas Spyridon E. , Fratsea Loukia-Maria , Papadopoulos Apostolos G. , DiCaprio Giuseppe , Petropoulos George P.
Published: March 2024

Permafrost, a pivotal component of the Arctic ecosystem, remains particularly vulnerable to the effects of global warming, exerting profound impacts on both environmental and socioeconomic facets. In the light of increasing challenges posed by climate change, understanding and monitoring the dynamics of permafrost regions in the Arctic have gained paramount importance. In response to this critical need, the EO-PERSIST project [https://eo-persist.eu/], a 4 years MSCA staff exchanges project funded by EU, aims to leverage existing services, datasets, and innovative technologies to establish a consistently updated ecosystem with Earth Observation (EO)-based datasets suitable for permafrost applications.By harnessing advanced EO technologies, including innovative tools and datasets such as cloud platforms, and tapping into an extensive array of remote sensing datasets, EO-PERSIST aspires to revolutionize the monitoring and assessment of permafrost dynamics. The project aims to advance methodological approaches in the field of permafrost by leveraging the huge volume of remote sensing (RS) datasets and providing indicators directly linked to socioeconomic effects from permafrost dynamics.The aim of this study is twofold: (i) to provide an overview of the EO-PERSIST project and its objectives, and (ii) to present the results of a case study in which EO was utilized to map urban sprawl through monitoring Impervious Surface Areas (ISA), in an Arctic setting characterized by high structural density over the past decade. A pixel-based machine learning classifier in conjunction with Landsat imagery in Google Earth Engine (GEE) cloud platform has been employed to map with high accuracy ISA changes in Tromso area, Norway, from 1993 to 2023. The results of this study not only precisely map the urban changes in the study area but also hold promise of enhancing our comprehension of the dynamics behind urban expansion, the primary factors associated with urban sprawl and their interaction with the challenges posed by climate change in Arctic environments. All in all, results of this case study showcase the overall potential of EO datasets to be used for socioeconomic studies along with the recent advancements in cloud-based platforms paving the way for new opportunities and challenges.EO-PERSIST project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 10108638
Studying the Viability of Kinematic Rupture Models and Source Time Functions with Dynamic Constraints
Authors: Locchi Maria Eugenia , Mosconi Francesco , Supino Mariano , Casarotti Emanuele , Tinti Elisa
Published: March 2024

Earthquake is one of the greatest natural hazards and a better understanding of the physical processes causing earthquake ruptures is required for appropriate seismic hazard assessment. Kinematic modelling is a standard tool for providing paramount information about the complexity of the earthquake rupture process and for making inferences on earthquake mechanics. Despite recent advances, kinematic models are characterized by uncertainties and trade-offs among parameters (related to the non-uniqueness of the problem). It has been shown that, for the same earthquake, source models obtained with different methodologies can exhibit significant discrepancies in terms of slip distribution, fault planes geometry and rupture time evolution.One of the crucial assumptions in kinematic modelling on causative faults is the source time function, because it contains key information about the dynamics. Such function is nonetheless one of the most poorly observationally constrained characteristics of faulting. Recently, slip velocity time histories have been studied with laboratory earthquakes, and it has been observed that a systematic change of mechanical properties and traction evolution corresponds to a change in the shape of slip velocity. However, in kinematic inversions this function is a-priori assumed using simplified shapes, although functions compatible with rupture dynamics should be preferred.In this work, we run a series of forward and inverse modelling to investigate the effect of the assumed slip velocity function on the ground motion and on the inverted slip history on the fault plane. We generate spontaneous dynamic models and use their ground motion as real events, inverting these data with kinematic models. Kinematic inversions have been conducted using both single-time and multi-time windowing. Uncertainties have been investigated assuming four different source time functions (i.e., triangular, box, regularized-yoffe and exponential functions). In this way we examine how the slip velocity function influences the slip distribution on the fault plane, and test if the inferred kinematic parameters (rise time and rupture velocity) are consistent with the dynamic models. Also, for a dense grid of phantom receivers, we examine the variability of the peak ground velocity (PGV) of synthetic seismograms up to 1 Hz. The latter have been obtained with forward models assuming the same slip distribution, rise time and rupture velocity but changing the source time functions.Finally, we use the retrieved kinematic history on the pseudo-dynamic models to examine how different kinematic assumptions lead to a variability in the shear stress evolution. We focus on dynamic parameters such as breakdown work, stress drop, and Dc parameter. Our results provide a glimpse of the variability that kinematic source time functions (dynamically consistent or not) might have when used as a constraint to model the earthquake dynamics.
Quantifying thaw subsidence in a permafrost landscape (Bayelva basin, Svalbard)
Authors: Rolf Marie , Grünberg Inge , Hammar Jennika , Boike Julia
Published: March 2024

Rising temperatures have led to permafrost degradation throughout the Arctic. The melting of excess ground ice leads to a loss of structural support and consolidation of soils. As a consequence, the surface subsides, which, in turn, can accelerate further ground ice loss. Therefore, thaw subsidence is an important metric for monitoring permafrost degradation. With temperature rise reaching twice the Arctic and seven times the global average rate, warming trends in Svalbard are particularly high, leading to severe impacts on permafrost conditions. However, knowledge on subsurface permafrost changes in Svalbard is mostly limited to a few in situ observations. In this study, we aimed to spatially expand research on permafrost degradation by applying a multimethod approach to quantify thaw subsidence in the Bayelva basin (near Ny-Ålesund, Svalbard). First, during a field campaign in summer 2023, we measured Global Navigation Satellite System (GNSS) points and calculated elevation changes since an earlier GNSS survey in 2019. Second, we coregistered and differenced high-resolution digital elevation models (DEMs) for a period of more than 80 years (from 1936, 1995, 2008, 2010, 2019, and 2020) to identify spatial patterns of thaw subsidence over a larger area. Third, we analysed how thaw subsidence relates to various terrain attributes and land cover. By employing these methods, we clearly detected thaw subsidence in the Bayelva basin. The GNSS measurements showed a spatially averaged subsidence of 2.7 cm between 2019 and 2023. With DEM differencing, we observed annual surface subsidence in the order of metres for areas of glacial retreat, in the order of decimetres for moraines, and up to a few centimetres for tundra areas in the glacier foreland. We furthermore detected spatial variations in thaw subsidence throughout the tundra. We conclude that surface subsidence is an ongoing, widespread, and important process in Svalbard’s permafrost landscapes. In this study, we demonstrate the challenges of DEM coregistration in areas with a lack of stable terrain. Nevertheless, our results highlight the potential of GNSS measurements and DEM differencing for quantifying thaw subsidence in the Arctic.
From Frontier Research to Public Action: Some examples from projects funded by the ERC
Authors: Gallego Torres David , Oppenheimer Julie , Auvergne Noélie , Sielmann Jannik , Jansen Eystein
Published: March 2024

The European Research Council (ERC) aims to fund ground-breaking “bottom-up” research, with no predefined objectives or priorities. Moreover, evaluating panels are specifically instructed to evaluate proposals only based on scientific merits, and that societal impact is not an evaluation criterion. Nevertheless, projects that are originally unrelated to policy can produce results that are relevant for evidence-based policies and other public actions: public interest outcomes don’t necessarily come exclusively from research designed for societal purposes.In this presentation, we will showcase some examples of ERC-funded projects in Earth Sciences that resulted in societal/policy actions. Topics covered range from physical oceanography, to hydrology, fire monitoring, or atmospheric pollution. We will explain how the researchers expanded their activities beyond academia to engage in Science for Policy and other public services. Indeed, to bridge this gap between research and public action, ERC grantees followed a variety of paths: they created their own consultancies, they were invited after posting a “tweet”, or they focused on journalism and outreach, to name a few. Featured projects are only a few examples of how curiosity-driven research may have an impact beyond academic knowledge. The paths to influencing public policy are many, and the extra effort is worthwhile to ensure policy actions are based on the most advanced research knowledge.
Strategizing Building Resilience: A Big Data Driven Approach to Flood Risk Assessment and Management
Authors: Heo Han Kyul , Cho Youngjin , Hyeon Taehwan , Song Yumi , Kim Ho gul
Published: March 2024

The increased prevalence and intensity of flooding, exacerbated by climate change, pose significant risks to the structural integrity of buildings. A pertinent example of this was the 2022 flooding of Gangnam Station in South Korea, resulting in loss of life and amplifying concerns over flood-related damages. It is imperative to proactively assess the flood vulnerability of individual buildings to enhance public safety. This susceptibility is influenced by the building's unique characteristics and geographical location, necessitating their incorporation into flood mitigation strategies. This study endeavors to: (1) ascertain the flood risk of individual building units, and (2) suggest a management strategy to augment the flood resilience of buildings.Our analysis encompassed 27,438 instances of flood damage in Seoul from 2016 to 2022, correlating this data with detailed building registry information. We categorized buildings into two risk groups—low and high—based on a damage threshold of 3 million won. Employing a range of variables, our study developed a flood risk analysis model utilizing the TabNet classifier, achieving an impressive predictive accuracy of 88%. Key factors in assessing flood risk included the building's function, structural design, height, and floor area ratio, with smaller buildings identified as particularly vulnerable.The research revealed that flood hazard maps and flood risk maps display differing patterns. In certain areas, high flood probability coincides with low potential damage. This observation has two key implications: First, individuals in high flood probability but low damage areas might be exempt from stringent governmental oversight. Second, there are regions with low flood likelihood outside of government regulation that could still incur significant damage in the event of a flood.Leveraging the power of machine learning and deep learning, increasingly applied across various fields, this study integrates building attribute data with a plethora of spatial and socio-environmental factors. This integration has facilitated the creation of a comprehensive list of buildings particularly prone to flooding, utilizing public datasets and advanced deep learning techniques. Most identified high-risk buildings are small-scale structures, already under the purview of mandatory inspections by several legislations including the Building Management Act and others related to safety and fire protection. However, buildings classified as safety-vulnerable are not subject to regular inspections under current laws. Given the anticipated increase in flood events due to climate change, it is crucial to establish safety management standards tailored to specific building characteristics to effectively reduce flood-related damages.
Reviewing climate tipping point interactions and cascades under global warming
Authors: Wunderling Nico , von der Heydt Anna ,   GTPR-tipping-interactions-team
Published: March 2024

Climate tipping elements are large-scale subsystems of the Earth that may transgress critical thresholds (tipping points) under ongoing global warming, with substantial impacts on biosphere and human societies. While recent scientific efforts have improved our knowledge on individual tipping elements, the interactions between them are less well understood. Also, the potential of individual tipping events to induce cascading tipping elsewhere, or stabilize other tipping elements is largely unknown. As a contribution to the Global Tipping Points Report (GTPR) 2023 for COP28, we mapped out the current state of the literature on interactions between climate tipping elements. We find that tipping elements in the climate system are closely interacting, meaning a substantial change in one will have consequences for subsequently connected tipping systems. A majority of interactions between climate tipping systems are destabilising. While confirmation or rejection through future research is necessary, it seems possible that interactions between climate tipping systems destabilise the Earth system in addition to climate change effects on individual tipping systems. Further, we are quickly approaching global warming thresholds where tipping system interactions become relevant, because multiple individual thresholds are being crossed. Concretely, tipping cascades can neither be ruled out on centennial to millennial timescales at global warming levels between 1.5–2.0°C, nor on shorter timescales if global warming would surpass 2.0°C. To address crucial knowledge gaps in tipping system interactions, we propose four strategies forward combining observation-based approaches, Earth system modelling expertise, computational advances, and expert knowledge.
Thermal evolution of the Galilean moons’ embryons during their accretion phase
Authors: Bennacer Yannis , Mousis Olivier , Monnereau Marc
Published: March 2024

The extent of differentiation of the Galilean moons interiors is still not well assessed. The moments of inertia of Callisto retrieved from Galileo’s gravity data suggest that its structure is not fully differentiated. Also, a recent reanalysis of the Galileo data questions the very existence of Europa’s metallic core postulated since decades. Here we aim at understanding the accretion conditions of the Galilean moons that would enable them to grow free of global melting and differentiation. To do so, we use a numerical model that mimics the thermal evolution of the interiors of icy moons during their accretion and post accretion phases. Each moon’s embryo experiences tidal heating, radiogenic heating, accretional heating due to multiple impacts and heating from the ambient environment circumplanetary disk during its growth. The extent of each considered heating process depends on the assumed formation path of each moon within the Jovian circumplanetary disk. We thus explore the best-case scenarios explaining a Callisto-like moon that is partially differentiated, and a Ganymede-like moon that is fully differentiated. The case of a Europa is also investigated, and specifically the conditions enabling the melting of iron and the formation of a metallic core.