bluuebunny/crossref_metadata_2025 huggingface dataset:
Anatomy of a detachment fault damage zone at a nearly amagmatic mid-ocean ridge: observations from outcrop to map scale
Authors: Mahato Souradeep , Cannat Mathilde
Published: February 2023

The eastern Southwest Indian Ridge (SWIR) is a melt-poor end-member region of the global MOR system. The available magma focuses to axial volcanoes, leaving >50 km-wide, nearly amagmatic ridge sections, where seafloor spreading occurs via large offset detachment faults. We present map to outcrop scale observations of the deformation associated to one of these detachments, in the 64°35'E region of the SWIR. This active detachment fault presently has a horizontal offset of ~4 km (Cannat et al., 2019), and accommodates nearly all the plate divergence (14 km/million year; Patriat and Segoufin, 1988). We focus on the lower slopes of the footwall, where this active fault currently emerges at an angle of ~35°. The emergence is traceable across a length of ~20 km on side-scan sonar and shipboard bathymetry data. It locally shows undulations at a wavelength of ~1-4 km. High-resolution bathymetry at and near the emergence area shows two morphological domains. In one domain, the exhumed fault surface bears distinct corrugations that trend at an 18° to 33° angle to the spreading direction, extends up to 300 m, are spaced by ~15-300 m, and are ~1 m to ~40 m in amplitude. In the other domain, the exhumed fault is not corrugated. Remotely operated vehicle (ROV) dive observations at the outcrop scale show discrete planar fault planes and brecciated and fractured rock forming the top ~1-4 meters of the corrugated exposures. In contrast, the non-corrugated fault exposures show up to ~8 m of gouge-bearing micro-brecciated domains, including several up to 1 m thick horizons of semi-brittle sheared serpentinites. Dive observations further suggest that: (1) there are several sigmoidal intercalations of such gouge-bearing horizons forming the upper few tens of meters of the non-corrugated fault zone, and (2) the horizons of sheared serpentine originated as brittle cracks that served as hydrous fluid pathways into the fault damage zone. We propose: (1) that the absence of corrugations is related to the overall weaker semi-brittle rheology of the emerging fault in this domain, compared to the purely brittle corrugated domain; and (2) that the two domains represent damage developed in distinct conditions of temperature and hydrothermal fluid availability. At the broader map scale, the non-corrugated domain to the east emerges about 1.2 km farther south than the corrugated domain, and the trace of emergence thus draws an indentation between the two domains. Given the ~35° fault emergence angle in the two domains, we infer that their across-fault distance is ~650 m. The detachment damage zone may thus be at least that broad, and comprised of distinct, probably anastomosing domains of more localized deformation, which would preferentially be exposed at the seafloor. This damage zone anatomy would be consistent with seismic refraction observations (Momoh et al., 2017) in the area.
Critical Raw Materials supply in the EU: the case of Sb-rich Pb-Zn-Au mineralization, Chalkidiki, Greece
Authors: Bussolesi Micol , Cavallo Alessandro , Grieco Giovanni , Tzamos Evangelos
Published: February 2023

Antimony is a strategic element, widely used in the production of alloys, halogen-bearing flame retardants and semiconductors. As the main antimony supplier is China, new providers in the EU are necessary in order to decrease its criticality.The present study aims to evaluate the antimony enrichment of the Pb-Zn-Au carbonate replacement Stratoni deposit, Chalkidiki, Greece. The mineral assemblage comprises galena, sphalerite, pyrite and arsenopyrite ± subordinate phases such as boulangerite, bournonite, chalcopyrite, pyrrhotite and graphite.Boulangerite (Pb5Sb4S11) is the most abundant Sb phase, and occurs as long acicular crystals within galena, the matrix or massive pyrite. Crystal size ranges between 10 and >100 µm. Bournonite (PbCuSbS3) is less abundant, and occurs associated with boulangerite, included in pyrite as small crystals (<20 µm).Boulangerite shows Sb contents ranging between 25.64 and 26.45 wt%, whereas bournonite shows Sb contents between 23.37 and 25.23 wt%. Base metal sulfides contain low amounts of Sb: up to 0.44 wt% within pyrite, up to 0.21 wt% within sphalerite and up to 0.28 wt% within galena. Arsenopyrite and chalcopyrite Sb contents are even lower.The enrichment plant works in three consecutive stages, producing galena, sphalerite and pyrite concentrates. Each stage comprises conditioning, roughing, scavenging and cleaning flotation cells.Grain size analyses show similar granulometric curves for the concentrates, with uniformity coefficients lower than 3. D90, D50 and D10 are respectively 400, 110 and 45 µm for galena, 127, 60 and 42 µm for sphalerite and 240, 105 and 49 µm for pyrite concentrates.Whole rock major (XRF) and trace element (ICP-MS) analyses show that most of the antimony, and therefore of boulangerite and bournonite, reports to the galena concentrate. Starting from 1169 ppb in the initial feed Sb is highly enriched in the galena concentrate (20633 ppm), not enriched in the sphalerite concentrate (1170 ppm) and relatively depleted in the pyrite concentrate (334 ppm), making the galena concentrate a suitable candidate for Sb recovery.The presence of Sb mostly in its own phases opens up the potentiality to recover the metal as a by-product of galena production. The crystal size of boulangerite is large enough to allow separation through flotation. Further tests are necessary in order to evaluate the amount of Sb phases in tiny inclusions within base metal sulfides and Sb enrichment in base metal phases, that can negatively affect the metal recovery.
Stationarity assessment of hydroclimatic variables for a tropical river basin
Authors: Singh Achala , Sharma Priyank , Teegavarapu Ramesh
Published: February 2023

Understanding the space-time variations and dependency between hydroclimatic variables is vital for predicting future changes towards adaptive water resources management in a changing climate. Globally, it is observed that the mean and extreme hydroclimatic conditions are experiencing a significant shift under a changing climate, which affects the spatio-temporal distribution of floods and droughts. However, climate change studies seldom talk about the time invariance of the characteristics of a hydroclimatic time series. This research assesses the time invariance of the statistical properties of hydroclimatic variables (such as rainfall, temperature, streamflow and their derived indices) for a tropical river basin (i.e., the Tapi River basin) in India. Climate change profoundly impacts tropical river systems. Hence, assessing and detecting stationarity in hydrologic processes for such a river basin is imperative to predicting future changes. In this study, we have analyzed nine hydroclimatic variables representing the mean and extreme rainfall, temperature and streamflow. The hydroclimatic indices have been statistically examined to detect stationarity, homogeneity, and trends. A non-overlapping block stratified random sampling approach has been applied to identify the time invariance of hydroclimatic indices. The stationarity assessment approach investigates the similarities in the median, variance, distribution, and statistical moments of the continuous time series data. Based on the results of this study, weak and strict stationarity can be identified. The findings have significant ramifications for the planning and design of hydraulic structures, stormwater networks, flood mitigation, and disaster management for the Tapi basin.
Thermal spallation and fracturing of rocks produced by surface heating
Authors: Guo Yide , Pasternak Elena , Dyskin Arcady
Published: February 2023

Heating of rock surface (e.g., flame heating) induces compressive stresses in the surface layer and tensile stresses of lower magnitude in the layer beneath. If the heating temperature is large enough (around 900 deg for shales), the compressive stresses initiate spallation produced by pre-existing cracks that and extensively grow parallel to the surface under compression. The extensive cracks separate thin layers from different parts of the heated surface which eventually buckle opening a new surface which starts being subjected to flame heating. Then the spallation process repeats itself producing a cavity of approximately cylindrical shape growing into the rock normal to the surface. The presentation reports the results of tests on flame heating of shales, which demonstrate that the spallation process is accompanied by emergence of a large tensile fracture normal to the surface. In order to check whether the fracture can be produced by tensile thermal stresses induced in the layer situated under the compressed layer we conducted a series of finite element simulations of thermal stresses for different spallation depths (depths of the cavity). The modelling shows that: (1) as the spallation cavity deepens the magnitudes of maximum compressive and tensile stresses remain approximately the same except of two peaks at the spallation depths of about 6% and 30% of the diameter of the heating flame; (2) the magnitude of the maximum tensile stresses is about half of the compressive stress. Given that the spallation strength is about half of the UCS (e.g., [1]) and that the tensile strength is often up to an order of magnitude lower than the UCS, the induced tensile thermal stresses can be considered as sufficient to produce the tensile fracture. The experiment and computer modelling suggest that the production of tensile fractures is an intrinsic feature of the spallation process. These results can assist in understanding large scale spallation-like processes in the Earth’s crust and design rock cutting based on thermal spallation. Wang, H., A.V. Dyskin, Pasternak, P. Dight and B. Jeffcoat-Sacco, 2021. Fracture mechanics of in-situ spallation. Engineering Fracture Mechanics, 260, 108186.
Are temperate tree species able to adjust root-water uptake depth during drought?
Authors: Steger David N. , Peters Richard L. , Hoch Günter , Arend Matthias , Zahnd Cedric , Kahmen Ansgar
Published: February 2023

Temperate trees are facing an increasing challenge from limited water supply and increased atmospheric demand due to an extreme trend in drought events. Particularly, structural-morphological traits such as root-water uptake depth (RWUD) are key for determining the performance of a species during drought. In addition to RWUD, ultimately understanding the temporal origin of the soil water used by trees could provide important insights into a species drought vulnerability.

The goal of this study is to determine the ability of species to adjust RWUD during drought. For this purpose, we analyzed ∂2H and ∂18O isotope data from xylem water samples collected from mature trees of nine co-occurring temperate tree species growing at the Swiss Canopy Crane II site in Switzerland, over three growing seasons (2020 ­– 2022). Additionally, we analyzed bi-weekly water samples from precipitation, throughfall, and soil water at different depths. Both 2020 and 2022 were relatively dry (compared to the reference of 1991-2021), while 2021 had a wet summer, allowing us to identify RWUD dynamics within a wide range of soil water supply. We applied the LWFBrook90.jl hydrological model to assess RWUD dynamics as response to variability in soil moisture and soil water potential in high temporal resolution.

Initial results revealed distinct species-specific differences in the summer ∂2H and ∂18O isotopic signals. Xylem-water ∂2H and ∂18O values of Quercus sp., Fraxinus excelsior and Sorbus torminalis were the lowest and coincided with soil water values in deeper soil. These patterns were contrasted by Carpinus betulus, Picea abies and Abies alba showing highest ∂2H and ∂18O values and a suggested predominant RWU in the top soil. Fagus sylvatica and Pinus sylvestris showed variability within their values suggesting RWUD adjustment.

The initial findings already indicate different rooting strategies as well as a certain level of resource partitioning within the rhizosphere. We expect the final results of this study to have significant implications for understanding the mechanisms behind drought vulnerability of temperate trees and for improving the prediction of tree species' responses to an altered hydrological regime.
Cloud-based quantification of Spatial Explicit Uncertainty of Remote Sensing-based Benthic Habitat Classification and its utilization in the context of Active Learning
Authors: Christofilakos Spyridon , Pertiwi Avi Putri , Lee Chengfa Benjamin , Traganos Dimosthenis
Published: February 2023

With the latest advances in cloud image processing, scientists and policy makers have found an effective and robust platform to process vast satellite data in order to be able to map the extent, monitor the condition and create effective protection policies for different ecosystems across the globe. Cloud-based techniques though lack information on the spatial explicit uncertainty of the mapping algorithms. In this study, we present a novel approach on the estimation of uncertainty in a benthic habitat classification context. We explore the benefits of such information in the context of better classification results through an ensemble classifier and the visualization of the uncertain areas in an attempt to provide better maps to the policy makers. The study area consists of Komodo and Wakatobi islands in Indonesia while reference and satellite data come from the Allen Coral Atlas(ACA) project sampling and a six-year PlanetScope composite, free of clouds and optical deep waters Our semi-automated algorithm is divided in three sectors. The first one prepares the data in the context of sampling a number of subsets of reference points according to ACA map products and runs the first classification based on the first subset. The second one aims to help the model re-train itself in a data driven way by accepting training points of the remaining subsets that have mediocre to low uncertainty scores. The uncertainty score is calculated based on probabilistic principles and the theory of Information. The last stage consists of three ensemble classifiers with the inputs of the classification of the second sector. The ensemble classifiers produce three different map products based on mode, max likelihood and simple weighted average values, respectively. According to the results, our workflow is able to minimize the noise of reference points, especially when they come from mapping products and non in-situ measurements. Furthermore, accuracy scores following retraining are better than the initial ones which verifies the hypothesis of removing training data with noise in an attempt to reduce the introduced bias in the classification model. Last but not least, the bi-product of classification uncertainty map can be utilized as a tool for better in-situ sampling planning and render a better understanding to policy makers regarding the validity of scientific reports such as change detection, satellite derived bathymetry and blue carbon accounting, among others.
Assessing Multi-Hazard Livelihood Security and Resilience of Lower Mekong Basin Communities
Authors: Baskota Ayush , Pal Indrajit , Dhungana Ganesh , Udmale Parmeshwar , Gadhawe Mayuri , Doydee Puvadol , Nguyen Tanh , Seak Sophat
Published: February 2023

The Lower Mekong Basin (LMB) is a subsidiary region of the Mekong River, with approximately 10 million people directly dependent on the river for livelihood and economic activities. However, communities in the region are increasingly exposed to multiple hazards that have significant direct and indirect impacts on their livelihoods. The Asia-Pacific Network for Global Change Research, Japan supported project aims to develop a multi-stakeholder Livelihood Security and Resilience Assessment (LiSeRA) framework by studying the dimensions and factors influencing livelihood security and resilience in communities living in the LMB region.This paper studies the multi-hazard scenario and impacts in the LMB region, the interlinkages between livelihood and resilience, and proposes a localized assessment framework that can be used by stakeholders in decision-making process. Floods, droughts and tropical storms were identified as primary natural hazards, while a multi-hazard assessment highlighted a wide spatial variation in the hazard levels across the region. The proposed framework provides a tool to measure the multi-hazard livelihood security and resilience in LMB communities, and can be used by government authorities and development partners in planning and implementing mitigation and preparedness activities to manage and reduce the risk of hazards.
Plant water use strategy is strongly constrained by species size in Mediterranean ecosystems
Authors: Muñoz Gálvez Francisco Javier , Querejeta Mercader Jose Ignacio , Moreno Gutiérrez Cristina , Ren Wei , González Barberá Gonzalo , García de la Riva Enrique , Prieto Aguilar Iván
Published: February 2023

Global warming and changes in precipitation regimes resulting from climate change are altering plant water availability and water use efficiency, which compromises key ecosystem services such as vegetation productivity, ecosystem carbon storage, and ecohydrological regulation. The study of plant water sources and leaf-level water use strategies is particularly important for the management and conservation of Mediterranean ecosystems, which are threatened by increasing climatic aridity. We investigated the water use strategies of 66 woody plant species distributed across 10 sites along a steep 600 km aridity gradient in  south-eastern and central Iberian Peninsula. We used soil and plant water stable isotopes (δ2H and δ18O) to quantify the proportion of water extracted from different soil layers, as well as leaf stable isotopes (δ13C, δ18O and Δ18Oenrichment above source water) as proxies for water use efficiency and stomatal regulation. Our results indicate that water extraction depth along the soil profile is strongly constrained by plant species size and height. Bayesian models revealed that small and medium size shrubs use a much greater proportion of shallow soil water than large shrubs and trees, a pattern that is remarkably consistently across study sites and species. Mixed models revealed strong associations between leaf δ13C, Δ18Oenrichment and xylem water δ18O across sites, indicating that woody species with tighter stomatal regulation achieve higher water use efficiency and generally extract water from deeper soil layers. This conservative water use strategy is much more common in larger woody species than in smaller ones. Our findings demonstrate the coexistence of sharply contrasting water use strategies in Mediterranean plant communities.  Small and mid-size woody species are heavily reliant on shallow soil water and exhibit a highly acquisitive and profligate water use strategy that enables them to take rapid advantage of an ephemeral resource (topsoil water) after rainfall pulses, although they are less efficient in the use of water at leaf level. On the other hand, large shrubs and trees that use more stable deeper water sources exhibit a much more conservative water use strategy. 
Topographic signature of badlands landscapes
Authors: Avcioglu Aydogan , Schwanghart Wolfgang , Görüm Tolga , Yetemen Ömer , Moreno-de las Heras Mariano , Yang Ci Jian
Published: February 2023

 As part of the earth's dynamic systems, badland landscapes are chiefly generated by the interaction between bedrock weathering, climate seasonality, and the controversial contribution of the hillslope and fluvial erosion processes. Although contemporary definitions clearly point out that badland initiation is a function of overland-flow-dominated gully channels, gravitational processes-dominated mass movements, and subsurface processes-driven piping, the following related questions remain to be tackled regarding their topographic position in the landscape: (1) Are the badland landforms signature of hillslope or fluvial erosion domain? (2) How do climate and regional settings (i.e., macro landforms, homogenous or heterogenous lithologies, etc.) influence the topographic position of badlands? To address these questions, we have selected climatically distinct badlands from different continents where; digital elevation models are available: Utah and South Dakota (USA), Upper Llobregat and Murcia (Spain), Northern Apennines and Basilicata (Italy), Mediterranean and Plateau – Margin Transition Badlands (Turkey), and Southern Taiwan. The badland boundaries were visually inspected and manually digitized based on diagnostic morphologic indicators. We have utilized the slope and drainage area relationship by using a 5m digital terrain model to identify topographic thresholds at TopoToolbox, a MATLAB-based software for topographic analysis. Preliminary results show that most badland areas occupy a maximum of 104 to 105 m2 contribution area in the landscapes. Although contribution areas relatively represent uniform thresholds in the sites, the local gradient (S), which is proportional to the contribution area, tends to be higher in the sub-humid mountainous badlands (Upper Llobregat, Northern Apennines) and wet tropical SW Taiwan than in semi-arid badlands (Basilicata, Murcia). We conclude that the topographic signature of badlands in the context of the sub-catchment scale may depict an appropriate instance of a transitional domain from a diffusive erosional process to a fluvial erosion process. Our findings may serve as a foundation for a better understanding of the classification and automatic detection of badland landscapes, also known as erosional hot spots.This study has been produced benefiting from the 2232 International Fellowship for Outstanding Researchers Program of the Scientific and Technological Research Council of Turkey (TUBITAK) through grant 118C329 and TUBITAK 2214-A International Research Fellowship Programme.  
Near Real-Time Depth Change Monitoring on Inland Water Bodies Using Sentinel-1 and Dynamic World Data
Authors: Ünalan Utku Berkalp , Yüzügüllü Onur , Aksoy Ayşegül
Published: February 2023

Monitoring the depth changes in lakes is crucial to understanding hydrological dynamics and water quality changes. In developed countries, the authorities monitor the lake depths regularly; however, it might be different in developing and underdeveloped countries. In this study, we aim to develop a near-real-time SAR-based depth change monitoring system for lakes by focusing on shoreline pixels. For this purpose, we developed a framework using the Sentinel-1 GRD and Sentinel-2 Dynamic World land cover datasets available on the Google Earth Engine. Sentinel-1 data provides us with the necessary temporal resolution for frequent monitoring. For the initial development phase, we consider five ground monitoring stations in Sweden and one in Turkey. The approach starts by detecting water bodies within a selected area of interest using Sentinel-1. Then it extracts shoreline pixels to calculate the change in the VV and VH sigma naught and VV-VH and VV+VH Pauli vectors. Extracted differences are further classified according to the temporally closest Dynamic World data to handle the temporal difference for each land cover type. Next, we eliminate outlier values based on the percentiles, and from the remaining data, we sample each landcover class for modeling. From many of the tested frameworks, we obtained an R2 of 0.79 with Gaussian Process Regression. Currently, in this framework, we observed an underestimation of higher values and an overestimation of lower values within a range of ±0.4 cm. Furthermore, considering the chosen six lakes, we observed a negative correlation between depth change and polarimetric features obtained from samples taken from land covers of grass and flooded vegetation, which is typical for natural lakes. In the second step of the development, we will increase the number of samples by including lakes from Switzerland and further develop the model.
Hydropeaking: a multiscale perspective
Authors: Chiogna Gabriele , Basilio Hazas Monica , Marcolini Giorgia , Pérez Ciria Teresa , Ziliotto Francesca
Published: February 2023

This presentation aims at covering different and interdisciplinary research aspects focusing on hydropeaking, highlighting in particular which temporal scales are relevant at different spatial scales. We will present how the impact of hydropeaking at the catchment scale changed in the past decades due to changes in legislation and the energy market and the role of hydropeaking in the context of energy complementarity. We will then focus on the effects of sudden river stage fluctuations at the reach scale and their impact on surface water-groundwater interaction and eventually on energy and mass transfer processes, considering seasonal, weekly and sub-daily time scales. Finally, laboratory scale investigations will show the effects of hydropeaking on solute mixing in porous aquifers. The environmental impact of hydropeaking on the ecosystem calls for effective mitigation strategies and policies to find a sustainable compromise between energy production and ecosystem preservation which are capable of tackling processes occurring at multiple spatial and temporal scales.
Comparison of extreme value distributions for significant wave heights in the Mediterranean Sea
Authors: Görmüş Tahsin , Aydoğan Burak , Ayat Berna
Published: February 2023

The investigation of extreme sea conditions is of great importance regarding to the design and survivability of marine and offshore structures. Accurate quantification of the storm events in terms of the n-year return levels is needed. Extreme value distributions are used to analyze the extreme waves in the interested location, but the comparison of the distributions is usually ignored. This comparison is important, since a small deviation could mean much higher differences in the design parameters of the structures. This study evaluates the extreme wave conditions in the prescribed locations located in the Mediterranean Sea by quantitatively comparing different statistical distributions. The recent ERA5 dataset is used for the analysis. Statistical distributions of Generalized Extreme Value (GEV), Gumbel, Weibull and Lognormal are used based on the Annual Maximum Series (AMS); Weibull and Generalized Pareto Distribution (GPD) are used based on the Partial Duration Series (PDS). Peak-over-threshold method is used with 99.5th percentile threshold of the hourly 42-year long time-series after careful considerations of the alternatives found in the literature regarding to the threshold selection. The return levels of the significant wave height (Hm0,N) for each of the selected location is computed using the relation Hm0,N=F-1(1-1/λN) in where F denotes the cumulative distribution function of the used statistical distribution, N is the return period in years, and λ is the yearly frequency of the extreme events in the extracted time-series. The distribution parameters are acquired using the maximum likelihood approximation. The comparison of the distributions is made using the Anderson-Darling (AD) test. Mediterranean Sea exhibits diverse sea conditions. 12 spatially distributed locations are selected to represent the wave climate in the basin. The analysis clearly depicts the importance of the statistical distribution model selection. In the Gulf of Lion, 100-year return level Hm0,100 ranges between 9.5 m (Weibull/AMS) and 11.3 m (Gumbel/AMS). Inter-model uncertainty increases with the increasing return period. It is evaluated that the characteristics of the extreme wave series are determinative over the fitting accuracy of the distributions. Considering the best-fitting distributions among the 12 selected locations throughout the basin, the Hm0,100 values range between 4.9 m and 9.8 m. GEV distribution is selected as the best-fitting AMS distribution in five of those locations by the AD test, where for PDS models, Weibull distribution is outperformed the GPD in 11 points. This research is a part of a project supported by The Scientific and Technological Research Council of Turkey (TÜBİTAK) under grant number 122M279, and the first author is also supported by TÜBİTAK 2211 PhD scholarship programme.
Cloud and precipitation profiles from observations and Polar-WRF simulations over Vernadsky station (western Antarctic Peninsula) during austral winter 2022
Authors: Chyhareva Anastasiia , Krakovska Svitlana , Gorodetskaya Irina , Palamarchuk Lyudmyla
Published: February 2023

Intense moist intrusions originating from the lower latitudes of the Pacific Ocean have been found to have a significant impact on the Antarctic Peninsula (AP), including enhancement of surface melt events, increased runoff, reduction in sea-ice cover and ice shelves destabilization. Clouds play an important role in the surface energy budget during these events and in precipitation formation. Precipitation phase and amounts determine local and regional surface mass and energy budget. Our  research focuses on cloud and precipitation microphysical and dynamic characteristics over the AP region, using  ground based remote sensing at the Ukrainian Antarctic Station Akademic Vernadsky Moreover, an enhanced radiosonde program was launched during the austral winter at the Vernadsky station as part of the Year of Polar Prediction in the Southern Hemisphere (YOPP-SH) international initiative (May-August 2022). Here we present detailed analysis of one of the Targeted Observing Periods (TOPs) during an intense moisture and heat intrusion affecting the AP.Although there is a lot of research on the atmospheric processes over the AP region, the local dynamic and microphysical characteristics of clouds and precipitation are still poorly understood and misrepresented in the models due to the lack of direct measurements, particularly in winter.Further we performed  Polar-WRF model simulations, forced by ERA5 reanalysis and configured with Morrison double moment cloud microphysical scheme. The simulations were run at 1-km spatial resolution with 10-minute temporal output centered over the Vernadsky region. Simulation results were verified with precipitation properties derived from Micro Rain Radar-Pro measurements and radiosonde profiles. We found that there is  more snow in PolarWRF outputs in comparison to MRR-Pro measurements. Thus it does not represent mixed phased precipitation properly. At the same time Polar WRF shows warm temperature bias compared to radiosounding. Measurements and model output are used to analyze cloud ice and water particle distribution, thickness and precipitation particle spectra over the Vernadsky station and the AP mountains during the extreme precipitation events in the Antarctic Winter. In overall there were five TOPs over the AP region. However, not all of them were associated with extreme precipitation on Vernadsky station.Our preliminary results show the importance of the transition between dry and wet snowfall during intense moisture transport events at the AP (particularly remarkable during winter at the location of Vernadsky station). Polar-WRF shows differences in simulating the timing and intensity of such transitions probably related to the biases in temperature profiles influencing the melting layer height.
Effects of Super-Extremes in the evaluation of the design rainfall: a case study in Northern Italy
Authors: Mazzoglio Paola , Butera Ilaria , Claps Pierluigi
Published: February 2023

In recent years, several major rainfall events have been observed in Italy, with amounts that have broken previous all-time records. Several questions concerning the adequacy of the statistical tools that we have at our disposal to determine the "real" rarity of these events emerge, especially considering the limited availability of long and complete rainfall records. In this work, we investigate the influence of "Super-Extremes" on the rainfall regional frequency analysis framework. More specifically, we consider the all-time Italian record events up to now, some of which were observed in 2021 (377.8 mm / 3h, 496 mm / 6h, 740.6 mm / 12h).The approach is undertaken through a rainfall regional frequency analysis performed over the North-West of Italy based on the patched kriging (PK) technique. PK requires a year-by-year application of ordinary kriging, that overcomes the data inconsistency by considering all the time series, without the need to discard those shorter than a specific length. The morphology of the areas is quite complex, which implies that extremes are expected to be influenced by the elevation: the orographic gradient is computed and removed and, for each duration, the sample variogram is evaluated as the mean of the annual variograms weighted on the number of active rain gauges for any year.The sequential application of the ordinary kriging allows to reconstruct both a "rainfall data cube" and a "variance data cube" in the (x, y, t) space. A complete series of measured and estimated values are obtained by coring the data cube along the time axis in each location. The cored series are then used to compute the L-moments, in a framework that assigns weights based on the kriging variance, to consider the different nature of the data (measured and estimated). To overcome possible inconsistencies of the L-moment, a bias-correction procedure is applied to preserve the coefficient of variation from the smoothing effect induced by the spatial interpolation.The methodology is applied to short-duration (1 to 24 hours) annual maximum rainfall depths recorded by rain gauges coming from the Improved Italian – Rainfall Extreme Dataset (I2-RED). The effects in the local frequency curves when introducing new record-breaking data are examined and commented, in view of the role that these values assume in the surrounding region.
Can we monitor shallow groundwater using ambient seismic noise?
Authors: Kiel Antonia , Steinmann René , Larose Eric , Hadziioannou Céline
Published: February 2023

Nowadays, the majority of detailed information about groundwater is acquired by wells that provide limited insight in time and especially space. Therefore, it would be interesting to monitor groundwater by continuously measuring seismic velocity changes in the subsurface. The shallow soil is affected by environmental influences like temperature, rainfall or drought, which in turn changes the seismic velocity in the subsurface.In this study, we use three-component seismometers, which are placed next to an in-situ measurement station of soil conditions (moisture and temperature at different depths) and a meteorological station in the city of Hamburg, Germany. We investigate the sensitivity of high-frequency (> 1 Hz) seismic waves with an anthropogenic origin to ground moisture changes in the uppermost layers of soil. To monitor velocity changes, Passive Image Interferometry is applied. Using the three-component data, we are able to retrieve Rayleigh and Love waves. Relative velocity changes are retrieved using the stretching method. A comparison of seasonal seismic velocity changes and environmental changes shows a positive correlation between velocity and temperature, as well as a negative correlation between velocity and groundwater content. Freezing events are exceptions, as they cause relative velocity increases twice as high as seasonal changes.The aim of this work is to eliminate temperature effects to work towards inferring water content directly from seismic velocity changes. To eliminate the contribution of temperature, its relation to seismic velocity changes and water content is quantified using regression. Since the relative velocity change is influenced by both temperature and water content, a time period of stable water content is used to quantify the relation between velocity change and temperature. As a result, the residual relative velocity change reproduces the residual water content.
Hydrologic modelling of seasonal runoff generation during heavy rainfall: Effect of decentralized water retention measures at a flood-prone site in Trier (Germany) – A study concept
Authors: Jackel Mathias , Schuetz Tobias
Published: February 2023

Due to the climate change-related increase in extreme weather events and scenarios such as the flood disaster in Western and Central Europe in July 2021, an increased research effort is necessary in order to better predict the dynamics of such events and consequently create preventive measures. Due to a lack of water retention capacity and insufficient drainage structures, the vulnerability is high in and around of settlements where infrastructures are not sufficiently adapted for extreme precipitation. Since not only the sealed surfaces in urban areas contribute to the development of runoff processes, but the entire catchment area, the process dynamics of the outer areas of settlements must also be increasingly researched.This study is part of the collaborative project “Urban Flood Resilience - Smart Tools (FloReST)”, which is funded by the German Federal Ministry of Education and Research and is dedicated to the exploration of measures to determine and increase the resilience of existing infrastructures.Our scope is to analyze the effect of different flood prevention measures on an existing drainage infrastructure in the municipality of Filsch (Trier), which in the past could not fulfill the purpose of drainage and thus flood damage occurred frequently.The connected runoff generating area is mainly used for agriculture. Despite an adapted cultivation method with the no tillage method and a 5-stage crop rotation that ensures a soil cover over the whole year several flooding events occurred due to surface runoff generation. Local farmers have reported that this slope does not always generate surface runoff throughout the year for similar heavy rainfall events. Hence, we hypothesize that not only the precipitation event, but also seasonal effects have an influence on runoff generation under heavy rainfalls. To quantify runoff generation and the causes of its occurrence, the study site will be analysed using the slope specific, physical, deterministic, hydrological model CATFLOW. Heavy rainfall simulations will be used to study the impact of current land use, alternative cultivation methods and decentralized water retention measures in order to understand potential water retention in the area. The simulation model will be calibrated using field studies such as soil sampling and irrigation tests on the study site and in addition on test fields with integrated water retention measures. Water retention measures also have the advantage of providing increased soil moisture during dry periods, thus enhancing agricultural land quality.
Modeling the 2020 November 29 solar energetic particle event using EUHFORIA and iPATH models
Authors: Ding Zheyi , Wijsen Nicolas , Li Gang , Poedts Stefaan
Published: February 2023

We present the implementation of a coupling between EUropean Heliospheric FORcasting Information Asset (EUHFORIA) and improved Particle Acceleration and Transport in the Heliosphere (iPATH) models. In this work, we simulate the widespread solar energetic particle (SEP) event of 2020 November 29 and compare the simulated time-intensity profiles with measurements at Parker Solar Probe (PSP), the Solar Terrestrial Relations Observatory (STEREO)-A, SOlar and Heliospheric Observatory (SOHO), and Solar Orbiter (SolO). We examined the temporal evolution of shock parameters and particle fluxes during this event and we find that adopting a realistic solar wind background can significantly impact the expansion of the shock and, consequently, the shock parameters. Time-intensity profiles with an energetic storm particle event at PSP are well reproduced from the simulations. In addition, the simulated and observed time-intensity profiles of protons show a similar two-phase enhancement at STA. These results illustrate that modeling a shock using a realistic solar wind is crucial in determining the characteristics of SEP events. The decay phase of the modeled time-intensity profiles at Earth is in good agreement with the observations, indicating the importance of perpendicular diffusion in widespread SEP events. Taking into account the possible large curved magnetic field line connecting to SolO, the modeled time-intensity profiles show a good agreement with the observation. We suggest that the broadly distorted magnetic field lines, which are due to a stream interaction region, may be a key factor in understanding the observed SEPs at SolO.
Preliminary results of a thermal maturity modelling study as a tool for understanding a structural setting – the case of the Fold and Thrust Belt of Western Greece.
Authors: Makri Vagia Ioanna , Schito Andrea , Muirhead David , Oikonomopoulos Ioannis , Bellas Spyridon
Published: February 2023

The Hellenides Fold and Thrust Belt (HFTB) is an arcuate shaped belt whose rocks were deposited in a series of platforms and basins that formed the southern rifted margin of the Apulian microcontinent. Despite a renew interest in the last years due to an international licensing round for the exploration and production of hydrocarbons in Greece, still little is published about its geometry, thermal maturity and hydrocarbon generation timing of the main source rocks hosted in the Mesozoic section. The External-most exposed part of the HFTB consists of the pre-Apulian and the Ionian geotectonic zones from West to East. Being part of the southern passive margin of Tethys from Triassic to Late Cretaceous, the Ionian zone represents a sedimentary basin which was differentiated from the adjacent platforms during the Jurassic rifting and consists of Triassic evaporites, Triassic-Eocene carbonates, and Oligocene-Early Miocene turbidites. The Pre-Apulian zone, as part of the slope of the Apulian platform to the Ionian basin, is made up of Triassic evaporites and up to Miocene carbonates. Organic rich layers are found across the Pre-Apulian and Ionian zones, and chiefly within Mesozoic. Present-day geometries have resulted from the mainly thin-skinned Miocene compressional deformation developed after the collision of the Apulian and Eurasian continental paleomargins. To understand the amount of overburden thickness across the chain, we performed Rock-Eval 6 pyrolysis, Gas Chromatography-Mass Spectrometry, MicroRaman spectroscopy and transmitted light petrography on Mesozoic-Cenozoic source rocks across an ENE-WSW transect in Western Greece where westward migrating intra-Ionian imbricate thrusts are evident. Overall, the data suggest that Cenozoic samples are immature, while Lower Cretaceous and Mid-Upper Jurassic thermal maturity reaches the onset of the oil window and further increases in Lower Jurassic and Triassic successions. Maturity data were used as input parameters to 1D thermal maturity modelling of wells and pseudo-wells across this transect. Model calibration by using present-day heat flow values and a Mesozoic rifting model, suggests that the eroded thickness at each studied location exceeds 1.5km. These erosion estimates better constrain our understanding of the geometry of the belt and the timing of maximum burial.
UV-driven fragmentation of plastics in an aquatic environment: laboratory studies
Authors: Velimirovic Milica , Dumont Géraldine , De Wit Jef , Tirez Kristof , Voorspoels Stefan , Vanhaecke Frank
Published: February 2023

Plastic is considered one of the most practical inventions of the 20th century, providing us with a range of very practical materials. However, due to mismanaged waste the plastic pollution has become persistent in aquatic environments. As the plastic products undergo environmental weathering once released in the aquatic environment, they degrade and are fragmented into a highly heterogeneous group of particles with different sizes (i.e., from centimeter over millimeter and micrometer to nanometer scale), shapes, densities, and chemical compositions. However, due to the lack of suitable analytical methodology, knowledge on degradation and/or fragmentation of plastics to nanoplastics (NPs, 1-1000nm), especially in the aquatic environments is still largely lacking.In the framework of the MS4Plastics project, 15 different plastic materials, including a surgical face mask, different polymer pellets, rubber dust, and plastic powders as common examples of plastics expected to be present in the aquatic system were added to  Milli Q water and exposed to UV-light for 120 hours to better understand plastic degradation and/or fragmentation into NPs. Finally, for detection and size determination of NPs formed after accelerated UV-driven plastic fragmentation in water, dynamic light scattering was used. For a fraction of the samples, asymmetric flow field-flow fractionation (AF4) hyphenated to multi-angle light scattering (MALS) was used as a complementary analytical technique for characterization of NPs.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 101023205. 
Assessment of Impact of air pollution using deep learning-based Air Quality data Model
Authors: Ravikumar Remya , Subbana Nagesh , Singh Alka , Vargas Maretto Raian
Published: February 2023

Air pollution poses a major concern to people’s lives. Over two million Indians are said to lose their life to causes attributed to air pollution (Balakrishnan et al., 2019). Most of this pollution comes from industries closely followed by vehicular pollution, unrestrained emission sources, periodic agricultural pollutants, and household pollution. The air quality data obtained from orbital sensors like Sentinel 5 and 5P, MODIS and Landsat and ground sensors (Central pollution control board sensors, CPCB) provide a large amount of information about the particle pollutants present in the atmosphere. This study explored the fusion of data obtained from ground (CPCB) and orbital sensors to better estimate the air quality parameters like PM2.5, NO2, CO and SO2. The combination of these improved parameters will subsequently enhance the air quality index (AQI) approximation. The region of study is the Indo-Gangetic plain, North India because this region hosts eight out of the top ten most polluted cities worldwide.In this study, we propose a deep neural network-based air quality model by combining fine-grained properties of in-situ (CPCB) data with coarse-grained satellite images. Deep Neural Networks like Convolutional Neural Network (CNN) and Long short-term memory (LSTM) have shown major advantage in solving nonlinear spatio-temporal problems. They can extract valuable contextual features to combine temporal attributes, and model temporal and spatial dependencies accurately. Therefore, we propose the combination of CNN and LSTM models for precise air quality prediction in the Indo Gangetic Plain for the upcoming twenty-four hours based on data acquired on the preceding twenty-four hours.