bluuebunny/crossref_metadata_2025 huggingface dataset:
Grande Comore and Mayotte gas-geochemistry and evidence of deep fluid migration during the 2018-2020 submarine eruption off Mayotte
Authors: Liuzzo Marco , Di Muro Andrea , Rizzo Andrea Luca , Caracausi Antonio , Grassa Fausto , Boudoire Guillaume , Coltorti Massimo , Bénard Bhavani
Published: February 2023

Located within the Mozambique Channel, the Comoros archipelago is situated within a complex geodynamic system of great interest owing to recent volcanic and seismic activity (2018-20), but where little gas geochemistry research has been conducted.Focusing on Grande Comore and Petite Terre, a small islet off the northeast coast of Mayotte, our investigations set out to identify the gas-geochemistry characteristics of the islands, and explore any potential influence from the then ongoing unrest and/or volcanic activity.Geochemical surveys included measurements of soil CO2 flux on both islands, and gas sampling from fumarolic areas at Karthala volcano (Grande Comore) and two bubbling areas at Petite Terre, with the aim of determining the chemical and isotopic characteristics of the main gases (CO2, CH4, He, Ne, Ar) and equilibrium temperatures of the hydrothermal system at Petite Terre.δ13C values of soil CO2 emissions highlight evidence of a low magmatic contribution at Grande Comore, while a significantly higher contribution is evident at Petite Terre. 3He/4He data are consistent with average values of fluid inclusions for both Grande Comore and Petite Terre rocks, and are fixed at low value ranges (4.7≤Rc/Ra≤5.9 and 5.3≤Rc/Ra≤7.5 respectively). The gases detected at the two sites of Petite Terre primarily reflect the signature of deep gases in terms of geochemical tracers such as R/Ra and δ13C in CO2.  At one of the two emission sites at Petite Terre, namely the meromictic lake Dziani Dzaha, the gases are relatively more variable in relative proportion of CO2, CH4  and C isotopes; at this specific site, a significant influence from microbial activity is evidenced.Our results allow us to infer that the general degassing characteristics between the two islands are similar. They also shed light on their reciprocal differences, which may either be attributable to local specifics within Petite Terre, or to different states of volcanic activity between Grande Comore and Petite Terre at the time of the surveys, the latter being a consequence of fluid migration to the mainland of Mayotte during the offshore submarine activity (2018-20).The outcomes of this work provide a necessary step towards filling gaps in the knowledge of gas-geochemistry in Comoros, and contribute potential support for volcanic and environmental monitoring programmes.
Open Earth Engine Toolbox, code goodies and extension for Google Earth Engine
Authors: Gravey Mathieu
Published: February 2023

The Open Earth Engine Toolbox (OEET) is an innovative and highly effective suite of tools that makes it easier than ever to work with Google Earth Engine. Comprised of two main components - the Open Earth Engine Library (OEEL) and the Open Earth Engine Extension (OEEex) - the OEET is a true game-changer for anyone working in the field of geospatial analysis and data processing.The OEEL is a set of JavaScript code libraries that provide a wide range of functions and capabilities for working with Earth Engine. From advanced filtering techniques such as the Savitzky-Golay and Otsu algorithms, to powerful visualization tools like north arrows, map scales, mapshots… the OEEL has everything you need to get the most out of Earth Engine. And with a convenient Python wrapper, it's easy to integrate the OEEL into your existing workflow, scripts or notebooks.But the OEEex is where the OEET really shines. This Chrome extension is designed you to work in tandem with the OEEL, unlocking a host of additional features and capabilities. One of the standout features of the OEEex is its ability to all run tasks in a single step. This is particularly useful for those working with large datasets or for those who need to perform the same tasks repeatedly. With the OEEex, you can simply set up your tasks and then let the extension handle the rest, saving you time and effort of clicking on each. The OEEex also offers a range of customization options for the interface. These include the ability to switch to a dark mode, which can be easier on the eyes during long work sessions, as well as the ability to adjust font sizes to suit your personal preference. It allows to utilize Plotly within Earth Engine to get beautiful figure, and much more.Overall, the OEET is an essential tool for anyone looking to get the most out of Google Earth Engine. Its powerful JavaScript libraries, convenient Python wrapper, and feature-rich Chrome extension make it the go-to choice for geospatial analysis and data processing.
Glacier and snow melt contributions to streamflow on James Ross Island, Antarctic Peninsula
Authors: Nedělčev Ondřej , Matějka Michael , Láska Kamil , Engel Zbyněk , Kavan Jan , Jeníček Michal
Published: February 2023

Antarctic Peninsula region experienced a rapid increase in air temperature during the second half of the 20th century. Although the warming was interrupted in the first decades of the 21st century, future climate projections predict that air temperature will increase significantly until the end of the 21st century in this area. Changes in air temperature have large impact on runoff process, especially in proglacial environment. Even though these changes affects both terrestrial and marine ecosystems, runoff generation in Antarctic Peninsula region is still poorly understood. Therefore, we analysed runoff process in small, partly glaciated catchment on James Ross Island, which belongs to the largest deglaciated area in Antarctica. Our objective was to 1) describe runoff variability in this area and 2) to estimate glacier, snow, and rain contributions to runoff in relation to climate variability.Due to limited discharge measurements, we used semi-distributed bucket-type HBV model to simulate runoff process in years 2010–2020 in a daily temporal resolution. Input data for the model were time series of in situ measured air temperature, and simulated precipitation. Precipitation was simulated by the Weather Research and Forecasting model driven by ERA5 reanalysis. The HBV model was calibrated against measured daily discharge from six weeks long period in February and March 2018, and seasonal ablation measurements from years 2014–2020.The results showed that 93% of the annual runoff occurred from October to May. The highest mean monthly runoff occurred in the second half of summer due to combination of strong glacier and snow melt. Additionally, large runoff was found in November which was caused by melt-out of seasonal snow cover. The major part (53%) of runoff originates from snow cover, 41% originates from glacier and only 6% from rainfall. Snowmelt runoff dominated during winter (with overall low absolute values of runoff) and in autumn. In summer, snowmelt runoff was almost the same as glacier runoff. In autumn, contribution of glacier to total runoff was slightly higher than contribution of snow. Contribution of snow to total runoff was higher in colder years with higher precipitation. In contrast, melting glacier contributed more during warmer years with less precipitation.
An abrupt transition in the Antarctic sea ice–ocean system
Authors: Haumann F. Alexander , Massonnet François , Holland Paul R. , Bushuk Mitchell , Maksym Ted , Hobbs Will , Meredith Michael P. , Cerovečki Ivana , Lavergne Thomas , Meier Walter N. , Raphael Marilyn , Stammerjohn Sharon
Published: February 2023

Over the past decade, Antarctic sea ice extent exhibited a sequence of record maxima, followed by a rapid decline in 2015/16, and record minima since. In this presentation, we show that this sudden and remarkable ice loss marks an abrupt transition from a high to a low ice state that cannot be explained by year-to-year variability. Instead, it is most likely associated with a longer term variability arising from ice–ocean feedbacks. The abrupt transition was preceded by a multi-decadal increase in persistence and variance of the sea ice anomalies, an increasing upper Southern Ocean density stratification, and an accumulation of heat at the subsurface; suggesting a decoupling of the surface from the subsurface ocean. During this period, the sea ice anomalies shifted from being structured predominantly regionally and seasonally to a largely circumpolar and interannual regime. In 2015/16, the upper ocean density stratification in the ice-covered region suddenly weakened, leading to a release of heat from the subsurface, contributing to the sea ice decline during winter. Our analysis suggests that the sudden sea ice loss in 2015/16, and the persisting low ice conditions since, arose from a systematic change in the physical state of the coupled circumpolar ice–ocean system. This change will have wide implications for global climate, ecosystems, and the Antarctic Ice Sheet.
A simple coupled assimilation approach for improved initialization of decadal climate predictions
Authors: Kruschke Tim , Karami Mehdi Pasha , Docquier David , Schenk Frederik , Fuentes Franco Ramon , Willén Ulrika , Wang Shiyu , Wyser Klaus , Fladrich Uwe , Koenigk Torben
Published: February 2023

We introduce a simple data assimilation approach applied to the coupled global climate model EC-Earth3.3.1, aiming at producing initial conditions for decadal climate hindcasts and forecasts. We rely on a small selection of assimilated variables, which are available in a consistent manner for a long period, providing good spatial coverage for large parts of the globe, that is sea-surface temperatures (SST) and near-surface winds.Given that these variables play a role directly at or very close to the ocean-atmosphere interface, we assume a comparably strong cross-component impact of the data assimilation. Starting from five different free-running CMIP6-historical simulations in 1900, we first apply surface restoring in the model’s ocean component towards monthly means of HadISST1. After integrating this five-member ensemble with only assimilating SST for the period 1900-1949, we start additionally assimilating (nudging) 6-hourly near-surface winds (vorticity and divergence) taken from the ERA5 reanalysis from 1950 onwards. To mitigate the risk of model drifts after initializing the decadal predictions and to account for known instationary biases of the model, we assimilate anomalies of all variables that are calculated based on a 30-year running mean.By assimilating near-surface data over several decades before entering the actual period targeted by the decadal hindcasts/forecasts for CMIP6-DCPP, we expect the coupled model to be able to ingest a significant share of observed climate evolution also in deeper ocean layers. This would then potentially serve as a source of predictive skill on interannual-to-decadal timescales.We show that the presented assimilation approach is able to force the coupled model’s evolution well in phase with observed climate variability, positively affecting not only near-surface levels of the atmosphere and ocean but also deeper layers of the ocean and higher levels of the atmosphere as well as Arctic sea-ice variability. However, we also present certain problematic features of our approach. Two examples are significantly strengthened low-frequency variability of the AMOC and a wind bias resulting into generally reduced evaporation over ocean areas.
Status and first results of the MURAVES experiment at Mt. Vesuvius
Authors: Al Moussawi Marwa ,   MURAVES Collaboration
Published: February 2023

The MURAVES experiment, whose acronym stands for MUon RAdiography of VESuvius, aims at the imaging of the internal structure of the summit of Mt. Vesuvius through muography, i.e. the absorption of muons naturally produced by cosmic rays. Though presently quiescent, this volcano carries a dramatic hazard in its highly populated surroundings. The challenging measurement of the rock density distribution in its summit by muography, in conjunction with data from other geophysical techniques, can help the modeling of possible eruptive dynamics. The MURAVES apparatus consists of an array of three independent and identical muon trackers, two pointing towards the volcano and one towards the free sky (to collect reference data), each of them made of four 1m2 active area XY tracking planes made of plastic scintillators. In each muon tracker, a 60 cm thick lead wall between the two downstream planes ensures rejection of background from low energy muons. MURAVES has been acquiring data since 2019. We will present a description of the muon trackers, as well as the preliminary results from the analysis of a sub-set of the data samples collected thus far, focusing in particular on an early measurement of density asymmetry.In addition, we will report on a number of simulation studies that allow us to investigate the effects of the experimental constraints and to compare our simulated data with the actual observations.
Crustal Deformation of Biga Peninsula and Structural Controls on Porphyry Cu-Au and Epitermal Au Mineralization in Kirazlı Gold Deposit (Türkiye)
Authors: Çam Mehmet , Kuşcu İlkay , Kaymakcı Nuretdin , Karcı Mehtap
Published: February 2023

Kirazlı porphyry Cu-Au and epitermal Au mineralization is located in Biga peninsula where the region hosts numerious porphyry- and epithermal- style Au mineralizations within the Tethyan orogenic belt. Crustal deformation in the region is resulted by Cretaceous collusion during the closure of northern branch of Neotethys Ocean, related subduction, post-collusion, Cenozoic extension and following dextral strike-slip deformation regime which is emerged during the westward migration of Anatolian plate. The study includes regional fault mapping, slip data collection from regonal and district scale faults for paleostress analysis, oriented surface sampling of vein hosted deformational zones and micro-structural thin section examinations of oriented samples. Paleostress findings and fault orientations indicates two seperate character of deformations as nearly E-W trending extensional fault systems and subsequent NE-SW striking, steeply dipping dextral strike-slip faults with accompanying NNW-SSE trending left-lateral strike slip and ENE-WSW trending dextral strike-slip and oblique-slip faults. Later tectonic phase related with N-E Dextral strike-slip faults establishes the main deformational trend with accompanying district scale  R (synthetic) ENE-WSW trending dextral and NNW-SSE trending R' (antithetic) sinistral strike-slip faults. Slip data related to  E-W and ENE-WSW faults indicate that these faults are subjected to both N-S trending extensional and NE-SW trending dextral strike-slip tectonic regime. The petrographic and textural studies of oriented thin sections resulted in identification of two predominant vein directions as ENE-WSW and NNW-SSE of porphyry mineralization within the project area. ENE-WSW trending syntaxial, streched-blocky quartz bearing veins indicates multiple N-S extension and crack-seal events and postdated by NNW-SSE trending quartz veins. Also the veins with same orientation which were observed during field studies share similar orientations.This study presents the early results off Ph.D. thesis "Crustal Extension and its Relationship to Porphyry Cu-Au and Epithermal Au Mineralization in the Kirazlı Gold Deposit (Çan, Çanakkale, Türkiye)" and supported by Alamos Gold Inc..
Utilizing optical flow technique to understand plasma convection
Authors: Gallardo-Lacourt Bea , Goodwin Lindsay , Gillies D. Megan , Kepko Larry , Spanswick Emma , Reyes Pablo , Donovan Eric
Published: February 2023

Plasma convection is a fundamental process of mass and energy transport within our solar system. In Earth’s magnetosphere, convection models often underestimate, or even fail to identify the contributions of dynamic ionospheric mesoscale (10s-100s km) structures that are responsible for significant energy transfer within the magnetosphere-ionosphere coupled system. The most used convection model relies on data from radars, which operates on spatial scales of approximately 50 km, with a temporal resolution of 2 minutes. In contrast, modern red-line all-sky cameras have a spatial resolution on the order of 1 km and temporal resolution of 3 s. These cameras respond to low energy precipitating electrons, which makes them sensitive tracers of magnetospheric convection, and sensitive to mesoscale structures that may be missed by radars. In recent years, the deployment of new cameras has expanded the coverage to include most of the auroral oval and polar cap above the North American continent. Despite their potential for monitoring and studying ionospheric convection, currently only rudimentary techniques have been applied to measure the motion of these optical structures. In this work, we show initial results of optical flow calculations to analyze the motion of optical structures observed with the new red-line all-sky cameras. Optical flow calculations represent the apparent motion of objects in consecutive frames. The result of this technique provides two-dimensional flow fields, which has enabled us to enhance our understanding of ionospheric electric fields. Finally, perform a validation analysis by comparing the optical flow calculations and incoherent scatter radar measurements.
Joint Interpretation of Multi-Frequency Ground Penetrating Radar and Ultrasound Data for Mapping Cracks and Cavities in Tree Trunks
Authors: Parnow Saeed , Lantini Livia , Uzor Stephen , Alani Amir M. , Tosti Fabio
Published: February 2023

As the Earth's lungs, trees are a natural resource that provide, amongst others, food, lumber, and oxygen. Therefore, monitoring these wooden structures with non-destructive testing (NDT) techniques such as ground penetrating radar (GPR) and ultrasound can provide valuable information about inner flaws and decays, which is an essential step for tree conservation.  In recent years, GPR and ultrasound have been used to delineate the interior architecture of tree trunks [1-3]. However, more research is required to improve results and consequently have a more reliable interpretation. Due to limitations in depth penetration and signal-to-noise ratio [4], these approaches have a limited capacity for resolving features. The use of gain functions and higher frequencies to compensate for wave attenuation may exaggerate events and reduce resolution, respectively.In this context, an integration between GPR multi-frequency and ultrasound data can be used to address this issue. Data were collected on a tree trunk log at the Faringdon Centre for Non-Destructive Testing and Remote Sensing using two high-frequency GPR systems (2GHz and 4GHz central frequencies) and an ultrasound (supporting a wide range of transducers from 24 kHz up to 500 kHz) testing equipment. Internal features of interest in terms of extended perimetric air gaps at the bark-wood interface, natural cracks and small artificial cavities were investigated through electromagnetic and mechanical waves. After compilation of data, a joint interpretation strategy for data analysis is developed. The processed data were mapped against the cut sections of the tree for validity purposes.Although study of stand tree trunks would be more challenging, the findings of this research may be applied for wood timbers and pave the way to future research for living tree trunks. AcknowledgementsThis research was funded by the Vice-Chancellor’s PhD Scholarship at the University of West London. References[1] Arciniegas, A., et al., Literature review of acoustic and ultrasonic tomography in standing trees. Trees, 2014. 28(6): p. 1559-1567. [2] Giannakis, I., et al., Health monitoring of tree trunks using ground penetrating radar. IEEE Transactions on Geoscience and Remote Sensing, 2019. 57(10): p. 8317-8326.[3] Espinosa, L., et al., Ultrasound computed tomography on standing trees: accounting for wood anisotropy permits a more accurate detection of defects. Annals of Forest Science, 2020. 77(3): p. 1-13.[4] Tosti, F., et al., The use of GPR and microwave tomography for the assessment of the internal structure of hollow trees. IEEE Transactions on Geoscience and Remote Sensing, 2021. 60: p. 1-14. 
Multidisciplinary approach to reconstruct the pathways of the CO2 nonvolcaning degassing in the thermal springs of Contursi and Oliveto Citra sector (southern Appennines, Italy)
Authors: Di Giuseppe Maria Giulia , Ciarcia Sabatino , De Paola Claudio , Fabozzi Carmela , Isaia Roberto , Troiano Antonio , Vitale Stefano
Published: February 2023

The southern Apennines are a fold-and-thrust belt characterized by the superpositions of different thrust sheets. The orogenic construction defined by thin- and thick-skinned tectonics occurred from the Paleocene to the early Pleistocene. In this orogen, evidence of nonvolcanic degassing is widely reported. The orogenic chain hosts the Mefite d'Ansanto (MdA) vent, the most significant nonvolcanic natural emission of low-temperature CO2 on Earth. Other degassing areas are located in the Sele River Valley, where several vents are aligned along major faults, including the thermal springs of Contursi and Oliveto Citra (COC).Different investigations on these nonvolcanic emissive structures mark a close relation between degassing phenomena and tectonics, evidencing a likely dominant crustal gas origin for the COC vent. In any case, poor information is available about the characteristics of the CO2 reservoir (including the geometry and depth) and the fluid's rising pathways.Different surveys have been performed, applying a multidisciplinary approach, including innovative methodologies, aiming to reconstruct the geometry of the shallow degassing pathways and investigate how the different geological and tectonic architecture influences the CO2 seeping and surficial degassing processes. The structures that convey and favour the upward gas migration, seeping and degassing have been imaged using geophysical and structural investigations.Electrical Resistivity (ERT) and Induced Polarization (IP) tomographies, combined with Self-Potential (SP), Magnetic (Mag), and PH mapping have been performed in correspondence with the most degassing part of the COC area. The joint acquisition of such a multiparametric dataset ended in a better-constrained interpretation of the different detected anomalies. Furthermore, the obtained results allowed us to construct different geophysical maps and geological cross-sections of the investigated area and develop a model of the degassing vents area, highlighting the role of reconstructed lithological and structural settings in the shallow leaking processes.
A likelihood analysis of the Global Flood Monitoring ensemble product
Authors: Krullikowski Christian , Chow Candace , Wieland Marc , Martinis Sandro , Chinni Marco , Matgen Patrick , Bauer-Marschallinger Bernhard , Roth Florian , Wagner Wolfgang , Stachl Tobias , Reimer Christoph , Briese Christian , Salamon Peter
Published: February 2023

Flooding is a natural disaster that can have devastating impacts on communities and individuals, causing significant damage to infrastructure, loss of life, and economic disruption. The Global Flood Monitoring (GFM) system of the Copernicus Emergency Management Service (CEMS) addresses these challenges and provides global, near-real time flood extent masks for each newly acquired Sentinel-1 Interferometric Wide Swath Synthetic Aperture Radar (SAR) image, as well as archive data from 2015 on, and therefore supports decision makers and disaster relief actions. The GFM flood extent is an ensemble product based on a combination of three independently developed flood mapping algorithms that individually derive the flood information from Sentinel-1 data. Each flood algorithm also provides classification uncertainty information as flood classification likelihood that is aggregated in the same ensemble process. All three algorithms utilize different methods both for flood detection and the derivation of uncertainty information.The first algorithm applies a threshold-based flood detection approach and provides uncertainty information through fuzzy memberships. The second algorithm applies a change detection approach where the classification uncertainty is expressed through classification probabilities. The third algorithm applies the Bayes decision theorem and derives uncertainty information through the posterior probability of the less probable class. The final GFM ensemble likelihood layer is computed with the mean likelihood on pixel level. As the flood detection algorithms derive uncertainty information with different methods, the value range of the three input likelihoods must be harmonized to a range from low [0] to high [100] flood likelihood.The ensemble likelihood is evaluated on two test sites in Myanmar and Somalia showcasing the performance during an actual flood event and an area with challenging conditions for SAR-based flood detection. The findings further elaborate on the statistical robustness when aggregating multiple likelihood layers.The final GFM ensemble likelihood layer serves as a simplified appraisal of trust in the ensemble flood extent detection approach. As an ensemble likelihood, it provides more robust and reliable uncertainty information for the flood detection compared to the usage of a single algorithm only. It can therefore help interpreting the satellite data and consequently to mitigate the effects of flooding and accompanied damages on communities and individuals.
Scale-dependent fracture patterns and flow in low-enthalpy geothermal targets: the role of diagenesis and contingent nodes
Authors: Laubach Stephen , Forstner Stephanie
Published: February 2023

Under diagenetic conditions between ca. 50 ℃ to 250 ℃ the systematics of cement precipitation and differential infill makes network porosity, and thus permeability and strength, scale and thermal history dependent. Using examples of regional opening-mode fractures in sandstones from the Cambrian Flathead Formation, Wyoming, a low-enthalpy geothermal outcrop analog, we show that quartz deposits preferentially fill fractures up to ca. 0.05 mm wide with a transition from mostly sealed to mostly open fractures over a narrow size range of opening displacements from 0.05 to 0.1 mm. Scale- and diagenesis- dependent connectivity can be described using use rule-based node descriptions to rapidly measure diagenesis sensitive connections within the context of current field practice.  In our example, although networks have trace connectivity, effective connectivity for fluid flow is greatly reduced by quartz cement. Near some faults, trace connectivity increases as initially wide porous fractures preferentially shear and wing cracks form, increasing fracture intersections (Y-nodes). However, pore space is lost due to the development of quartz-cemented microbreccia. Macro-scale trace connectivity increases, but porous connectivity diminishes and thus potential for fluid flow is markedly lower. We illustrate how diagenesis-sensitive contingent nodes can be used to extrapolate permeability estimates to locations having different thermal histories.
Deep Learning for Verification of Earth's surfaces
Authors: Choulga Margarita , Kimpson Tom , Chantry Matthew , Balsamo Gianpaolo , Boussetta Souhail , Dueben Peter , Palmer Tim
Published: February 2023

Ever increasing computing capabilities and crave for high-resolution numerical weather prediction and climate information are specially interesting for the representation of Earth surfaces. Knowledge of accurate and up-to-date surface state for ecosystems such as forest, agriculture, lakes and cities strongly influence the skin temperatures, turbulent latent and sensible heat fluxes providing the lower boundary conditions for energy and moisture availability near the surface. A quick and automatic tool to assess the benefits of updating different surface fields, that makes use of a neural network regression model trained to simulate satellite observed surface skin temperatures, was developed. This tool was deployed to determine the accuracy of several global datasets for lakes, forest, and urban distributions. Comparison results will be shown. The neural network regression model has proven to be useful and easily adaptable to assess unforeseen impacts of ancillary datasets, also detecting erroneous regional areas over the globe, proving to be a valuable support to model development. 
Dynamic damage in dry and wet rocks monitored by ultra-fast synchrotron imaging
Authors: Renard Francois , Cordonnier Benoit , Doan Mai-Linh , Fondriest Michele , Lukic Bratislav , Prastyani Erina
Published: February 2023

During earthquake propagation, a shock wave damages rocks at the rupture tip, creating numerous microfractures and altering the mechanical properties of fault zone rocks. This damage, which occurs dynamically at the millisecond time scale, controls rock strength during earthquake slip that occurs in the wake of rupture propagation. How the presence of water and the initial porosity of the rock control damage during high strain rate deformation remains an open question. We have performed a series of shock experiments using a split Hopkinson pressure bar apparatus installed at the European Synchrotron Radiation Facility. Using two ultra-fast cameras synchronized with the X-ray bunches of the synchrotron; we imaged deformation with microsecond time resolution on centimetre-scale core samples during shock wave damage. We deformed dry and water saturated low porosity Westerly granite and porous Berea sandstone samples. Several samples were surrounded by a thin aluminium jacket allowing recovering them after deformation and image them using X-ray microtomography with micrometre spatial resolution. Results confirm previous studies that have shown that rock pulverization occurs above a threshold strain rate produced by the shock wave. Water saturated samples are consistently weaker than dry samples as they pulverize under lower peak stress. Analyses of rock microstructure acquired using the ultrafast cameras and X-ray microtomography data shed light on the micro-mechanisms of damage production. Either the entire sample pulverized (Westerly granite) or a compaction of the sample occurred before shear zones were dynamically produced (Berea sandstone). These results demonstrate fundamental differences in dynamic damage production in crystalline and porous dry and wet rocks. Our data unravel mechanisms of gouge production before any significant slip has occurred on a fault, which control the shear strength during earthquake slip.
A comprehensive observational database of deformation at global volcanoes for machine learning applications
Authors: Shen Lin , Hooper Andrew , Lazecky Milan , Gaddes Matthew , Ebmeier Susanna
Published: February 2023

A key indicator of potential and ongoing volcanic activity is deformation of a volcano's surface due to magma migrating beneath. The European Sentinel-1 radar archive now contains a large number of examples of volcano deformation, yet the vast majority of subaerial volcanoes are not well monitored. We therefore aim to systematically extract all deformation signals at volcanoes globally, including smaller scale signals associated with processes such as landslides and local changes in hydrothermal systems, which can provide a basis for machine learning approaches to automatically classify and potentially forecast deformation.We have developed an approach to automatically derive high-resolution displacement time series centred on each volcano. To avoid the loss of decorrelated signal in areas of glacial coverage, winter snow and heavy vegetation, we build a highly redundant small baseline network of interferograms tailored to each volcano using coherence tests. We implement an improved phase unwrapping algorithm that separately unwraps signals at different spatial scales, to improve results in decorrelating areas. To mitigate the effect of phase propagation through the atmosphere, we provide multiple atmospheric correction methods, including a spatially-varying scaling method that uses interferometric phase to refine the interpolation of a weather model in time and space.The processed products, stored in a database with annotated metadata (VolcNet), are available for the further interpretation. We show here the volcanic unrest at a large number of volcanoes taken from the database, detected using a machine learning algorithm LiCSAlert. We also show a statistical analysis based on the processed time series for the assessment of volcanic risk.
Mirco-Geomorphology Differences Between Channelized Debris Flow with Hillslope Debris Flow
Authors: Chen Tien-Chien , Hung Yang
Published: February 2023

The micro geomorphology characteristics of 47 hillslope debris flow (HDF) and 16 channelized debris flow (CDF) events were studied to explore the difference between HDF and CDF. In Taiwan, debris flow torrents are classified into CDF and HDF two types. CDF watershed consists of tributaries and gullies, in which one or multi tributaries might occur the debris flow then inducing the CDF. HDF is located upstream of the watershed and caused by a landslide on the slope and transforming into HDF. The result shows that the factors of CDF are larger than those of HDF including the watershed area, initiation region, length of the transport segment, and elevation differences of the transport segment. The gradient of the riverbank slope is similar between CDF and HDF. However, the channel gradient of the transport segment of HDF is higher than that of CDF. The gradient ratio between the channel gradient and the average gradient of the riverbank slope on the transport segment of CDF is smaller than the gradient ratio of HDF, revealing that CDF valley erosion is higher than HDF valley. This study attempts to establish the criteria for the interpretation of CDF and HDF and explores the differences between the two in the topographic characteristics.
Towards the European Green Deal Data Space
Authors: Gutierrez David Marta , Dietrich Mark , Raczko Nevena , Denvil Sebastien , Santoro Mattia , Chatzikyriakou Charis , Borejko Weronika
Published: February 2023

The European Commission has a program to accelerate the Digital Transition and is putting forward a vision based on cloud, common European Data Spaces and AI. As the data space paradigm unfolds across Europe, the Green Deal Data Space emerges. Its foundational pillars are to be built by the GREAT project. Data Spaces will be built over federated data infrastructures with common technical requirements (where possible) taking into account existing data sharing initiatives. Services and middleware developed to enable a federation of cloud-to-edge capacities will be at the disposal of all data spaces.GREAT, the Green Deal Data Space Foundation and its Community of Practice, has the ambitious goal of defining how data with the potential to help combat climate and environmental related challenges, in line with the European Green Deal, can be shared more broadly among many stakeholders, sectors and boundaries, according to European values such as fair access, privacy and security. The project will consider and incorporate community defined requirements and use case analyses to ensure that the resulting data space infrastructure is designed and built with and for the users. An implementation roadmap will guide the efforts of multiple actors to converge toward a blueprint technical architecture, a data governance scheme that enables innovative business cases, and an inventory of high value datasets, that will enable proof of concept, implementation and scale-up of a minimum viable green deal data space.This roadmap will identify the resources and other key ingredients needed for the Green Deal Data Space to be successful. Data sharing by design and data sovereignty are some of the main principles that will apply from the early stages ensuring cost effective and sustainable infrastructures that will drive Europe towards a single data market and green economic growth. This talk will present how to engage with the project, the design methodology, progress towards the roadmap for deployment and the collaborative approach to building data spaces in conjunction with all the sectoral data spaces and the Data Space Support Centre.
FARM: Combined surface flux transport and helioseismic Far-side Active Region Model
Authors: Heinemann Stephan G. , Yang Dan , Pomoell Jens , Arge Charles N. , Jones Shaela I. , Gizon Laurent
Published: February 2023

Synoptic magnetic field data usually serves as the boundary condition for simulations of the global magnetic field; however, it has been shown that these data suffer from an “aging effects” as the longitudinal 360° information can only be obtained over the course of one solar rotation. To avoid this, we use advanced magnetograms produced by feeding near-side HMI/SDO magnetograms and far-side helioseismic active regions into a modified surface flux transport model to improve the modeling of the far-side magnetic configuration. This allows for a more accurate description of the state of the global magnetic field and thus for an improved forecasting of solar wind parameters. We use potential field source surface (PFSS) and WSA modeling as well as the EUropean Heliospheric FORecasting Information Asset (EUHFORIA) to derive the coronal magnetic field configuration and the heliospheric solar wind structure as well as discuss the changes caused by the implementation of far-side active regions into magnetic field maps. Modeled solar wind results are found to be in good agreement with far-side in-situ measurements taken by various instruments. We can show the importance of considering not only the solar near-side but also the far-side to accurately model the heliosphere in which solar transients are propagated.
Methane flux measurements above a Scots Pine forest in Austria
Authors: Scholz Katharina , Hammerle Albin , Wohlfahrt Georg
Published: February 2023

Forests play an important role in the exchange of greenhouse gases like CO2 and CH4 between the biosphere and the atmosphere. Although fluxes vary depending on biotic and abiotic factors like ecosystem composition and climatic conditions, forests generally are a sink for CO2. For CH4, forests with well-drained soils are considered a sink due to the oxidation of CH4 within those soils. However, recent study results indicate that CH4 emissions from trees may offset this soil CH4 sink, resulting in a lower sink strength or even source at the ecosystem level.To quantify the net CH4 ecosystem exchange of a temperate needleleaf forest, we started CH4 flux measurements above a Scots Pine forest at the ‘FAIR’ research site in Austria in August 2022 using the eddy covariance method. The results show very small fluxes with nighttime fluxes close to zero while fluxes during the day are more variable. Overall, the site is a very small sink for CH4 at most. This site is temporally snow-covered during winter. As snowmelt increases soil moisture, we hypothesize that snowmelt in spring may further reduce the ecosystem CH4 sink strength. Here, besides presenting flux results, we will also discuss methodical challenges of measuring very small fluxes.
Evaluation of Different Water Management Practices for the Sustainable Use of Groundwater Resources in the Konya Closed Basin
Authors: Yoloğlu Onur Cem , Uygur İzel , Copty Nadim K. , Daloğlu Çetinkaya İrem , Saysel Ali Kerem
Published: February 2023

The Konya Closed Basin (KCB) in central Turkey is a vast fertile plain that is one of the major agricultural regions of the country and critical to its food supply and security. KCB is characterized by a semi-arid climate, with mean annual precipitation of 379 mm. Since most of the rain occurs in the winter months outside the agricultural season, groundwater is used extensively for irrigation. In recent years, groundwater levels have experienced sharp declines due to the expansion of irrigated lands and the switch to more water-demanding crops. This problem is exacerbated by a large number of unregulated groundwater extraction wells. A regional numerical surface-subsurface water flow model based on the UZF1-MODFLOW computer program was developed for the science-based management of this vital resource. The model simulates transient vertical flow through the vadose zone and groundwater flow through the underlying aquifer system. Because of the lack of direct measurements of groundwater abstraction rates, the time-dependent monthly rate of groundwater abstraction was estimated indirectly based on crop water requirements and historical land allocation for the different crops. The hydrogeology of the site was characterized from borehole data and conducted pumping tests. Historical groundwater level observations between the years 2000-2020 were used to calibrate the model. The key calibration parameter was irrigation efficiency. The challenges of developing and calibrating a regional water flow model are discussed. The calibrated model was then used to simulate the impact of different groundwater conservation scenarios: a slow and a fast transition to less water-demanding crops and the adoption of an optimized cropping pattern. The scenarios are evaluated against the business-as-usual scenario that assumes historical water demand trends remain unchanged. The results underline the urgent need to consider a holistic approach to address the water deficit of the basin. Overall, the model can help policy and decision-makers explore more efficient and sustainable groundwater management practices. This work was developed under the scope of the InTheMED project. InTheMED is part of the PRIMA program supported by the European Union’s HORIZON 2020 research and innovation program under grant agreement No 1923.
Extreme temperature events for the past 19 years in the McMurdo Dry Valleys, Antarctica linked to mesoscale meteorological variability
Authors: Bendix Nielsen Eva , Katurji Marwan , Zawar-Reza Peyman , Meyer Hanna
Published: February 2023

The McMurdo Dry Valleys (MDVs) in Antarctica have a unique environment classified as a hyper-arid desert with glacier runoff being the main source of liquid water. Previous studies have identified winds as the controlling factor of the climate in this region and especially the occurrence of foehn induced warming. Episodic foehn warming during the austral summer can contribute to above freezing temperatures sustained for multiple days. Years with extreme glacial runoff leading to flooding have been correlated with a higher occurrence of foehn induced warming events. Understanding the temporal availability of meltwater caused by extreme meteorological events is highly important since it is a dependant variable to the functioning of the area’s fragile ecosystem. Synoptic scale circulations in the surrounding Ross Sea Region are a driving factor for the occurrence of foehn warming in the MDVs with the local mesoscale meteorology modulating the spatiotemporal variability of the foehn-induced near-surface warming. AntAir ICE, a newly developed daily mean near surface air temperature dataset with a spatial grid resolution of 1 km2 has proven capable of capturing these mesoscale temperature variabilities for multiple seasons within the complex topography of the MDVs. A case study on the 2nd of January 2020 where the maximum temperature measured in a Lake Vanda automatic weather station was above +9 degrees Celsius with multiple valleys experiencing foehn induced warming, displayed a clear warming signal for the MDVs in AntAir ICE. The atmospheric dynamic analysis from the numerical weather prediction model the Antarctic Mesoscale Prediction System (AMPS) indicated a clear foehn signature. This event was linked to a meso-low located in the Ross Sea which was detected in the climate re-analysis ERA5 mean sea level pressure dataset. By confidently identifying these warming events within the MDVs where there is a relatively high availability of Automatic Weather Stations and AMPS predictions, has allowed for further exploration of extreme sustained warming and potentially foehn induced warming along the terrestrial coastal margin of Antarctica. Using AntAir ICE, warming events during the austral summer season from November to February for the period 2003 to 2021 with sustained daily mean temperatures above freezing for multiple days have been identified for the Ross Sea Region. This study aims at capturing the mesoscale meteorological and climatological variability for multiple seasons within the Ross Sea Region, while linking these extreme warming events to larger scale circulation patterns can allow for understanding local extreme events in context of shifting large scale circulation drivers.
Comparative MMS analysis of Markov turbulence in the magnetosheath on kinetic scales
Authors: Macek Wiesław M. , Wójcik Dariusz
Published: February 2023

We apply Fokker-Planck equation to investigate processes responsible for turbulence in space plasma. In our previous studies, we have shown that turbulence in the inertial range of hydromagnetic scales exhibits Markov properties [1,2]. We have also extended this statistical approach on much smaller scales, where kinetic theory should be applied. Namely, we have already obtained the results of the statistical analysis of magnetic field fluctuations in the Earth’s magnetosheath based on the Magnetospheric Multiscale (MMS) mission [3]. Here we compare the characteristics of turbulence behind the bow shock, inside the magnetosheath, and near the magnetopause. We check whether the second order approximation of the Fokker-Planck equation leads to kappa distribution of the probability density function provided that the first Kramers-Moyal coefficient is linear and the second term is quadratic, describing drift and diffusion correspondingly, which is a generalization of Ornstein-Uhlenbeck process. In some cases the power-law distributions are recovered. For moderate scales we have the kappa distributions described by various peaked shapes with heavy tails. In particular, for large values of the kappa parameter this is reduced to the normal Maxellian distribution. The obtained results on kinetic scales could be important for a better understanding of the physical mechanism governing turbulent systems in laboratory and space.Keywords: Kinetic scales, Markov processes, MMS probe, Plasmas, Solar wind, Turbulence.Acknowledgments. This work has been supported by the National Science Centre, Poland (NCN), through grant No. 2021/41/B/ST10/00823.References1. Strumik, M., & Macek, W. M. 2008a, Testing for Markovian character and modeling of intermittency in solar wind turbulence, Physical Review E, 78, 026414, doi=10.1103/PhysRevE.78.026414.2. Strumik, M., & Macek, W. M. 2008b, Statistical analysis of transfer of fluctuations in solar wind turbulence, Nonlinear Processes in Geophysics, 15, 607-613, doi=10.5194/npg-15-607-2008.3. Macek, W. M., Wójcik, D. & Burch, J. L. 2023, Magnetospheric Multiscale observations of Markov turbulence on kinetic scales, arXiv=2211.05098, Astrophysical Journal, https://doi.org/10.3847/1538-4357/aca0a0.. 
Sampling microplastics in estuarine environments: lessons learned from suspended sediment dynamics and perspectives.
Authors: Defontaine Sophie , Jalon-Rojas Isabel
Published: February 2023

Standardized sampling methods and protocols are essential to facilitate the comparison of studies on plastic pollution and to advance knowledge of this environmental issue. Several protocols for sampling microplastics in oceanic and coastal waters have been developed, compared and even harmonized for this purpose. However, these protocols may be not adapted for the study of estuarine environments, characterized by strong vertical, horizontal and temporal gradients.  In this work, microplastic sampling methods and strategies are discussed in relation to estuarine hydrodynamic processes. The analogies between the dynamical behaviour of microplastics and sediments make it possible to draw out recommendations for sampling microplastics based on several decades of research in estuarine hydro-sedimentary dynamics. In particular, we will discuss when, where, and how to sample microplastics in order to capture the most representative picture of microplastic pollution in these highly dynamic systems subject to strong anthropogenic pressures.  