bluuebunny/crossref_metadata_2025 huggingface dataset:
High-Resolution Spatiotemporal Monitoring Data During Groundwater Heat Pump System Operation
Authors: Baek Ji-Young , Oh Hae-Rim , Ha Seung-Wook , Lee Kang-Kun
Published: February 2023

Sustainability is one of the points in the design stage of the groundwater heat pump (GWHP) system. Thermal impacts on the surrounding environments should be accurately configured to ensure system sustainability. To achieve that goal, a sophisticated characterization of the target aquifer is required. So far, considering heterogeneity of subsurface environment in system design is challenging because there is lack of case studies provided high-resolution monitoring data enough to catch the heterogeneity. In this study, to detect the hydraulic and thermal responses to the GWHP operation, 12 monitoring wells were densely constructed between two geothermal wells at Eum-Seong, Republic of Korea. During the system operation, the high-resolution spatiotemporal changes in hydraulic pressure and temperature were detected by pressure sensors and fiber optic-distributed temperature sensing (FO-DTS). Monitored results were interpreted by time-series analysis to derive the thermal front velocity between monitoring wells. During the GWHP system operation, groundwater level monitoring results showed that a dynamic flow condition was generated especially near the geothermal wells up to 20 times of background flow. The estimated effective thermal velocities were comparable with the theoretically calculated velocities, but the higher velocity randomly appeared at the specific depths. From this case study, we confirmed FO-DTS was applicable to monitor the GWHP system. Those three-dimensional high-resolution monitoring data enabled to prove the existence of horizontal and vertical heterogeneity, indicating the need for accurate characterization of aquifer properties. AcknowledgementsThis work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2022R1A2C1006696). This work was also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (No. 2022R1A5A1085103). 
Modeling the effect of elevated CO2 on root exudation and ecosystem carbon storage in mature forests
Authors: Schufft Kristian , Fleischer Katrin , Rammig Anja , Yu Lin , Zaehle Sönke
Published: February 2023

Increased atmospheric carbon dioxide (CO2) is known to enhance  leaf-level photosynthesis. Following the carbon fertilization hypothesis, the increased photosynthetic assimilation may lead to an increase in plant biomass, therefore representing a negative feedback mechanism to rising CO2 emissions. The magnitude and limitations of this effect remain one of the major uncertainties in projecting the future influence of increasing atmospheric CO2 on terrestrial biogeochemical cycles and climate change.Forests contribute strongly to the contemporary terrestrial carbon (C) sink, however, the magnitude of the effect of elevated carbon dioxide (eCO2) on these ecosystems is still not fully understood. While experiments have demonstrated that young forests show increased aboveground biomass production under eCO2, the evidence for the effect on mature forests is still ambiguous. In these ecosystems, enhanced translocation of additional assimilated C belowground instead of investing in aboveground structure may significantly reduce C accumulation due to enhanced photosynthesis. One key mechanism in this process is exudation of C via roots into soil, which can increase nutrient availability to plants but also leads to soil C losses. By using a terrestrial biosphere model (QUINCY), which comprises a representation of the coupled carbon-nitrogen-phosphorus cycles in terrestrial ecosystems, we simulate the effect of elevated CO2 on exudation and its consequences for the C cycling and storage in mature forests. In comparison to other existing models we calculate exudation rates dynamic, based on plant carbon surplus and nutrient demand. We evaluate the effect using alternative representations of soil biogeochemical processes at the example of the EucFACE experiment in a mature Eucalyptus forest. We show that nutrient-stress induced increases in the exudation rate under eCO2 partially explains higher soil respiration and therefore lower C accumulation in this forest ecosystem.
Scalar turbulent flux observations in the entrainment layer and assessment of current parametrizations
Authors: Gibert Fabien , Edouart Dimitri , Monnier Paul , Collignan Julie , Lopez Julio , Cénac Claire
Published: February 2023

The entrainment zone (EZ) capping the convective boundary layer (CBL) is documented using lidar turbulent-scale observations. Sensible and latent heat fluxes have been measured during one hundred hours in CBL temperate and arid regions in free-cloud meteorological conditions. The EZ fluxes have been confronted with scalar gradients, integral scales of turbulence, wind shear, and surface sensible heat flux.  In agreement with former observations in stratified surface layer or with EZ large eddy-simulation (LES) studies, Lidar observations show that the buoyant oscillation period associated to the vertical velocity variance are found to be universal relevant parameters for EZ scalar fluxes and gradients. Attempts to introduce non-local CBL scales like the turbulent vertical velocity scale and height, the scalar interfacial layer jumps and the surface sensible heat flux globally increases the scatter of the data. Non-local parametrization particularly failed for EZ latent heat flux compared to sensible heat flux and for weak surface heat flux as it is usually the case in temperate region. Investigating a possible non-local parametrization of EZ vertical velocity variance, it was found that EZ wind shear and then EZ gradient Richardson number play a negligible role. Rather, observations often showed an excess of EZ vertical velocity variance with respect to CBL similarity law that may be explained by a significant contribution of wave-turbulence interaction in the entrainment layer.
First steps towards a data-driven groundwater vulnerability index for pesticides in Germany using probabilistic neural networks
Authors: Cooke Anne-Karin , Willkommen Sandra , Broda Stefan
Published: February 2023

The world largely relies on groundwater extraction for drinking water supply, which is also the case in Germany. In the EU, the Water Framework directive regulates the standards for a chemically good state of water bodies. Thresholds are often exceeded due to fertilizers and pesticides. Methods to assess groundwater vulnerability to contamination to chemical compounds are mainly index-based, GIS-overlay tools. Other approaches are process-based leaching models and statistical approaches. Commonly used index methods remain conceptual in nature and lack validation with monitoring data. Process-oriented approaches tend to focus on the soil layer. Statistical approaches remain underexplored. In the project FARM (Groundwater vulnerability assessment during authorisation procedure of pesticides), we aim to improve groundwater protection by developing a data-based vulnerability index that exploits the existing extensive data bases and covers all relevant environmental conditions and agricultural inputs.The federal groundwater quality monitoring infrastructure and of water suppliers delivered data of about 26.000 sites which are sampled for about 500 different pesticides. For pesticide monitoring data in Germany, such an exhaustive national database is unprecedented. Given this vast data set, this project aims to apply a fully data-driven approach to identify previously unknown, relevant factors and their interactions that drive groundwater vulnerability to pesticides. We aim to investigate the complex interactions between subsurface (soil, hydrogeology) and surface (meteorology, land use, crop sequences, agricultural practices) site characteristics with the physical-chemical properties (mobility, persistence) of pesticides. The potential of this data set will be exploited by the development, testing and validation of a supervised a machine-learning (ML) model. After an initial feature selection procedure, a Bayesian convolutional neural net will be trained on groundwater quality data and the mentioned extensive catalogue of features. This set-up takes the uncertainty into account introduced by the large percentage of left-censored data (concentrations below limit of quantification of the analytical method). High interpretability of the ML-model is essential, identified factors need to be comprehensible and actionable for decision-makers. We are dealing with a highly heterogeneous, asymmetric monitoring data set and strong biases in many variables are expected. This project thus pioneers in assessing the potential and suitability, as well as limitations and pitfalls of training neural nets on the status-quo of groundwater quality monitoring in Germany. A second major outcome of the project are specific recommendations on adjustments of the national monitoring (spectra of sampled substances, sampling frequency and timings, addition or reduction of monitoring wells in specific areas).
Flood and Wind-Induced Basic Service Disruptions across the Globe - A Modelling Approach
Authors: Mühlhofer Evelyn , Bresch David N. , Koks Elco E.
Published: February 2023

In the aftermath of extreme weather events, disruptions to basic services, such as access to healthcare, electricity, and mobility, may severely impact the functioning of society.  As both infrastructure investments and occurrence of extreme weather and climate events are at an all-time high, critical infrastructures are more exposed than ever to such adverse phenomena. While societal impacts of basic service disruptions can be substantial and widely felt, this aspect of risk is rarely captured in classic risk assessments. In this contribution, we are shedding light on this wider, socio-technical dimension of natural hazard-induced risks, in a globally consistent manner.For a selection of countries differing in size, world region, population density and income group, we compute spatially explicit patterns of basic service disruptions (access to power, healthcare, education, mobility and telecommunications) caused by historically observed tropical cyclone and flood events, and repeat the assessment with events commensurate with climate chance projections. To this end, we use the open-source risk assessment platform CLIMADA [1] and a bespoke network modelling approach relying on real-world infrastructure and population data [2]. We highlight geographic risk hotspots and demonstrate the importance of considering system interdependencies and cascading failures as opposed to static damage estimates to capture infrastructure risks from a human-centric perspective. Further, we study the influence of (country-specific) infrastructure network characteristics to develop heuristics (“rules of thumb”) of determinants which either perpetuate failure cascades or contribute to resilience.First results indicate, among others, that i) basic services which heavily rely on supporting infrastructure (such as healthcare and education access) are more likely to be disrupted, ii) floods cause different service disruption patterns than strong winds, iii) locations where service disruptions are experienced may diverge from locations with highest hazard intensities. [1] Aznar-Siguan, G. and D.N. Bresch (2019) CLIMADA v1: A Global Weather and Climate Risk Assessment Platform. Geoscientific Model Development 2 (7): 3085–9. https://doi.org/10.5194/gmd- 12-3085-2019 [2] Mühlhofer, E., E. E. Koks, C. M. Kropf, G.  Sansavini and D. N. Bresch. (in review). “A Generalized Natural Hazard Risk Modelling Framework for Infrastructure Failure Cascades.” https://doi.org/10.31223/X54M17 
Paleogeomorphic evolution in eastern North China controlled by the subsidence of the marginal sea shelf since late Cenozoic
Authors: Han Xu , Suo Yanhui , Li Sanzhong , Ding Xuesong , Song Shuangshuang , Tian Zihan , Fu Xinjian
Published: February 2023

Since the late Cenozoic, the geomorphology in the eastern part of North China have undergone tremendous changes under the influence of a variety of complex factors, but the exact process and finalization time are still controversial. The Badlands numerical simulation tool was used to dynamically reconstruct the geomorphic evolution process in eastern North China since the late Cenozoic (25 Ma). The  rationality of the simulation results was validated by comparing with  the regional tectonic framework and sedimentary distribution. The results show that the geomorphology in the eastern North China has been finalized and tends to evolve stably in Neogene, and is mainly controlled by tectonic activities. In addition, in the eastern part of North China during this period, there may be an ancient river - "East China River" around the Shandong Peninsula. It was formed no later than the Early Neogene, and may disappear during the Holocene. The results can provide quantitative basis for the study of geomorphic evolution and sedimentary process on the tectonic scale.
Where is the Eastern Alpine slab?
Authors: Plomerova Jaroslava , Zlebcikova Helena , Working Group AlpArray
Published: February 2023

First images of structure and dynamics of the Alpine orogeny came mostly from recordings of permanent observatories. Though density of permanent observatories has increased substantially since mid of the 20th century, yet it was not enough for detailed structural studies of the lithosphere-asthenosphere system in the complex Alpine-Mediterranean mountain belts. The tomographic images have changed especially during the last three decades, when several both small- and large-scale passive seismic experiments recorded huge amount of high-quality data at dense arrays, composed from both permanent and hundreds of temporarily installed stations. Thus the former monotonous eastward striking bend of the Alpine orogeny split into separated subductions with opposite polarity, one in the Western Alps and one in the Eastern Alps (Babuška et al., Tectonophysics 1990), later confirmed in more detailed tomography by Lippitsch et al. (2003), which included data from the TRANSALP experiment (TRANSALP Working Group, EOS 2001), the first research transect oriented on orogenic processes in the Eastern Alps. Data recorded during international AlpArray experiment, series of its complementary projects (e.g., EASI, SWATH-D, PACASE) as well as several other previous small-scale  experiments (e.g., ALPASS, BOHEMA, CIFALPS, CPB) allowed to unravel details of the Alpine structure and to search geodynamic models of the Alpine subductions. However, new questions arise with the new more precise images of the Alps. Following questions belong among them: 1) what is the origin of the E. Alpine subduction (Adriatic or European, or both); 2) if the E. Alpine slab is attached or detached, or, at which depth it resides; 3) how different methods, particularly crustal models incorporated into the body-wave tomography, disturb the real visualization of the E. Alpine slab. In this contribution we image the E. Alpine slab, evaluate effects of the crustal models on perturbations in the upper 100 km of the mantle and aim at answering the basic questions on the subduction beneath the Eastern Alps.
Rapid urbanisation and flash flood risk in desert regions: the example of Kuwait
Authors: Rözer Viktor , Alsahli Mohammad , Mehryar Sara
Published: February 2023

The discovery of oil in the middle of the 20th century has triggered an unprecedented economic boom and urban expansion in countries of the Gulf region such as Kuwait, Qatar, or the UAE. Kuwait’s population has increased 7-fold since the 1950s – mostly driven by immigration - creating the need for large scale housing and urban development projects. With a strong focus on the provision of housing and a car-centric planning approach the environmental consequences of these large developments were often not fully evaluated. In combination with changing rainfall patterns in the region as a result of climate change, severe flash floods have caused significant damage in recent years.Based on data from previous flash flood events and a high-resolution digital elevation model, a new flash flood susceptibility map for Kuwait has been developed. In combination with a detailed property level reconstruction of Kuwait’s urban expansion since the 1950s, we analyse how flash flood risk has developed in the Gulf state over time and which urban planning decisions have led to the recent jump in flash flood occurrences. Together with information about recent flash flood risk management plans, the study explores how Kuwait’s projected urban expansion until 2040 will contribute to its future flash flood risk.
Vision Transformers for building damage assessment after natural disasters
Authors: Lagrange Adrien , Dublé Nicolas , De Vieilleville François , Dupuis Aurore , May Stéphane , Walker-Deemin Aymeric
Published: February 2023

Damage assessment is a critical step in crisis management. It must be fast and accurate in order to organize and scale the emergency response in a manner adapted to the real needs on the ground. The speed requirements motivate an automation of the analysis, at least in support of the photo-interpretation. Deep Learning (DL) seems to be the most suitable methodology for this problem: on one hand for the speed in obtaining the answer, and on the other hand by the high performance of the results obtained by these methods in the extraction of information from images. Following previous studies to evaluate the potential contribution of DL methods for building damage assessment after a disaster, several conventional Deep Neural Network (DNN) and Transformers (TF) architectures were compared.Made available at the end of 2019, the xView2 database appears to be the most interesting database for this study. It gathers images of disasters between 2011 and 2018 with 6 types of disasters: earthquakes, tsunamis, floods, volcanic eruptions, fires and hurricanes. For each of these disasters, pre- and post-disaster images are available with a ground truth containing the building footprint as well as the evaluation of the type of damage divided into 4 classes (no damage, minor damage, major damage, destroyed) similar to those considered in the study.This study compares a wide range DNN architectures all based on an encoder-decoder structure. Two encoder families were implemented: EfficientNet (B0 to B7 configurations) and Swin TF (Tiny, Small, and Base configurations). Three adaptable decoders were implemented: UNet, DeepLabV3+, FPN. Finally, to benefit from both pre- and post-disaster images, the trained models were designed to proceed images with a Siamese approach: both images are processed independently by the encoder, and the extracted features are then concatenated by the decoder.Taking benefit of global information (such as the type of disaster for example) present in the image, the Swin TF, associated with FPN decoder, reaches the better performances than all other encoder-decoder architectures. The Shifted WINdows process enables the pipe to process large images in a reasonable time, comparable to the processing time of EfficientNet-based architectures. An interesting additional result is that the models trained during this study do not seem to benefit so much from extra-large configurations, and both small and tiny configurations reach the highest scores.
Identifying and Locating Volcanic Eruptions using Convolutional Neural Networks and Interpretability Techniques
Authors: Meuer Johannes , Timmreck Claudia , Fang Shih-Wei , Kadow Christopher
Published: February 2023

Accurately interpreting past climate variability can be a challenging task, particularly when it comes to distinguishing between forced and unforced changes. In the  case of large volcanic eruptions, ice core records are a very valuable tool but still often not sufficient to link reconstructed anomaly patterns to a volcanic eruption at all or to its geographical location. In this study, we developed a convolutional neural network (CNN) that is able to classify whether a volcanic eruption occurred and its location (northern hemisphere extratropical, southern hemisphere extratropical, or tropics) with an accuracy of 92%.To train the CNN, we used 100 member ensembles of the MPI-ESM-LR global climate model, generated using the easy volcanic aerosol (EVA) model, which provides the radiative forcing of idealized volcanic eruptions of different strengths and locations. The model considered global sea surface temperature and precipitation patterns 12 months after the eruption over a time period of 3 months.In addition to demonstrating the high accuracy of the CNN, we also applied layer-wise relevance propagation (LRP) to the model to understand its decision-making process and identify the input data that influenced its predictions. Our study demonstrates the potential of using CNNs and interpretability techniques for identifying and locating past volcanic eruptions as well as improving the accuracy and understanding of volcanic climate signals.
Impact of elevated Saharan Air layer on shallow marine convection
Authors: Gross Silke , Gutleben Manuel , Wirth Martin
Published: February 2023

Mineral dust is one of the major contributors to the global aerosol load with the Sahara being its largest source. Dust particles can be transported over many days and thousands of kilometers. The main transport route spans from Africa over the Atlantic Ocean towards the Caribbean. Most of the time dust-transport takes place in the so-called Saharan Air Layer (SAL).  During its transport the SAL affects the Earth’s atmosphere by scattering and absorption of solar and terrestrial radiation, and by changing cloud evolution and cloud properties. The main season for the transatlantic dust transport is during the boreal summer months. However, dust can be transported towards the Caribbean also during wintertime, although this happens with less frequency.Airborne lidar measurements with the combined water vapor differential absorption and high spectral resolution lidar system WALES provide simultaneous measurements of the water vapor mixing ratio and of aerosol properties. We use the measurements during the NARVAL-II experiment in August 2016 and during the EUREC4A experiment in January/February 2020 to characterize the long-range transported SAL in summer- and in wintertime, and to investigate its radiative effect and its impact on the subjacent shallow marine trade wind convection. We found, that a small amount of water vapor embedded in the SAL has a strong impact on the radiative heating effect of this layer and consequently also on the atmosphere’s stability. During summertime, when the SAL is well separated from the marine boundary layer, the radiative effect of the SAL dominates. The evolution of shallow marine clouds below the SAL is suppressed. In wintertime, the SAL is transported at lower altitudes and the dust layer is frequently mixed into the marine boundary layer. During this time of the year the effect of the SAL on the evolution and lifetime of marine trade wind convection is much more complex, as the dust particles within the SAL might additionally act as cloud or ice nuclei.In our presentation we will give an overview of the performed measurements and the radiative transfer calculations. We will present the radiative effects of the separated summertime SAL, and show first results of the impact of the wintertime SAL on the atmosphere’s stability and cloud properties.
What are the driving factors affecting urban groundwater quality? A multi-tracer approach for the assessment of Vienna’s shallow aquifers
Authors: Kaminsky Eva , Englisch Constanze , Griebler Christian , Steiner Cornelia , Götzl Gregor , Knoeller Kay , Sandén Hans , Laaha Gregor , Stumpp Christine
Published: February 2023

Urban shallow groundwater is highly impacted in terms of hydrogeology and water quality by anthropogenic activities and infrastructure, such as heating and cooling, surface sealing, leaking sewage pipes, and underground buildings. For a sustainable management of urban water resources, a better understanding of biogeochemical processes and its dynamics on a spatial and temporal scale in the urban subsurface is needed. So far, data sets including a critical minimum number of key parameters and an appropriate resolution in space and time have often been missing. Here, we introduce a multi-tracer approach applied to assess the shallow aquifers in Vienna. Water samples were collected twice, in autumn 2021 and spring 2022, respectively, from 150 groundwater wells in the city limits of Vienna. A comprehensive set of parameters (e.g. major ions, nutrients, heavy metals, water and nitrate stable isotopes) were analyzed to evaluate the spatial and seasonal variations in water origin and quality. Statistical analysis revealed that driving factors influencing groundwater quality include aquifer properties, interactions between groundwater-surface water, and redox conditions. A combined interpretation of conservative tracers indicated zones influenced by surface water - groundwater interactions that also influenced the water chemistry. Microbial anaerobic processes govern groundwater quality. In particular, contamination of nitrate from septic water and manure is locally reduced by denitrification, as proven by compound-specific isotope analysis, improving water quality. At the same time, other anaerobic processes, such as iron and manganese reduction, sulfate reduction, and methanogenesis deteriorate water quality. Finally, groundwater temperatures, up to 27°C, were observed close to urban underground infrastructure, hinting at subsurface buildings and surface sealing as stressors in shallow groundwater. In conclusion, our high resolution spatial sampling with the large set of parameters will not only allow a better understanding of groundwater quality dynamics, but also allows to evaluate effects to groundwater biodiversity and develop predictive mathematical models.
Exploration of the divergent effects of CMEs on low Earth orbiting satellites – current status of the project ESPRIT
Authors: Krauss Sandro , Kroisz Sofia , Drescher Lukas , Scherf Manuel , Lammer Helmut , Temmer Manuela , Strasser Andreas
Published: February 2023

With a view to the rising solar cycle 25 (maximum expected to be 2025/26) the solar activity level will steadily increase, which implies that the Earth’s atmosphere is expanding, and higher drag forces are acting on near-Earth satellites. To avoid earlier re-entries of satellite missions it is mandatory to monitor and at best accurately forecast extreme space weather conditions. We investigated different kinds of coronal mass ejections (CMEs) which had divergent effects on the trajectories of low Earth orbiting satellites. A special focus is given to the interaction of sequentially occurring CME events (e.g., 2021/11/03). So called multiple events lead to multiple field compressions and a capable to increase the severity of the impact on the near-Earth environment. 

Furthermore, we investigated the predominant chemical composition of Earth atmosphere based on satellite observation from the TIMED satellite (SEE, SABER). Additionally, we explored identified diverging behavior of various CMEs by simulating the events with the Kompot code, a 1D first-principles hydrodynamic upper atmosphere model. We found that for some of the selected events the atmospheric exobase and density profile shows some significant expansion mainly based on the increased XUV flux from the Sun. However, we also found that the sole effect of the incident XUV flux might only partially explain NO production, and the structure of the upper atmosphere. 
Reconstruction and risk predication of a typhoon-triggered debris flow via numerical simulation: A case study of Zhejiang Province, SE China
Authors: Wang Tengfei , Yin Kunlong , Li Yuanyao , Du Juan , Gui Lei , Guo Zizheng
Published: February 2023

Typhoon debris flows are recurrent phenomena with a high capacity to cause significant economic and life loss in the coastal areas. Accurately predicting the movement process and determining the potential zones and risk assessment are crucial to design mitigation strategies and to reduce societal and economic losses. In this study, the Wangzhuangwu (WZW) gully was chosen as the study object, which once broke out a debris flow induced by the Typhoon Likima on 10 August 2019. First, a detailed field investigation and interpretation of remote sensing imagery were carried out to study the trigger mechanism and quantify the characteristics of the debris flow. Second, the movement and deposition process of the 2019 WZW debris flow were reconstructed based on the Soil Conservation Service-curve number (SCS-CN) approach and a two-dimensional finite model (FLO-2D PRO model). The debris flow inundation and evolutionary trajectory were shown to be reasonably comparable with historical debris flows. Then, the potential hazard zones of debris flows with different recurrence intervals were determined based on the validated rheological parameters. Here we established a two-factors model that couples maximum flow depth with momentum to classify the hazard zones. Finally, we calculated the vulnerability distribution and economic risk of the buildings with different recurrence intervals based on a quantitative risk formula. This study provides a complete and efficient mean to determine the values of debris flow parameters and to implement a hazard and risk assessment based on numerical simulation. This proposed approach efficiently generated a debris flow risk distribution map that can be used for effective disaster prevention in the debris flow-prone areas.
Vesicle Morphologies of Popping Rocks: Implication for degassing processes during the 2018-2021 Mayotte submarine eruption
Authors: Verdurme Pauline , Chevrel Oryaëlle , Gurioli Lucia , Médard Etienne , Berthod Carole , Komorowski Jean-Christophe , Bachèrely Patrick
Published: February 2023

Between July 2018 and January 2021, the submarine eruption of Fani Maoré volcano, offshore Mayotte (Mozambique Channel), has been unprecedentedly well monitored with several oceanic cruises that provided a large number of samples (obtained by sea floor dredges) from the deep volcanic activity (3,300 m). The unique spatial and temporal sampling of the main edifice, flanks and distal ponded lava flows allows us to precisely track the vesicle morphologies and syn-eruptive degassing processes. This is an exceptional situation as deep-submarine eruptions remain poorly known due to the limited access to deep sites. We quantified textural parameters such as porosity, vesicle connectivity and vesicle size distributions (VSD) of these unusually gas-rich lavas, also known as popping rocks. Three different textures can be distinguished. The most vesicular (average of 35% vesicles) lava fragments display a unimodal distribution, and large vesicles are almost absent. Samples with intermediate porosities (average of 24% vesicles), show a bimodal distribution, with a dominant mode of large vesicles and a subordinate mode of small vesicles. Denser samples have the lowest porosity (average of 18% vesicles) characterized by a bimodal distribution, with a dominant mode of small vesicles. Samples with the highest and intermediate porosities were collected at lava flows emitted from the main eruptive vent during the early phase of the volcanic activity between July 2018 and August 2019. Both textures contain a population of small vesicles centred around the same mode suggesting a common origin, mostly related to the sudden gas-rich magma decompression. By contrast, the population of large vesicles is only present in pillow fragments located at the edge of the lava flows. These vesicles may be the result of bubble growth and coalescence during lava flow emplacement. Finally, the densest samples are only observed in lava flows that originated from a secondary fissure located on the Northwest, during the late phase of the volcanic activity between August 2019 and January 2021. This very poorly vesicular lava may result from a different magma batch (also supported by petrographic study) that was more degassed. Comparison with existing dataset from surface basaltic lava flows also revealed that most of our samples contain a significant amount of isolated vesicles (up to 18 vol%) emphasizing that popping rocks are able to retain gas at seafloor pressures. The detailed analysis of pillow lava texture allow us to make a clear distinction between lava flows erupted by Fani Maoré before and after August 2019. Our results also provide information on the eruption dynamics such as vesiculation processes and could be used to better constrain the rheology of the basanite melt for the Fani Maoré eruption.
Comparing lacustrine sedimentation rates and their response to climatic and environmental change
Authors: Zeeden Christian , Grandolas Luc , Vinnepand Mathias , Ulfers Arne , Sardar Abadi Mehrdad , Pierdominici Simona , Wonik Thomas
Published: February 2023

Continuous limnic archives may record millions of years of climatic and environmental change at their locality. Typically, such archives reflect environmental conditions in the lakes’ catchments, but also the imprint of large-scale atmospheric systems e.g. related to insolation and/or global ice-sheet dynamics. These parameters may vary considerably in space and time, and our understanding on patterns across continents that relate to this forcing is still incomplete. Comparing sedimentation rates from limnic archives covering fundamental changes in the Earth’s system like the Mid-Pleistocene Transition (change from 41 kyr to 100 kyr cycle world) has potential to shed light into spatial differences in Earth’s climate response, if applied carefully.In this context, we use age-depth models along with stratigraphic and chronological information e.g. from tephrochronology, magnetostratigraphy and tuning to assess differences in sedimentation rates of limnic geoarchives. We focus on limnic records that have been investigated during International Continental Scientific Drilling Program (ICDP) drilling projects, and specifically assess the influence of the Mid-Pleistocene Transition and the Mid-Brunhes Transition on sedimentation rates.
Natural and anthropogenic factors for activation of marine intrusion on the Bulgarian Black Sea coast
Authors: Nitcheva Olga , Vatralova Albena , Shopova Donka
Published: February 2023

Coping  with water deficit in coastal areas is a challenge when groundwater extraction must be relied upon. The problem is exacerbated when favourable conditions appear for activation of marine intrusion. Such could be significant pressure on groundwater bodies from water abstraction, which causes a change in the water level and, accordingly, a change in the direction of the groundwater flow. The present paper presents hydrological and water resource management analysis  of factors for activation of marine intrusion on the Bulgarian Black Sea coast using data from  monitoring observations of water quantity and quality  and hydrological model simulations. Anthropogenic impacts are analyzed using information about the actual structure and dynamics of the water supply.The results of the research show that in the Bulgarian Black Sea coastal zone the rainfalls in the past decade are below the country average. Hence marine intrusion processes are observed in the central and northern part of the region due to excess water intake from groundwater for domestic water supply. This imposes the necessity of searching alternative water sources from other territories and specific methods for water treatment.Key words: water deficit, groundwater water abstraction, marine intrusion, Bulgarian Black Sea coast
Antimony mobility and (bio)availability as reported from studies in derelict mines South Iberia
Authors: Higueras Pablo , Esbri Jose M , Battaglia-Brunet Fabienne , Peco Jesus D , Thouin Hugues , Barquero Jose I , Lorenzo Saturnino , Gloaguen Eric
Published: February 2023

Antimony (Sb) is a semimetallic element, with important applications in modern industry. Europe as a whole, and Spain, Portugal and France have been important suppliers of this element. However, nowadays European production is almost null, except as a by-product of lead mining, always containing variables amounts of Sb. Due to these considerations, Sb is considered as a critical resource for Europe.The ERA-MIN2 funded project AUREOLE (tArgeting eU cRitical mEtals (Sb, W) and predictibility of Sb-As-Hg envirOnmentaL issue) involves the French geological survey (BRGM), the Portuguese University of Porto, and the Spanish University of Castilla-La Mancha in the search of new criteria to prospect Sb mineralizations, as well as to assess the environmental possible consequences of the exploitation of Sb deposits.This communication summarizes the main results obtained through the last three years of research based on the assessment of environmental concerns of the element, based on the surveying of Sb derelict mineralizations in South-Central Spain. In these, geochemical and biogeochemical surveys have been carried out, aimed to identify the main factors affecting the mobility and (bio) availability of the element and related ones (mainly Pb, but also Hg) in the nearby physicochemical. The diversity and structure of bacterial communities on a former mining site was investigated. Biogeochemical interactions will be discussed in the different mine environments (tailings, dump, polluted soil, sediments).Geochemical and mineralogical soil characterization showed that most Sb remains as sulphide (≈99%), with a very small fraction bound to Fe and Mn oxy-hydroxides or organic matter, and a negligible proportions of leachable Sb. However, higher Sb mobility rates can be reached under oxidising conditions, with a long contact time between solids and water. The relationship between Sb concentrations in the soils and their measured enzymatic activity has yielded unclear results. Globally, results put forward that Sb mobility seems to be very low in semiarid climates, with also very low soil-to-plant transfer rates.
A Novel Approach to Constraining Carboniferous Tidal Currents using Bedforms in Tidal Rhythmites
Authors: Hewitt Jennifer , Baas Jaco , Bulawa Justyna , Ewing Amy , O'Connell Brennan , Green Mattias
Published: February 2023

A novel methodology shows that the dimensions of current ripples within tidal rhythmites can be used as a proxy for tidal current velocity, allowing us to contribute to the validation of numerical tidal model simulations. Our understanding of changing tides through geological history is facilitated by tidal simulations, which are generally poorly constrained due to the limited availability of proxy data. We aim to rectify this by developing a new type of geological proxy for tides based on sedimentary textures and structures, as bedforms are widely reported but uncommonly measured in the literature. The Carboniferous is a particularly data-rich time period with globally abundant tidal lithofacies including tidal rhythmites; successions of rhythmically alternating coarser and finer layers which can be used to describe tidal cyclicity, changes in the Earth – Moon system, and palaeoenvironmental conditions. Using data collected from a previously unstudied succession of Late Carboniferous (318 Ma) tidal rhythmites in Pembrokeshire, South Wales, UK, and empirical relationships identified through a series of flume studies in the literature, we deducted that the current ripples in our studied outcrop were formed at tidal flow velocities ranging between 0.28 and 0.34 m s-1. The latest palaeogeographical reconstructions depict South Wales as entirely continental, however the studied section revealed evidence of deposition in a shallow-marine palaeoenvironment. Identifying these palaeoenvironmental inaccuracies such as these allows us to rectify the palaeogeographical reconstructions; once tuned, the numerical tidal model simulation matched well with our proxy results. These promising findings demonstrate proof-of-concept of utilising bedforms as a proxy for palaeotides as well as its feasibility to validate tidal model simulations of other geological time periods and areas.  
How to consistently adapt soil parameters to express urban growth in physically based precipitation modeling ?
Authors: Leblois Etienne , Salas Aguilar Silvia-Patricia , Anquetin Sandrine , Gonzalez Sosa Enrique
Published: February 2023

Atmospheric limited-area models are superb tools built by atmospheric scientists, and can also be used by scientists from other disciplines. As hydrologists interested in urban rainfall hazard, we want to study possible changes in local-scale precipitation intensities and patterns under urban growth scenarios.Unfortunately, the parameterization of ground properties appears scattered in many datasets. These differ by their spatial resolution, computational type (exclusive categories expressed as integers, categories expressed as percentages in the patchwork/tile approach, continuous parameters as real numbers, month-dependent real numbers), and of course by their semantic (land use/land cover, radiative properties such as LAI according to one or another sensor, orography, soil type according to one or another research institute).From the above, the basic way to deal with expected land use changes in impact simulation changes would involve reading the scientific literature exhaustively - literally: to the point of exhaustion - to establish which parameter must be changed, and to hope that no inconsistencies will be introduced in the individual values or in their interdependence.We propose another, easier, and above all safer strategy. The first step is to recognize the "ground properties" are not a list of individual parameters, but a compound object where many parameters are related in a hierarchy of aspects  : parameters related to land use, parameters related to orography, etc. The determination of this hierarchy is quite easy using multivariate statistics, individuals being locations sampled in the domain of interest and data being the parameters values at these locations. This approach helps to establish the list of parameters connected to the intended change.Armed with this list, a "geographic cut-and-paste" strategy can be safely adopted to express intended land use change: the relevant parameter values of a representative (donor) location will be used at the target (modified) location, while leaving all other local parameters untouched.We illustrate this approach with the specific case of prescribing variable levels of urban development for the city of Querétaro, Mexico, in the technical context of using WRF's UEMS distribution (89 datasets distributed as 25633 files distributed in 219 directories).
Low-frequency standards for hydroacoustics in the Infra-AUV project
Authors: Malcher Freya , Ford Ben , Barham Richard , Çorakçi Can , Biber Alper , Robinson Stephen , Cheong Sei-Him , Ablitt Justin , Wang Lian
Published: February 2023

Low frequency Acoustics, Underwater Acoustics and Vibration (AUV) phenomena in water are used to detect major natural events such as earthquakes, tsunamis and volcanic activity, and are also used by the International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO) to check compliance with the treaty. Low frequency sound and vibration monitoring technologies are well established; however the lowest frequencies of interest are not sufficiently well covered by current measurement standards, limiting the reliability of data obtained. In addition, monitoring stations are also often located in extreme environments posing additional challenges for assuring the accuracy of measurements recorded by hydrophones. In this poster we describe the work that NPL, TUBITAK and ASN are doing in the Infra-AUV project to develop calibration methods for hydroacoustics in the frequency range from 0.5 Hz to 100 Hz.The project is establishing both primary standards (based on absolute realisations of the acoustic pascal), and secondary comparison methods to provide routes for effective dissemination and traceability. Two independent primary calibration methods are under development. The first uses a laser pistonphone (NPL and ASN) which uses optical interferometry to determine the motion (and therefore the generated pressure) of a piston driving a small chamber containing the hydrophone under test. The second is the coupler reciprocity method (TUBITAK and NPL) which allows hydrophones to be calibrated in more realistic ocean conditions (increased static pressure). Secondary calibration methods have been developed based on comparison of two devices in a small coupler (NPL and TUBITAK). The resulting calibration capability will underpin new measurement services and improve traceability in low frequency sound measurement and monitoring applications.
Identifying seismic fault geometry from focal mechanisms based on fault instability ratio during a stress inversion
Authors: Chang Chandong
Published: February 2023

Unveiling the geometry and kinematics of subsurface seismic faults is important for earthquake hazard assessment. Earthquake focal mechanisms can provide such fundamental aspects of faulting; however, they often require additional information to distinguish faults and auxiliary planes. We attempt to identify faults using a stress inversion technique, in which fault planes in individual focal mechanisms are selected based on the fault instability parameter. This stress inversion algorithm developed by Vavryčuk (2014) selects a higher instability nodal plane as the fault and finds 70-80% faults correctly to derive reliable stress results. Our tests using synthetic and simulated focal mechanism data with faults known beforehand show that faults are correctly identified especially when the instability of the selected fault plane is significantly higher than that of the auxiliary plane, which can be quantitatively expressed by the instability ratio of the fault plane to that of the auxiliary plane being higher than ~1.3. This constraint can improve further the ability to identify subsurface seismic faults. We apply this technique to the case of geothermal-induced earthquakes that occurred in Pohang, South Korea during 2016-2017. A total of 53 well-constrained and well-located focal mechanism data are inverted to derive a stress condition, during which faults are identified as higher instability nodal planes. These earthquakes occurred in spatially distinct portions of the region associated with water injection through two respective boreholes (PX-1 and PX-2). For the PX-2-related earthquakes, 70% of identified faults are well aligned in their locations and orientations with a large-scale fault, indicating that these earthquakes occurred on the patches of this fault. This fault is responsible for the 2017 Mw 5.5 main earthquake. Fault planes whose instability ratio is higher than ~1.3 are all consistent with this plane. There is more variation in identified fault orientations in PX-1 earthquakes. However, a few fault planes with high instability ratios are generally subparallel to one another. The locations and orientations of these high instability ratio planes are well aligned with a large-scale fault, which is different from, but subparallel to the PX-2 fault. This study demonstrates the possibility of identifying and imaging subsurface seismic faults only using faulting mechanics without other additional information.