bluuebunny/crossref_metadata_2025 huggingface dataset:
Equality of opportunities in geosciences: The EGU Awards Committee experience
Authors: Blunier Thomas
Published: February 2023

EGU, the European Geosciences Union, is Europe’s premier geosciences union, dedicated to the pursuit of excellence in the Earth, planetary, and space sciences for the benefit of humanity, worldwide. Every year, the EGU awards and medals programme recognises eminent scientists for their outstanding research contribution in the Earth, planetary and space sciences. In addition, it identifies the awardees as role models for the next generation of early career scientists to foster geoscience research.Nominations for all the medals and awards are submitted every year online by 15 June by the members of the EGU scientific community. Any person can be nominated except the EGU president, vice-president council members (not including ex- officio members) and chairs of the EGU committees. The EGU Council, the medal and award committees’ members and the Union and division officers are committed to soliciting nominations of deserving individuals by avoiding conflicts of interest. Each EGU medal or award is selected through a rigorous assessment of the candidates and their merits through the respective committee. The procedures for nomination, selection of candidates and the time schedule are described in detail on EGU websites.It is a strict necessity when recognizing scientific excellence by any scientific association providing equal opportunities and ensuring balance. The processes and procedures that lead to the recognition of excellence has to be transparent and free of gender biases. However, establishment of clear and transparent evaluation criteria and performance metrics in order to provide equal opportunities to researchers across gender, continents and ethnic groups can be challenging since the definition of scientific excellence is often elusive.This presentation aims to present the experience and the efforts of the European Geosciences Union to ensure equal opportunities. Data and statistics will be presented in the attempt to provide constructive indications to get to the target of giving equal opportunities to researchers across gender, continents and ethnic groups.
Improving stomatal optimization models for accurate prediction of photosynthesis under drought conditions.
Authors: Flo Victor , Joshi Jaideep , Sabot Manon , Sandoval David , Prentice Iain Colin
Published: February 2023

Accurate estimation of stomatal regulation is crucial for understanding how plants respond to changing environmental conditions, particularly under climate change. While stomatal optimization models have made significant progress in predicting instantaneous plants' carbon and water exchange, they often do not account for biochemical acclimation to drought over long time scales. In this study, we investigated the impact of incorporating photosynthetic acclimation on the accuracy of six stomatal optimization models in predicting carbon and water exchange in terrestrial C3 plants. By introducing the cost of maintaining a certain level of photosynthetic capacity into the stomatal optimization process, we incorporated photosynthetic acclimation to the previous seven days of environmental conditions. Using experimental data from 37 plant species, we found that accounting for photosynthetic acclimation improved the prediction of carbon assimilation in most of the tested models. Additionally, we found that non-stomatal mechanisms significantly contributed to photosynthesis limitation under drought conditions compared to well-watered conditions in all tested models. The hydraulic impairment functions of the stomatal models were unable to accurately account for drought effects on photosynthesis, indicating the need to consider photosynthetic acclimation to improve estimates of carbon assimilation under drought conditions.
Introducing a dynamic spatiotemporal rainfall generator for flood risk analysis
Authors: Khosh Bin Ghomash Shahin , Bachmann Daniel , Caviedes-Voullième Daniel , Hinz Christoph
Published: February 2023

Precipitation scenario analysis is a crucial step in flood risk assessment, in which storm events with different probabilities are defined and used as input for the hydrological/hydrodynamic calculations. Rainfall generators may serve as a basis for the precipitation analysis. With the increase in the use of high resolution spatially-explicit hydrological/hydrodynamic models in flood risk calculations, demand for synthetic gridded precipitation input is increasing. In this work, we present a dynamic spatiotemporal rainfall generator. The model is capable of generating catchment-scale rainfields containing moving storms, which enable physically-plausible and spatiotemporally coherent precipitation events. This is achieved by the tools event-based approach, where dynamic storms are identified as clusters of related data that occur at different locations in space and time, and are then used as basis for event regeneration. The implemented methodology, mainly inspired by Dierden et al. (2019), provides an improvement in the spatial coherence of precipitation extremes, which can in turn be beneficial in flood risk calculations.The model has been validated under different databases such as the radar-based RADALON dataset or spatially-interpolated historical raingauge timeseries of different catchments in Germany, which is also presented in this work. The validation indicates the models ability to adequately preserve observed storm statistics in the generated timeseries. The generator is developed as an extension to the state-of-the-science flood risk modelling tool ProMaIDes (Promaides 2023). The model also puts great focus on user accessibility with offering features such as an easy installation process, support for most operating systems, a user interface and an online user manual. Diederen, D., Liu, Y., 2020. Dynamic spatio-temporal generation of large-scale synthetic gridded precipitation: with improved spatial coherence of extremes. Stoch Environ Res Risk Assess 34, 1369–1383. https://doi.org/10.1007/s00477-019-01724-9ProMaIDes (2023): Protection Measures against Inundation Decision support. https://promaides.h2.de
Unravelling climate impacts of atmospheric internal gravity waves.
Authors: Šácha Petr
Published: February 2023

Unresolved processes in climate models present a major source of uncertainty in future climate projections.In this talk we will show the first results and introduce a newly founded five year project, which aims to re-examine the climate impacts of atmospheric internal gravity waves (GWs) using GW resolving simulations and to translate this knowledge to the development of modified GW parameterizations in climate models. Within the project, we will employ state-of-the-science high-resolution atmospheric datasets and theoretical methods for GW detection and wave-mean flow interaction to revisit and advance our understanding of GW effects on atmospheric dynamics, composition and coupling across atmospheric layers.GWs exist on a variety of scales, but typically a significant portion of the GW spectrum remains unresolved in global weather prediction or climate models and the GW impacts need to be parameterized. Our knowledge on GW impacts ranging from regionality of precipitation to the evolution of the ozone layer has been so-far based on their predominantly parameterized effects. Analyzing the resolved GW effects will improve our understanding on the forcing of selected atmospheric phenomena, but will also put additional constraints on the current GW parameterizations by showing to what extent their effects (and our current understanding) are artificial. This will help us to modify GW parameterization schemes with an ultimate goal of alleviating the uncertainty in future climate projections.
Slow slip events as stick-slip precursors in laboratory friction experiments on simulated fault gouges
Authors: Ikari Matt
Published: February 2023

Since the relatively recent discovery of slow slip events (SSEs), the nature of the relationship between SSEs and ordinary earthquakes has become one of the most important questions in earthquake science.  Specifically, questions as to whether SSEs decrease or increase the likelihood of large-magnitude earthquakes, whether or how slow and fast earthquakes can occur on the same fault patch, and whether SSEs are potential earthquake precursors have important implications for earthquake hazards.Here, laboratory friction experiments on simulated fault gouges are used to gain insight into the relationship between SSEs and ordinary earthquakes.  The experiments are conducted water-saturated, at room temperature and at low pressure (10 MPa effective normal stress) to simulate the shallow, near-surface portions of major fault zones.  A key feature of these experiments is employing driving velocities as low as 5 cm/yr (1.6 nm/s) to simulate natural far-field tectonic driving rates.  From a larger dataset which includes a wide range of simulated fault gouges, four gouge types exhibited consistent stick-slip and these are analyzed further.  These materials are pyrite, hematite, gypsum, and Carrara marble powders.Preliminary results show that the pyrite and hematite gouges exhibit small stress drops and increases in sample sliding velocity, interpreted to be SSEs, prior to stick-slips.  The SSEs occur near the peak in friction before the large stick-slip stress drop, suggesting that they are precursors.  In hematite at 5 cm/yr, the precursory SSEs exhibit stress drops on the order of 10’s of kPa and peak slip velocities within an order of magnitude of the driving rate, whereas the stick-slips exhibit stress drops of about 1 MPa and peak slip velocities of up to ~1 mm/s.  The peak stress at which the SSEs occur is within 1% of the peak stress prior to the stick-slip events.  Gypsum and Carrara marble, however, did not exhibit SSEs prior to stick-slips.  The results suggest that both slow and fast slip can occur on the same fault patch under the same conditions, and indicate the possibility that SSEs can be used as earthquake precursors in some cases.  However, the lack of precursory SSEs in the gypsum and marble gouges suggests that precursory SSE behavior is not universal and requires further investigation.
Glacier ice thickness estimation using deep-learning-driven emulation of Stokes
Authors: Cook Samuel , Jouvet Guillaume , Millan Romain , Rabatel Antoine
Published: February 2023

Mountain glaciers are a major source of sea-level rise and also represent an important freshwater resource in many mountainous regions. Thus, accurate estimations of their thickness and, therefore, the total ice volume are important both in predicting and mitigating the global and local effects of climate change. However, to date, only 2% of the world’s glaciers outside the ice sheets have any thickness data, due to the logistical difficulties of obtaining such measurements, creating a large and policy-relevant scientific gap.The recent development of a global-scale ice-velocity dataset, however, provides an ideal opportunity to fill this gap and determine ice thickness across the 98% of glaciers for which no thickness data is available. This can be done by inverting an ice-dynamics model to solve for the ice thickness. For accurate thickness results, this needs to be a full-Stokes model, but such a model is far too computationally cumbersome to apply on a global scale, and simpler, quicker methods usually based on the shallow ice approximation (SIA) are too inaccurate, particularly where sliding dominates glacier motion. The only attempt that has been made to leverage the global velocity dataset to retrieve ice thickness has, though, used the SIA, simply because higher-order approaches are not computationally realistic at this scale. Consequently, most of the widely-used global glacier models have made no concerted attempt to invert for global ice thickness, owing to these limitations.As an additional related problem, failing to fully assimilate ice-velocity data into an ice-flow model necessarily introduces a shock when initialising prognostic glacier simulations, resulting in model glaciers and predictions that may diverge substantially from their real-world counterparts.As a solution to these problems, we present results from a deep-learning-driven inversion model that emulates the performance of state-of-the-art full-Stokes models at a thousandth of the computational cost. This model, by solving an optimisation problem, can fully use and assimilate all available input datasets (surface velocity and topography, ice thickness, etc.) as components of its cost function to simultaneously invert for and optimise multiple control parameters (here, we focus on ice thickness). This approach also gives us the possibility of using the same ice-velocity field for inversion and forward modelling, reducing the magnitude of the shock inherent in traditional modelling approaches. With a view to a large-scale application to all the world’s 200,000 glaciers, we present initial thickness-inversion results for the relatively well-documented European Alps to help constrain model parameters and provide a test bed for extension to other glaciated regions, with initial extension to the Caucasus and the Southern Alps.
Retrieval of aerosol single scattering albedo over land using geostationary satellite data
Authors: Xue Yong , Jiang Xingxing
Published: February 2023

Absorbing aerosols from dust, industrial emissions and biomass combustion have a strong impact on solar radiation in the atmosphere, and they are considered to be an important source of regional air pollution[1], especially in East Asia, where the degree of variation of absorbable aerosols is very large, so it will have a significant impact on regional climate change. Aerosol single scattering albedo (SSA) is a key variable of aerosol absorption and a key metric of climate impact. Accurate estimation of SSA is crucial to reduce uncertainties in the study of atmospheric pollution and climate effects.The aerosol model of the current aerosol inversion algorithm is several typical regional aerosol candidate models obtained by cluster analysis of selected ground observation data[2]. These independent candidates' aerosol models result in the estimation of SSA being just a few simple constants, leading to a large bias in the results of SSA.In the current study, an atmospheric radiative transfer model parameterized by a two-stream approximation is used to construct a genetic algorithm for application to geostationary satellite Himawari-8 / AHI data to retrieve the aerosol SSA. The inversion process is constrained by AOD and the surface bidirectional reflectance distribution function (BRDF). Using this algorithm, hourly SSA data were retrieved was retrieved during day time.The algorithm was tested using the hourly L1 grid data of AHI from 00:00 to 07:00(UTC) from January to March 2020. Examples of the 10km satellite-retrieved SSA on March 15, 2020, are shown in Fig. 1. It can be seen that the SSA value in East China is significantly lower than in other regions. This may be due to the developed industries in southern cities that emit a large number of black carbon aerosols, while the temperature in winter is low, and the aerosol particles are not easily diffused, resulting in the SSA value of some areas maintaining a stable low value.To evaluate the retrieval SSA results, AERONET V3 datasets were used for validation. The AERONET datasets were selected in East Asia. Fig. 2 shows the scatter plots of AHI SSA retrievals versus AERONET at 470nm, (a) all AOD, and (b) only high aerosol loading (AOD>0.4 at 470nm), respectively. This indicates that the algorithm has great advantages for SSA inversion of heavy pollution conditions.The retrieval results from three months of AHI data were evaluated against the ground-based AERONET measurements. The AHI SSA shows good agreement with AERONET measurements, especially in heavy pollution conditions. This algorithm has been proven to be to characterize the temporal and spatial distribution of aerosol SSA.
Dynamic modelling of marine gas hydrates north of the South Shetland Islands (Antarctic Peninsula)
Authors: León Ricardo , García-Crespo Jesus , Urgeles Roger , Arasanz Raquel , García Xavier
Published: February 2023

In the Antarctic Peninsula, a marine gas hydrate system has been identified based on geophysical data (Lodolo et al., 1993; Tinivella et al., 2002). These data suggest gas hydrates average volume concentration of 6.0 ± 1.2% for in the accretionary wedge of the South Shetlands Islands (Tinivella, 2002).
Based on legacy seismic profiles (belonging to 17 oceanographic cruises) retrieved from the Antarctic Seismic Data Library System (SDLS), a continuous Bottom Simulating Reflector (BSR) has been mapped in the accretionary wedge, between Elephant and King George islands. This BSR is located at a sub-bottom depth between ca. 250 ms TWTT in the upper slope and ca. 1s TWTT at the base of the accretionary wedge.
The theoretical Base of Gas Hydrate Stability Zone (BGHSZ) calculated with a static model (León et al., 2009) for the present oceanographic conditions (pressure/bathymetry, seafloor temperature, geothermal gradient and salinity) is located 100 to 400 m shallower than this BSR level, considering available geothermal data for the area. The BSR-BGHSZ mismatch points that gas hydrates in the area seem to be in a transient state with respect to their theoretical location calculated from both pure methane and thermogenic compositions.
Dynamic models developed with TOUGH+HYDRATE in the frame of ICEFLAME project (PID2020-114856RB-I00, Spanish Ministry of Science and Innovation), reveal two possible scenarios for the above mismatch between BSR and BSGHZ: isostatic rebound and/or tectonic uplift.
References
León, R., Somoza, L., Giménez-Moreno, C.J., Dabrio, C.J., Ercilla, G., Praeg, D., Díaz-del-Río, V., Gómez-Delgado, M., 2009. A predictive numerical model for potential mapping of the gas hydrate stability zone in the Gulf of Cadiz. Mar. Pet. Geol. 26, 1564–1579. https://doi.org/10/czq8vq
Lodolo, E., Camerlenghi, A., Brancolini, G., 1993. A bottom simulating reflector on the South Shetland margin, Antarctic Peninsula. Antarct. Sci. 5. https://doi.org/10/bfcb22
Tinivella, U., 2002. The seismic response to overpressure versus gas hydrate and free gas concentration. J. Seism. Explor. 11, 283–305.
Tinivella, U., Accaino, F., Camerlenghi, A., 2002. Gas hydrate and free gas distribution from inversion of seismic data on the South Shetland margin (Antarctica). Mar. Geophys. Res. 23, 109–123. https://doi.org/10/fcgq3q
 
Concentrations of transparent exopolymer particles (TEPs) and their role in the carbon export in the South China Sea and western tropical North Pacific
Authors: Guo Shujin , Sun Xiaoxia
Published: February 2023

The role of TEPs in the carbon cycle remains inadequately understood in oligotrophic tropical oceans. This study investigates TEP concentrations, distributions, sinking behavior and fluxes in the oligotrophic South China Sea (SCS) and western tropical North Pacific (WTNP). The results suggested that TEPs levels were relatively low [< 60 μg Xeq. L-1 (μg xanthan gum equivalent per liter)] in both regions, and they were higher in the epipelagic layer than in deeper layers. TEP concentrations correlated significantly positively with Chl a and picophytoplankton biomass, and TEP-associated carbon contributed significantly to particulate organic carbon (POC) pool in the SCS and WTNP. The sinking flux of TEPs constituted a mean of 61% of the total POC flux in the SCS and 46% in the WTNP, highlighting their important role in carbon export in these areas. Generally, this study should provide good insight into the role TEPs play in the carbon cycle in oligotrophic tropical oceans.
Exploring the utility of global high-resolution NO2 columns from TROPOMI for investigating the diurnal variability and downscaling historical measurements
Authors: He Qin , Qin Kai , Cohen Jason Blake
Published: February 2023

Satellite remote sensing techniques can provide detailed information on the spatial and temporal distribution of nitrogen dioxide (NO2) in the troposphere, which enables us to monitor changes in NO2 levels over time and assess the effectiveness of emissions reduction measures. The TROPOspheric Monitoring Instrument (TROPOMI/Sentinel-5P) is particularly useful for identifying pollution sources within individual urban areas, as it has a higher spatial resolution with daily global coverage. In this study, we first compared the S5P-PAL reprocessing data with offline products (processor versions are earlier than v2.3.1) and used ground-based Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations in Xuzhou (a city in eastern China) to evaluate the performance. It was found that the size of the footprint can impact the validation results, and the smaller pixels (<29 km2) have a higher correlation with MAX-DOAS (R=0.91). Then we explored its serendipitous capability with the advantages of orbital characteristics and the high spatial resolution of the sensor. Using the overlapping orbits of TROPOMI at high latitudes, we applied a model-free inversion approach to derive diurnal NOx emissions. The orbits of Sentinel-5P allow for a greater than 20% probability of being observed twice within a 100-minute interval on the same day within a range from 35° to high latitudes.  Besides that, we proposed a downscaling method to generate high-resolution (0.05°) NO2 columns from the Ozone Monitoring Instrument (OMI/Aura) retrievals, which has provided continuous measurements since 2004 while having the limitation of relatively low spatial resolution. This model used data from the common observation period of TROPOMI and OMI after 2018 to derive the relationship between high- and low-resolution NO2 concentrations and applied to the historical dataset. Overall, this study demonstrates the utility of overlapping NO2 columns for investigating diurnal variability and highlights the importance of the spatial scale when analyzing and interpreting NO2 data.
Which N2O production processes are relevant when converting from grassland to cropland?
Authors: Buchen-Tschiskale Caroline , Lewicka-Szczebak Dominika , Nicolay Greta , Helfrich Mirjam , Flessa Heinz , Well Reinhard
Published: February 2023

During the last decades, large areas of grassland were converted to cropland across Europe, mainly due to the increasing demand of cropland following the expansion of biogas plant production (e.g. maize). However, the conversion to cropland bears a risk of nitrous oxide (N2O) emission due to enhanced nitrogen (N) mineralization. Until now, knowledge about N2O production pathways due to grassland conversion and in particular N2O reduction to N2 is very limited (Buchen et al., 2018), even though understanding of N2O processes and identification of sources are needed in order to devise mitigation options.N2O samples were collected periodically from manual chambers following chemical and mechanical conversion from permanent grassland to cropland (maize) at two sites with different texture (clayey loam and sandy loam) and fertilization regime (with and without mineral N-fertilization) in north-western Germany (Helfrich et al., 2020). Samples were analysed for natural abundance stable isotope signatures of soil-emitted N2O (δ15NbulkN2O, δ18ON2O and δ15NSPN2O = intramolecular distribution of 15N in the N2O molecule) by isotope ratio mass spectrometry (IRMS) and dual-isotope of N2O isotopic signatures (plotting δ15NSPN2O vs. δ18ON2O) were used for data evaluation (Lewicka-Szczebak et al., 2017). Although, isotopic signatures were very variable throughout the year at both sites, the clayey loam site exhibited a close correlation between δ15NspN2O and δ18ON2O suggesting that values were mainly controlled by N2O reduction to N2. At the sandy loam site this pattern was less pronounced, possibly because processes other than bacterial denitrification (e.g. fungal denitrification and nitrification) also significantly influence isotopocule values. Altogether, bacterial denitrification was found to be the most important process following grassland conversion to maize cropping.References:Buchen, C., Lewicka‐Szczebak, D., Flessa, H., Well, R., 2018. Estimating N2O processes during grassland renewal and grassland conversion to maize cropping using N2O isotopocules. Rapid Communications in Mass Spectrometry 32, 1053-1067.Helfrich, M., Nicolay, G., Well, R., Buchen-Tschiskale, C., Dechow, R., Fuß, R., Gensior, A., Paulsen, H., Berendonk, C., Flessa, H., 2020. Effect of chemical and mechanical grassland conversion to cropland on soil mineral N dynamics and N2O emission. Agriculture, Ecosystems & Environment 298, 106975.Lewicka-Szczebak, D., Augustin, J., Giesemann, A., Well, R., 2017. Quantifying N2O reduction to N2 based on N2O isotopocules – validation with independent methods (helium incubation and 15N gas flux method). Biogeosciences 14, 711-732.
Degradation behaviour of the Artificial sweetener-Acesulfame-K during riverbank infiltration system. A case study from Karany waterworks, Czech Republic.
Authors: Mursaikova Maria , Kuraz Michal , Hrkal Zbynek
Published: February 2023

Artificial sweeteners (ASs) are a class of low-level emerging organic contaminants (EOCs) that recently appeared in aquatic environment around the world due to its increased worldwide consumption. Once ingested by humans, the major amount of these artificial sweeteners excretes unchanged from the body and is transfered to the water environment through sewage systems. Consequently, artificial sweeteners are posing a new threat and a concern is growing over the contamination of a water environment.Due to its stability and mobility, ASs have long been considered as ideal tracers for a detection of domestic wastewater in natural water bodies, particularly groundwater. However, other previously conducted studies show that ASs are vulnarable to degradation under certain conditions. Therefore, fate, behavior, and ecotoxicological side of artificial sweeteners within waterbodies still remain ambiguous.Recently, ASs were also detected in the central part of the Czech Republic in the area of Káraný waterworks with a river bank filtration system. Considerable attention has been given to one of the widely used artificial sweetener - Acesulfame-K, which has been detected as a predominant contaminant in numerous pilot site across Europe and other worldwide countries.In our research we focus to pilot site of Jizera river, Czechia, where Acesulfame-K was detected in ranges 72.0 to 591.0 ng/l. Although the systems of riverbank filtration eliminate the presence of many anthropogenic contaminants in water, Acesulfame-K was still detected in groundwater with concentrations up to 75 ng/l.Based on available field and literature data, a two-dimensional large-scale hydraulic and transport model was developed using DRUtES software. For Acesulfame-K, the following first-order degradation rate was identified: λ = 0.0358 ± 0.0022 1/d. This result was further confirmed here by a small-scale laboratory experiment, where we mimicked conditions of our pilot site groundwater aquifer.
A multidisciplinary study of the “Bolle della Malvizza” mud volcanoes (southern Italy)
Authors: Fabozzi Carmela , Albanese Stefano , Ambrosino Maurizio , Ciarcia Sabatino , Cicchella Domenico , Natale Jacopo , Prinzi Ernesto Paolo , Verrilli Francesco , Vitale Stefano
Published: February 2023

We present a study on the mud volcanoes of Bolle della Malvizza located in the Irpinia sector of the southern Apennines (southern Italy). These structures are hosted in the Upper Cretaceous-Upper Miocene Fortore succession (Lagonegro-Molise Basin) and emit mud and bubbles of methane and CO2. Mud volcanoes are focused in a narrow area of ca. 5000 m2, consisting of eight main emission centres and several minor craters. We approached this research with a multidisciplinary study, including stratigraphic and structural surveys, geophysical and geochemical investigations and morphometric analyses. This study aims to investigate the origin of fluid migration and shed light on the pathways mainly controlled by faults.
The EuroMediterranean Submarine Landslide database: towards offshore geohazard quantitative assessement from submarine landslides and derived tsunamis
Authors: Urgeles Roger , Gamboa Davide , León Ricardo , Lovholt Finn , Vanneste Maarten , Cattaneo Antonio , Vila Carla
Published: February 2023

The Euro-Mediterranean Submarine landSlide (EMSS) database is a catalogue of submarine landslides of the Mediterranean Sea and the European continental margins of the Atlantic and Arctic Oceans. The catalogue is compiled from data available in the literature as well as information collected from geophysical data and so far not published in the scientific literature. A first version has been recently made available online (https://ls3gp.icm.csic.es/?page_id=553) and OGC services are being developed to be available soon through the EPOS data portal (https://www.ics-c.epos-eu.org/) in the frame of the EU funded project Geo-INQUIRE. Within Geo-INQUIRE we are currently working on a second version of the catalogue improving both areal coverage in the Atlantic Ocean and information relative to the source areas (as opposed to the previous version where only deposits and scars was considered). The aim of the latter improvement is to better characterize the failure and post-failure stages of submarine landslides. The new catalogue stores polygon and polyline geospatial features related to landslide deposits, landslide source areas and landslide scars as well as information relative to age, volume, area, runout, thickness, typology, scar elevation, relevant slopes and depths as well as related metadata. The catalogue includes submarine landslides that span from Miocene to Present day, although a clear bias exists towards submarine landslides of younger age, particularly for the smaller events. The reason for this is that the older and smaller events are difficult to identify on lower resolution geophysical data sets in deep-water and large sub-surface depths. The catalogue aims to offer improved understanding of mass-wasting processes, the potentially resulting tsunamis and derived geohazard. Recent case studies using a data subset (Gulf of Cadiz, SW Iberian Margin) portray the application of such type of databases in (probabilistic) analysis of submarine slope instability and tsunami-genesis from submarine landslides. We believe the current EMSS is the seed for the world ocean submarine landslide database. In this regard, we encourage the offshore geohazards community to contribute to enlarge the database. Shapefile templates will be made available to ease the task. This work is supported by the European Union’s Horizon Europe Research and Innovation Program under grant agreement No 101058518 (Geo-INQUIRE).
Soil susceptibility to wind erosion drives the abundance of microplastics in remote Scottish soils
Authors: Pavlíková Tereza , Pavlík David , Divíšek Jan , Nývlt Daniel
Published: February 2023

Microplastics have been found in various places, including not only densely populated areas of China or Germany but also remote high-altitude places like the Himalayas or the Pyrenees. However, the remoteness of a place is not determined only by its altitude. The Outer Hebrides (Scotland), with a low population and minimum industry, are remote in terms of direct pollution. This study aims to analyse the occurrence and spatial distribution of microplastics in soils of the Outer Hebrides to discover the factors driving the abundance of microplastics and to find how much more or less are remote Scottish soils polluted with microplastics than inland soils of populated areas.In the Isle of South Uist, 123 topsoil samples were collected along the western coastline and in four transects through the isle in the west-east direction. In total, 63 samples were analysed using an optical microscope to quantify the plastic microfibres visually using a semi-automatic algorithm. The amounts of microfibres were statistically processed, and their distribution was modelled for the entire archipelago.More microplastics are present in inland soils with loamy soil texture, denser vegetation and denser roots (median = 36,900 microfibres/L) than in coastal soils with sandy soil texture, sparse vegetation and low root density (median = 3,580 microfibres/L). Their abundance is mainly influenced by soil texture, vegetation density, and root density.With the south-western prevailing wind direction, we assume that most microfibres enter the island from the Atlantic Ocean, and the wind transports the microfibres inland to the east. Wind deflates the microfibres from coastal soils, and microfibres are deposited in inland soils. The inland soils are less susceptible to wind erosion, and the microfibres accumulate there.Thus, the remoteness of the Outer Hebrides does not guarantee low microplastic pollution. Contrarily, the Hebridean soils are extensively more polluted than most so far studied sites. The level of pollution is comparable to only a few studies where the abundance of microplastics in the soils is similar, e.g. Beijing (China), Lower Rhine basin (Germany) or Coimbra (Portugal). However, these sites are much more populated and interconnected, which suggests a great contribution of microplastic pollution from Atlantic Ocean and a great magnitude of wind transport processes in the Outer Hebrides.
An example of using open-source data and hydrology models for classroom exercises and term projects
Authors: Knoben Wouter , Spieler Diana
Published: February 2023

Recent developments in hydrologic science include a strong focus on open-source data sets and modeling tools. These developments can easily be leveraged into hydrologic education in the form of classroom exercises and term projects. Here we present a computational exercise designed to teach the concept of model structure uncertainty to students, using a specific selection of two catchments and two simple conceptual models from open-source data and tools. The exercise first familiarizes the students with the modeling tool they will use and then has them calibrate and evaluate model performance on each combination of model and catchment. For these specific catchment and models, model structure uncertainty is the dominant source of uncertainty (compared to data, parameter and objective function uncertainties). The exercise includes guiding questions that help the students reach the defined learning goals. Trials at the Technische Universität Dresden show that the exercises are effective in doing so. This introduction to open-source models and data yields the benefit of being easily expanded on during further exercises and term projects.
A Climatology of Dust Activity in the Atacama for 1950-202
Authors: Pinto Rovina , Fiedler Stephanie
Published: February 2023

Arid and semi-arid regions are sources of mineral-dust aerosols but very little is known of the dust activity in the hyper-arid Atacama Desert. The limited moisture supply and barren landscape should promote dust emission via wind erosion but the Atacama rarely sees strong dust outbreaks. Our study is the first detailed assessment of the observed dust reports for the Atacama. We analysed dust reports and meteorological data from surface synoptic observations spanning 72 years (1950-2021) to quantify the frequency distribution of dust events in the Atacama Desert, analyze changes over time, and evaluate influencing factors on dust events. Furthermore, we computed the threshold wind speeds for dust events at the different stations. A total of 1920 dusty days were recorded over a period of 72 years across the Atacama, where a dusty day is defined as a day with at least one recorded dust event. There is no perceptible trend visible but the results indicate several year-long periods with enhanced dust activity. Most dust events were observed in the 1990s with a rapid decline in dust activity post the early 2000s. Of the 1920 dust days, 72 days had a visibility of less than a kilometre, of which 12 days also reported dust storms. Chañaral was the dustiest station in the region with about 20 dust days per year. There is little seasonality in the dust activity, but a strong diurnal cycle with most dust events between 1500 and 1800 local time. Threshold wind speeds, t5, t25 and t50, are estimated as the minimum wind speed required for 5, 25 and 50% of the dust event frequency distribution. The thresholds allow us to determine the lowest winds capable of emitting dust from the surface and infer spatial differences in soil conditions due to soil moisture or land cover. Given the varying geomorphology of the surfaces in the Atacama, different threshold wind speeds are found at the stations in the Atacama. The t5 threshold wind speeds range from 6 ms-1to 14 ms-1across the desert. The evaluation of all stations yields annual mean threshold wind speeds of 10.9 ±1.6 ms-1, 13.2 ±1.9 ms-1and 15.6 ±2.3 ms-1for t5, t25 and t50. Ongoing research aims to evaluate the findings for the threshold wind speed against measurements from the pi-swerL Atacama Measurement EXperiment (LAMEX) conducted in October 2022.
The STIX imaging concept: model for data formation and image reconstruction methods for the Spectrometer/Telescope for Imaging X-rays on-board Solar Orbiter
Authors: Piana Michele , Massa Paolo , Volpara Anna , Massone Anna Maria , Benvenuto Federico , Perracchione Emma , Battaglia Andrea Francesco , Hurford Gordon , Krucker Sam
Published: February 2023

The Spectrometer/Telescope for Imaging X-rays (STIX) on-board Solar Orbiter measures the X-ray photons emitted by thermal and non-thermal electrons via bremsstrahlung mechanisms. STIX modulates the incident radiation by means of 30 sub-collimators that provide information on the complex values of specific Fourier components of the flaring X-ray source. This talk will illustrate this data formation process and explain how this model can be exploited to formulate image reconstruction methods including constrained maximum entropy, multi-scale CLEAN, feature augmentation, and Particle Swarm Optimization for parametric imaging. These methods will be applied against several experimental STIX observations and the reliability of the reconstructed morphologies will be validated by comparison with EUV maps recorded by the Atmospheric Imaging Assembly (AIA) on-board the Solar Dynamics Observatory.
Revisiting a short rotation coppice plot trial 10 years after biochar application: can we expect long-term effects on soil organic carbon content?
Authors: Pätzold Stefan , Bellantone Ester , Sandhage-Hofmann Alexandra , von Glisczynski Felix
Published: February 2023

Biochar and related commercial products have been intensively studied in the past years with respect to their potential benefit for soil fertility and carbon sequestration. Yet, little is known about long-term effects of modern biochar application to soil organic carbon (SOC) content at plot scale and in temperate climate.To evaluate potential effects of biochar application on soil organic carbon (SOC) and total nitrogen (Ntot) content, the soils of a field trial at Campus Klein-Altendorf, an experimental site of the University of Bonn (Germany), were re-sampled in 2022. The short rotation coppice plot experiment with four tree species had been established in 2012 on a Luvic Stagnosol formed from loess. Four treatments in threefold replication were realised: untreated control, compost, and two biochar–compost substrates with 15% (BCS15) and 30 % biochar (BCS30), respectively (in total 48 plots). All amendments were applied at 30 Mg dry matter ha–1 and incorporated to 0.15 m depth before the trees were planted.Prior to application of the amendments in 2012, the mean SOC and Ntot content were typical for arable loess soils in the region. In the first three years, no significant effects on soil fertility parameters and plant growth were observed, but C stocks were enhanced in the biochar treatments (von Glisczynski et al., 2016).During the re-sampling campaign after ten years, soil samples were taken from 0-0.1, and 0.1-0.2 m depth, corresponding to the sampling design at the beginning of the trial. The samples were conventionally analysed for SOC and Ntot (elemental analysis). Priority was given to the control and the 30% biochar treatment to estimate the maximum effects. The first and preliminary results point to a significant increase of the SOC content in the BCS30 treatment, but also in the untreated control when compared to the initial contents published by von Glisczynski et al. (2016). The mean SOC content in 0-0.2 m depth over all tree species raised from 12.5 g kg-1 to 13.8 g kg-1 (control) and 16.9 g kg-1 (BCS30) SOC, respectively. Total N also increased to 1.3 (control) and 1.4 g kg-1 (BCS30), respectively. Resolving more in detail the depth distribution clearly showed that the SOC increase occurred predominantly in the uppermost 0-0.1 m (BCS30: 21.5 g kg-1, control: 16.5 g kg-1); here, the BCS30 treatment showed a significantly larger C:N ratio than the control. In contrast, little difference was observed in 0.1-0.2 m depth (BCS30: 12.2 g kg-1, control: 11.2 g kg-1). The increase of SOC and Ntot also in the untreated control as well as their depth profiles point to an effect not only of biochar application, but also of abandonment of soil cultivation for 10 years in the short rotation coppice. However, further in-depth investigations are necessary to confirm these presumed long-term effects.
Predicting the global response of the glacier-fed streams and their bacterial microbiome to climate change
Authors: Bourquin Massimo , Peter Hannes , Robison Andrew Lean , Michoud Grégoire , Ezzat Leïla , Kohler Tyler J , Huss Matthias , Busi Susheel Bhanu , Fodelianakis Stilianos , Battin Tom J
Published: February 2023

 Glaciers are receding worldwide because of climate change, and as a consequence, glacier-fed streams are expected to undergo deep physical and chemical changes in the future, potentially inducing dramatic ecological shifts. At the base of glacier-fed stream ecosystems are bacteria, which, along with eukaryotic algae, form biofilms that drive biogeochemical transformations and fluxes of global relevance. Despite this importance, relatively little is known about the glacier-fed stream microbiome and even less on how it may be affected by climate change. The Vanishing Glaciers Project offers a novel and powerful opportunity to investigate this idea, with 16S rRNA amplicon data, shotgun metagenome sequencing, and physicochemical parameters assessed for glacier-fed streams distributed globally. Here, using data from 161 of the sampled streams, combined with glaciological modelling, we examined a) how the environmental template of these ecosystems will change according to several scenarios of climate change; b) how these changes will alter species distributions for the most prevalent bacterial community members; and c) how the ecological properties of abundant taxa vary along the gradient of glacier influence. We predict, that glacier-fed streams will undergo a process analogous to the “greening” of terrestrial alpine ecosystems, as benthic algal abundance is forecasted to significantly increase. Models based on 16s rRNA amplicon data predict the total bacterial abundance to greatly expand, but differences across taxa reveal unique responses to the modelled environmental changes. Corroborative evidence for shifts in bacterial communities along the gradient of glacier influence was found using metagenome assembled genomes, where we identified genomic features putatively adaptive to cryospheric conditions. Within these changes in taxa abundance, we highlight the shifting role of specialists within the community. Overall, this work sheds light on how bacteria adapt to the extreme environmental conditions of glacier-fed streams, and how climate change will impact these unique communities.
A bivariate rainfall frequency analysis framework in urban areas by coupling copula theory and stochastic storm transposition
Authors: Zhuang Qi , Liu Shuguang , Zhou Zhengzheng , Wright Daniel
Published: February 2023

Extreme rainfall is a critical “agent” driving flash floods in urban areas. In rainfall frequency analysis (RFA), however, storms are usually assumed to be uniform in space and fixed in time. Spatially and temporally uniform design storms and area reduction factors are oftentimes used in conjunction with RFA results in engineering practice for infrastructure design and planning. The consequences of such assumptions are poorly understood. This study examines how spatiotemporal rainfall heterogeneity impacts RFA, using a newly-introduced bivariate framework consisting of copula theory and stochastic storm transposition (SST). A large number of regionally-extreme storms with specific features—rainfall depth, duration, intensity, and level of intra-storm spatial organization—were collected. Rainfall intensity-duration-frequency (IDF) estimates exhibiting these bivariate features were then generated by synthesizing long records of rainfall via SST. The results show that dependencies exist among spatiotemporal storm characteristics. Bivariate frequency results exhibit smaller uncertainties but more complex physical meanings that the results from conventional methods. In particular, the highly spatially-organized storms play a leading role in frequency estimates.
crestr: An R package to perform probabilistic climate reconstructions from palaeoecological datasets
Authors: Chevalier Manuel , Chase Brian M.
Published: February 2023

Quantitative climate reconstructions are fundamental to better understanding past environmental changes and evaluating climate simulations. The proliferation of pollen-based reconstructions during the past decades has been instrumental in improving our understanding of past climate dynamics across various spatial and temporal scales. However, this knowledge has been mainly concentrated in North America and parts of Eurasia, and very few quantifications exist in the tropics. This global data imbalance is partly due to the sparser network of supporting pollen records in these regions and, in equal proportions, to the limitations of the most commonly used reconstruction techniques (e.g. the analogue technique or WA-PLS) in dealing with the specificities of tropical vegetation. To address this problem and produce the much-needed climate quantification from tropical regions, we propose using the probabilistic method CREST (Climate REconstruction SofTware) that uses probability density functions (‘pdfs’) fitted on modern occurrence plant data to reconstruct environmental parameters. CREST, which has been successfully employed in Africa and South America, offers many advantages over the classical approaches, including 1) a higher flexibility of application, 2) a better capacity to estimate uncertainties, and thanks to the recent developments of a dedicated R package crestr that includes a global calibration dataset, 3) CREST is applicable in every environment where plants currently grow. Considering these advantages, the large-scale application of CREST to quantitatively reconstruct important climate parameters from the existing tropical fossil pollen records should 1) help better integrate and interpret regional proxy compilations, 2) shed light on the spatiotemporal climate variability of tropical regions, and 3) determine the main modes of tropical climate variability. With this contribution, we will showcase the use of the crestr package with a novel temperature reconstruction derived from the 270,000-year-long, high-resolution pollen record from Laguna Fùquene in Colombia and discuss how this type of analysis could be generalised to determine spatial patterns of climate change from multi-record reconstructions