bluuebunny/crossref_metadata_2025 huggingface dataset:
Right for the wrong reasons? On hillslope sediment and the streampower model
Authors: Litwin David , Sklar Leonard , Malatesta Luca
Published: March 2024

The streampower law is widely used to model the detachment-limited endmember of bedrock channel evolution, in which rivers set their slope mainly to abrade or pluck material from the channel bed. The model suggests a strong sensitivity of river long profiles to tectonic forcing, local bedrock strength, and climate. This has made it a tool of choice for interpreting these signatures in landscapes, regardless of the applicability of detachment limited erosion. For instance, sediment flux can be a major control on channel slope, as channels steepen to evacuate sediment and maintain their bed elevation, which is neglected by the streampower law.While this is a well understood limitation, the implications become slightly murkier when the streampower law is used in 2D landscape evolution models that add a diffusion law to capture hillslope processes. We find that channel steepness increases with hillslope length, as channels have to steepen in order to erode the hillslope material added to the valley floor by diffusion processes. We show that this approximates some aspects of a transport-limited fluvial erosion model, but neglects others. Importantly, here channel steepening scales exactly with local hillslope properties, rather than those of the entire upstream watershed that would theoretically supply sediment. This has implications for interpretations of river profiles using chi-analysis and model inversion that rely on a version of the streampower law, especially when working between one-dimensional and two-dimensional approaches. We conclude with some extension of the physical significance of our findings, specifically related to constraints on the relationships between streampower erosivity, hillslope diffusivity, and grainsize.
Better mapping of groundwater-surface water exchanges over the Seine River catchment in a surface hydrological model
Authors: Hsu Shu-Chen , de Lavenne Alban , Andréassian Vazken , Rabah Amal , Ramos Maria-Helena
Published: March 2024

Surface hydrological models usually define their modelling units using topographic catchment  boundaries, which are then connected by the river network. Inter-catchment Groundwater Flows (IGFs) are water fluxes that do not respect these topographic boundaries. They can significantly influence river discharge. Therefore, surface hydrological models usually estimate IGFs indirectly, by adjusting the water balance across the topographic catchment. As they cannot be measured directly, the realism of these simulated fluxes can be questioned.Here, we investigate how a model calibration strategy could help to improve the physical realism of simulated IGFs. We propose a multi-objective calibration strategy, where we optimise the model simulation on two fluxes: river discharge and actual evapotranspiration using MODIS satellite estimates. Indeed, we hypothesize that better IGFs could be estimated if the water balance is more constrained by evaporation. We explore different objective functions to identify the most efficient way to use satellite data by looking at the model robustness in time and space.The Seine catchment is characterised by a complex, multi-layered aquifer system where the river loses water in some places and gains water in others. We evaluate the ability of the GRSD model, a semi-distributed hydrological model that implements the lumped GR5J in each subcatchment, to consistently describe this system thanks to this calibration strategy. The influence of four upstream dams is also considered in the modelling, as they have a significant impact on the hydrology. In particular, this work could help to understand the extent to which low flows are maintained naturally by groundwater or artificially by these dams.This work is partly funded by the ANR (CIPRHES project) and by the European Union’s HORIZON Research and Innovation Actions Programme under Grant Agreement No. 101059372 (STARS4Water project).
Studying gas flow on cometary surfaces with diffusivity variations using flow simulations and experiments
Authors: Zivithal Stephan , Kargl Günter , Macher Wolfgang , Güttler Carsten , Gundlach Bastian , Sierks Holger , Blum Jürgen
Published: March 2024

Comet surfaces have a complex morphology on large scales (such as pits, depressions, scarps and faults) as well as on small scales (such as particle size, porosity distribution and roughness of the comet surface). Little is known about the influence especially of small-scale structures on the gas-flow and the ability to lift off dust particles. Focusing on small-scale structures, we simulate diffusion processes applying Fick's law. For the upper and lower boundary of the simulated box, a flat sublimation front with constant pressure below the inactive surface layer and a perfect vacuum on the surface is assumed. By applying periodic boundary conditions in the planar direction, we mimic an infinite surface with periodic inhomogeneity. We performed the simulation with different variations of diffusivity. In one example, the simulation shows that a region of high porosity within a region of low porosity experiences an increase in the flow rate, as would be expected according to Fick's Law. Nevertheless, it also significantly changes the flow rate in the surrounding region due to lateral flows in the vicinity of the high diffusivity region. We analyze the results qualitatively and compare them with 3D Monte Carlo simulations in a similar setting, which shows a general agreement.In addition, we conduct experiments with a dedicated vacuum-chamber to measure the viscous permeability and Knudsen diffusion of granular materials by applying the binary friction model. The design allows measurements in different gas-flow regimes, with most samples mainly covering the free molecular flow and the transition region. In the last measurement campaign, bi-disperse samples of spherical particles were measured and the results show a good agreement with generalized models depending on the specific surface area of the sample. The current measurement campaign focuses on angular materials and the influence of shape properties on diffusivity. The results show that packings of highly porous hollow cylinders have a lower diffusivity than expected compared to more compact packings of spherical particles. A comparison with Monte Carlo simulations (from [1,2]) of packings of highly porous spherical particles also shows a higher diffusivity compared to the same measurements. Further measurements will show whether a dependence on a particular shape property could explain this discrepancy.[1] Macher, Wolfgang, et al. "Transmission probability of gas molecules through porous layers at Knudsen diffusion." Journal of Engineering Mathematics 144.1 (2024): 1-26.[2] Güttler, Carsten, et al. "Simulation and experiment of gas diffusion in a granular bed." Monthly Notices of the Royal Astronomical Society 524.4 (2023): 6114-6123.
Constraining explosive volcanic eruption parameters and environmental impacts using remote sensing observations of forest disturbance and recovery.
Authors: Udy Megan , Ebmeier Susanna , Watt Sebastian , Hooper Andy
Published: March 2024

Explosive volcanic eruptions can damage or destroy surrounding forests, with the potential to alter their characteristics over different timescales. The damage can range from minor/temporary damage to total destruction and burial of vegetated landscapes. While eruptions resulting in vegetation damage over 100s of kilometres are rare, some volcanoes regularly impact and damage local vegetation, with frequencies of months to decades. The intensity and mechanism of the driving volcanic process influences the extent and style of the forest damage, with resulting timescales and patterns of regrowth reflecting the nature of initial impacts and local floral, climatic and environmental parameters.As such, vegetation damage holds potential as a novel proxy for the magnitude and nature of volcanic eruptions. Particularly in the case of volcanic eruptions without recorded observations, vegetation damage could potentially constrain parameters such as tephra-fall deposit thickness, dispersal and pyroclastic density currents (PDC) distribution. Additionally, mapping the initial impact and trajectories of recovery are key to understanding the long-term environmental consequences of volcanic eruptions. Here, we aim to constrain eruption magnitudes and deposit volumes, particularly in remote environments, using optical (Landsat 8, Sentinel-2) and radar (Sentinel-1) satellite data to study forest disturbance and recovery following an explosive volcanic eruption in Southern Chile: the 2015 eruption of Calbuco volcano.The 2015 eruption of Calbuco consisted of three explosive episodes between the 22nd-23rd of April resulting in buoyant ash plumes depositing tephra over 100s km2, pyroclastic flows reaching over 6km and lahars reaching over 15km. Thus, different intensities and spatial extents of damage were experienced by the surrounding temperate broadleaf forests. We identify areas impacted by the different eruptive deposits using the disturbance and recovery signatures from the optical and radar satellite data. We observe a decrease in vegetation coverage and health immediately following the eruption in the areas impacted by PDCs, lahars and tephra. PDC impacted regions exhibit the greatest decrease in vegetation coverage and health, and consequently a much slower vegetation recovery rate. We develop a satellite-based methodology through time series analysis and cluster analysis to understand the impact of explosive volcanic eruption on vegetation properties. This allows us to assess the extent and severity of forest disturbance caused by the eruption and to map the rates of post-eruption vegetation recovery. We hope to expand this methodology to be applied to different ecosystems and for different styles of eruption using freely available satellite data. With the eventual aim of developing a toolkit for identifying the footprint of past volcanic eruptions on forest environments.
Large scale modeling of clay shrink-swell risk for current and future climate scenarios.
Authors: Boiselet Aurelien , Seiller Gregory
Published: March 2024

In recent years, the risk of clay shrinkage-swelling has emerged as a significant concern for land use planning and for insurance companies. These superficial clay soils exhibit vertical movement (contraction and expansion), linked to meteorological conditions. Despite the slow pace of these fluctuations, they can reach an amplitude large enough to damage buildings located on these soils. In France, this hazard appears in second rank in terms of losses with events that can generate more than one billion euros in losses .To better mitigate this risk, the French geological and mining risks office (BRGM) conducted a detailed mapping of exposure to clay shrink-swell across France. This departmental-scale analysis is based on the lithological nature of the soil, the mineralogical composition, geotechnical behavior, but also the loss experience observed. However, the susceptibility of a soil to swell has not been studied at global scale but rather over some territories. Given the current climate change, it is also necessary to understand the conditions linked to the occurrence of these events as well as the inherent impacts. This study focus on these two aspects: exposure and impact.To estimate whether a soil might be prone to swelling, we developed a machine learning model based on exposure maps published for France and the USA with a set of pedological parameters (CEC of clay, soil texture, bulk density, etc. coming from Soilgrids & Harmonized World Soil Database models) and geological parameters; associated with the presence of clayey soils with swelling capacity. We achieved a prediction accuracy of nearly 70% on our test set in these 2 countries. For France, this approach allows us to estimate that 52% of the territory presents a medium or high exposure to this peril, which is consistent with the BRGM analysis of 49%. With this approach we also estimated that 52% of Germany’s territory is exposed to medium to high swelling susceptibility.The impact analysis of this hazard is performed on France based on the publication of the CatNat decrees by the French Central Reinsurance fund, the loss ratio observed by AXA and climate indicators such as the Standardized Precipitation-Evapotranspiration Index (SPEI). The SPEI is a climatic indicator that is sensitive to water-balance variations, calculated over different time scales, allowing for the assessment of both short-term and long-term climatic conditions. The SPEI is particularly useful in regions where evapotranspiration plays a significant role in moisture availability. By analyzing the SPEI in conjunction with the CatNat decrees and the loss ratio observed by AXA, we can gain a comprehensive understanding of the current clay shrink-swell risk. This multi-faceted approach allows us to not only assess the current state of the hazard but also predict future trends.
Removing spacecraft-generated disturbances from the BepiColombo magnetic field data 
Authors: Constantinescu Dragos , Auster Uli , Heiner Daniel , Richter Ingo
Published: March 2024

In order to be useful for scientific analysis, the raw magnetic field data delivered by the BepiColombo Planetary Magnetometer must first be cleaned from stray magnetic fields originating from the spacecraft itself. This is especially important during the cruise phase, when the magnetic field instrument is still in the stowed position, close to various artificial magnetic field sources. The method we employ to remove these disturbances is a further development of the Maximum Variance Gradiometer technique already in use for cleaning the magnetic field data measured by the GeoKompsat-2A geostationary satellite. The main improvement over the above mentioned technique is the use of an intermediate non-orthogonal reference system which allows for decoupling of multiple disturbances. Here we describe the method and present the results of its application to the last Mercury flyby.
The use of radar information for improving the knowledge about landslides and floods events: an application to Calabria region (Italy)
Authors: Totaro Vincenzo , de Sario Simona , Chiaravalloti Francesco , Petrucci Olga
Published: March 2024

Floods and landslides are common natural phenomena that threaten society and ecosystems causing significant losses in term of human lives and financial damages. An in-depth investigation about the past occurrences of these events is of paramount importance for providing advances in the knowledge of natural and anthropogenic factors responsible for their generation. Considering rainfall as one of the key drivers for triggering physical mechanisms responsible for the occurrences of floods and landslides, a proper description of its characteristics needs to contemplate the intrinsic spatial and temporal variability. Despite the importance of such elements, rainfall monitoring often relies on sparse rain gauges, which lead to uncertainty in the identification of real rainfall patterns, making difficult to link precipitation records with observed damages. Meteorological radar represents a relevant tool for detecting rainfall spatiotemporal variability and providing ancillary information about the evolution of the events.Goal of the work is to develop a methodology that aims in reconcile records of landslides and floods events with the rainfall structures obtained by the joint use of data recorded by rain gauge network and radar data. The research has been carried out by moving from a consolidated catalogue of damaging events occurred in correspondence of floods and landslides in Calabria region (Italy) in 2019 and 2020. Rainfall was investigated integrating rain gauge data and maps of Surface Rainfall Intensity with resolution of 1x1 km2.Exploiting the availability of an accurate spatiotemporal reconstruction of precipitation structures, our investigation allowed to improve the specific knowledge about dynamics responsible of selected floods and landslides events. Preliminary results are supportive of the use of the proposed approach for integrating different sources of information in the assessment of the real dynamics of damaging events and for enhancing the use of their joint scientific content in the framework of risk assessment and mitigation.
Urgent Computing Integrated Services for Earthquakes 
Authors: Blanco-Prieto Rut , Monterrubio-Velasco Marisol , Pienkowska Marta , Ejarque Jorge , Bhihe Cedric , Zamora Natalia , de la Puente Josep
Published: March 2024

The Urgent Computing Integrated Services for Earthquakes (UCIS4EQ) introduces a fully automatic seismic workflow centered on rapidly delivering synthetic assessments of the impact of moderate to large earthquakes throughout physics-based forward simulations. This novel approach links High-Performance Computing (HPC), High-Performance Data Analytics (HPDA), and highly optimized numerical solvers. Its core objective lies in performing numerical simulations either during or right after an earthquake, accomplishing this task within a short timeframe, typically spanning from minutes to a few hours.During multi-node execution, PyCOMPSs orchestrates UCIS4EQ’s distributed tasks and improves its readiness level towards providing an operational service. UCIS4EQ coordinates the execution of multiple seismic sources to account for input and model uncertainties. Its comprehensive scope provides decision-makers with numerical insights into the potential outcomes of post-earthquake emergency scenarios.The UCIS4EQ workflow includes a fast inference service based on location-specific pre-trained machine learning models. Such learned models permit a swift analysis and estimation of the potential damage caused by an earthquake. Leveraging advanced AI capabilities endows our workflow with the  ability to rapidly estimate a seismic event's impact. Ultimately it provides valuable support for rapid decision-making during emergencies.Through the integration of high performance computational techniques and pioneering methodologies, our hope is to see UCIS4EQ emerge as a useful instrument to make agile and well-informed post-event decisions in the face of seismic events.With this study, we account for UCIS4EQ's continuous development through a number of case studies. These case studies will shed light on the most recent developments and applications of urgent computing seismic workflow, demonstrating its efficacy in providing rapid and precise insights into earthquake scenarios.
Monsoon Planet: Studying Monsoon Dynamics in an Idealized Setup
Authors: Katzenberger Anja , Petri Stefan , Feulner Georg , Levermann Anders
Published: March 2024

Monsoon systems transport water and energy across the globe, making them a central component of the global circulation system. Each monsoon system has its own regional characteristics ranging from particular continental shapes to dynamic vegetation patterns and the influence of mountain ranges. This individuality makes it difficult to access the common core meridional monsoon dynamics by only using observations or realistic simulations. Idealized frameworks have proven to be useful approaches to study monsoon systems with regard to their commonalties. Here, we present the latest insight of our work on the Monsoon Planet – an aquaplanet setup with an idealized circumglobal land stripe.
Examining Seismites using Anisotropy of magnetic susceptibility in and around the Kopili Fault Zone, Northeast India: A Characterization Study
Authors: md. Mujahed Baba , b.v. Lakshmi , v.m. Rokade , k. Deenadayalan , s.n. Patil , s. Priyeshu
Published: March 2024

 The North East Region (NER) of India is a Tectonically Active Zone with Noteworthy Intraplate Seismic Activity over the Past 200 Years. The tectonics and seismicity of large intraplate earthquakes in NER are poorly understood. As a result, the Kopili Fault (KF) has a complex tectonic setting with a history of past two large earthquakes of 1869 Cachar earthquake (Mw-7.4) and 1943 Hajoi earthquake (Mw-7.2) are being observed. Paleoseismological evidence reveals valuable insights into seismic hazard and the historical occurrence of earthquakes, as manifested in preserved liquefaction features. Field studies carried out by excavating trenches in five sites have uncovered secondary evidence of significant liquefaction-induced deformation features, known as seismites, occurring at a depth of approximately 2-3 meters below the surface. These features manifest as sand dykes and sills, exhibiting variations in colour, grain size, and sediment indurations across the sites. The findings from the excavated trenches have been summarized, incorporating multiple analyses to differentiate the seismites from depositional features. To aid in this distinction, the study utilized the Anisotropy of Magnetic Susceptibility (AMS) technique.The stereographic projection and bootstrap plots for the host sediment at the NB site clearly depict a vertical orientation for Kmin, while Kint and Kmax are distributed around the horizontal plane, indicative of sediment formation through fluvial activity. In the doublet liquefaction dykes NBRD and NBLD, all three axes exhibit random scattering. Notably, Kmin is sub-vertical, and Kmax is sub-horizontal in the southeast direction. The Degree of Anisotropy (Pj), Lineation (L), and Shape parameter (T) plots for the host specimen fall within the oblate field, whereas liquefaction dykes exhibit a distribution ranging from prolate to triaxial. In our presentation, we delve into a detailed discussion on how Anisotropy of Magnetic Susceptibility (AMS) serves as a valuable tool for comprehending seismite behavior and their occurrences, particularly in relation to large to great earthquakes.Understanding the tectonic and seismic characteristics of the Kopili Fault is crucial for assessing and managing earthquake risk in Northeastern India. Our studies will likely contribute to improved earthquake preparedness and resilience in the region for future prospecting.
The Hidden Potential of Gardens: Lidar-based Assessment of Urban Tree Benefits 
Authors: Wittemans Kelly , Dewaelheyns Valerie , Heremans Stien , Somers Ben
Published: March 2024

Gardens are companions of urbanization worldwide. Over 12% of Flanders' total surface area is garden, more than forests (10%) and nature reserves (2.9%). More than one third of urban areas worldwide exist out of garden. Despite their extensive area, gardens are often overlooked in research and their potential contribution to enhance living quality is un(der)explored. In our study, we delve into the potential of urban trees within gardens, examining their contribution within the broader framework of ‘OneHealth’.Trees offer diverse ecosystem services that play a crucial role in optimizing the health of people, animals, and ecosystems. These services encompass carbon storage and sequestration, mitigation of the urban heat island effect, reduction of stormwater runoff, provision of habitat, and various additional health benefits. The extent to which garden trees contribute to these services in comparison to other urban green spaces across different typologies is a critical question we aim to address.Light Detection and Ranging (LiDAR) data was used to create a canopy height model on which automated individual tree segmentation was performed. Tree height and crown width were derived directly from LiDAR data, while crown base height and diameter at breast height (DBH) were estimated based on empirical regression models. Tree genus allocation was based on a survey of garden professionals combined with garden inventories, which quantified tree genus abundance in Flemish gardens. Lastly, i-Tree ECO software was applied to calculate various ecosystem services. In the next steps of our research we will focus on quantifying the contribution of urban trees to landscape connectivity as well as to health benefits.Preliminary results already show a high potential of garden trees in certain urban areas. For the study area of Leuven, Belgium, garden trees are estimated to store 31.64 tonnes carbon (per ha), 0.20 ton carbon sequestration per year (per ha), 5.81 m3 avoided runoff per year (per ha). They can contribute between 11 and 33% of the total provided ecosystem services of urban trees. In areas characterized by open high-rise buildings and dense forest there is no contribution of garden trees. However, in areas with higher garden area, garden trees can contribute up to 81% of the total carbon storage, 65% of the total carbon sequestration and 86% of the overall reduction in runoff.
Can peatland restoration enhance drought and flood resilience in boreal forests?
Authors: Camiolo Sara , Teutschbein Claudia , Granath Gustaf , Grabs Thomas
Published: March 2024

Peatlands, unique wetlands where peat forms because waterlogging inhibits decomposing organisms, are predominantly found in the boreal region. In Sweden, nearly 18% of the land surface is covered by forested peatlands.  However, many of these areas have experienced severe anthropogenic disturbances in the 20th century. Drainage, a common practice to improve soil conditions for agriculture and forestry, along with commercial peat harvesting, has exerted considerable pressure on these ecosystems. In recent years, peatlands have been recognized for their value in climate-change mitigation, serving as crucial ecosystems that can store carbon and water. Peatland restoration, often referred to as rewetting, is considered an effective nature-based solution to reinstate hydrological, ecological, and biogeochemical conditions essential for various ecosystem services. Global and national policies actively promote peatland restoration, positioning it as a highly effective measure to build resilience against climate-change impacts. Following a series of extreme summers in Sweden, especially the mitigation of hydroclimatic extreme events, such as floods and droughts, is a widely claimed benefit. However, assessing the success of restoration efforts is difficult due to diverse hydroclimatic conditions, a wide range of catchment properties, long response times to restoration measures, and a limited number of long-term monitored restoration case studies. Specifically, restoration impacts on hydrological functioning, including water storage, flood control, groundwater recharge, and drought buffering, remain poorly understood. To strengthen the scientific basis and provide comprehensive insights for decision-makers, we conducted a literature review synthesizing existing empirical evidence on how rewetting boreal peatlands influences hydrological feedbacks. Our focus was particularly on the role of peatlands during drought and flood events, how their location and the time elapsed after restoration affects drought and flood vulnerability, and how peatlands themselves might be impacted by such extreme events. Our results represent a crucial initial step towards understanding the hydrological mechanisms regulating peatlands over time and under various hydroclimatic conditions, which is pivotal in guiding future conservation, rewetting and sustainable use of peatlands as nature-based solutions.
Monitoring of rainwater chemistry during the recent volcanic unrest at Vulcano Island (Italy)
Authors: Tripodi Francesco , Brugnone Filippo , D'Alessandro Walter , Bellomo Sergio , Brusca Lorenzo , Paonita Antonio , Calabrese Sergio
Published: March 2024

Volcanoes are an important source of gas and particles into the atmosphere, during the eruptive periods or even during passive degassing activity. The study of volcanic gases is a robust geochemical tool to understand, monitor and predict the behaviour of volcano activity, but it is also important to evaluate the effects of volcanic emission on a local and regional scale. The study of the chemistry of atmospheric deposition can provide important information in this regard. Vulcano Island is a stratovolcano located in the southernmost sector of the Aeolian archipelago (Sicily). Since the last eruption occurred in 1888-1890, volcanic emissions are characterized by intense fumarolic activity localized on the northeastern rim of La Fossa crater. Several episodes of volcanic unrest have occurred over the past 130 years, and the most recent period of crisis was between 2021 and 2022. It was characterised by the increasing fumarole temperatures and gas fluxes, shallow long-period seismicity, and diffuse soil degassing around the main crater. This study reports on the chemical composition of rainwater samples collected from November 2021 to January 2023, during the last unrest period of Vulcano Island. Fifteen rainwater samples were collected through a network of three bulk collectors; two of them were placed inside the fumarolic field, and the last one was located near Vulcano Porto. Rainwater samples were analysed for major and trace element contents, and physicochemical parameters were also measured. The pH of rainwater collected near the summit area reaches very low pH values (min 1.63), with a mean value of 2.29, which is significantly lower respect to the mean value at Vulcano Porto (5.7). The concentrations of dissolved solutes in rainfall (expressed as Total Dissolved Solids) are inversely proportional to pH and reach extremely high values in the most acidic samples (up to 1133 mg/L). The most influenced samples by the volcanic emissions are strongly enriched in sulphate, chlorine and fluorine as a direct result of the dissolution of acid gases in rainwater. In addition to the major species, high concentrations of potentially toxic trace elements (Al, As, B, Cd, Fe, Pb, Sb, Te, Ti, Tl, and REE) were found. At the most distal site (Vulcano Porto) the impact of volcanic emissions on rainfall is much less pronounced and the dominant source is mainly related to marine aerosol. These preliminary results on trace element concentrations in rainfall at Vulcano highlight the importance of these studies to fully evaluate the potential impact of volcanic emissions on rainwater and consequently on other environmental matrices (e.g. soils and plants), especially during a period of intense outgassing.
Drought intensity shapes legacy effects on grassland plant and soil microbial communities and their response to a subsequent drought
Authors: Oram Natalie J. , Praeg Nadine , Bardgett Richard D. , Brennan Fiona , Caruso Tancredi , Illmer Paul , Ingrisch Johannes , Bahn Michael
Published: March 2024

Drought has long-lasting legacy effects on grassland ecosystem functioning, which can manifest as shifts in soil microbial community structure and function and plant productivity that persist long after a drought passes. Increasing drought intensity causes abrupt shifts in plant productivity, plant-soil carbon and nitrogen dynamics, and soil microbial communities. However, very little is known about the role that drought intensity plays in the formation of drought legacies, and in plant and microbial responses to a subsequent drought. In a two-year experiment, we studied soil legacies associated with drought intensity in two model grassland plant communities with contrasting resource acquisition strategies (i.e., a fast- and a slow-strategy community). In the first year of the experiment, communities experienced a gradient of increasing drought intensity from well-watered to severely drought-stressed. In the second year, we determined soil microbial community composition and function, and plant community above-ground biomass in response to a subsequent drought. We found that the drought in the first year affected soil prokaryote and fungal community composition, microbial network structure, and soil function in the following growing season, and these effects were dependent on the past drought’s intensity. Soil drought legacy effects significantly altered plant community resilience to the subsequent drought: increasing intensity of the initial drought reduced plant community productivity resistance in slow-strategy plant communities, and decreased productivity overshoot seven weeks after re-wetting in fast-strategy plant communities. Our study shows that drought intensity causes distinct legacies in soil microbial community composition and function and alters the resilience of plant productivity to subsequent drought.
Deep learning and Process Understanding for Data-Driven Earth System Science
Authors: Reichstein Markus , Baghirov Zavud , Jung Martin , Kraft Basil
Published: March 2024

For a better understanding of the Earth system we need a stronger integration of observations and (mechanistic) models. Classical model-data integration approaches start with a model structure and try to estimate states or parameters via data assimilation and inverse modelling, respectively. Sometimes, several model structures are employed and evaluated, e.g. in Bayesian model averaging, but still parametric model structures are assumed. Recently, Reichstein et al. (2019) proposed a fusion of machine learning and mechanistic modelling approaches into so-called hybrid modelling. Ideally, this combines scientific consistency with the versatility of data driven approaches and is expected to allow for better predictions and better understanding of the system, e.g. by inferring unobserved variables. In this talk we will introduce this concept and illustrate its promise with examples on biosphere-atmosphere exchange, and carbon and water cycles from the ecosystem to the global scale.Reichstein, M., G. Camps-Valls, B. Stevens, M. Jung, J. Denzler, N. Carvalhais, and Prabhat. "Deep Learning and Process Understanding for Data-Driven Earth System Science." Nature 566, no. 7743 (2019): 195-204. https://doi.org/10.1038/s41586-019-0912-1.
Saltmarsh restoration through construction of sedimentation fields: controls on sediment delivery and hydrodynamics
Authors: Dale Jonathan , Ciappara Gabby , Farrell Michelle , Kennedy Michael , Ladd Cai
Published: March 2024

Saltmarshes provide important ecosystem services including habitat for wading and migratory birds, nursery grounds for commercial fish species, carbon storage, and flood defence through wave attenuation. Stimulating saltmarsh growth may improve the local level of flood protection, reducing the need for costly engineering works to sea walls and defences, whilst also enhancing the provision of other services. This is particularly important at locations where there is a need to restore and compensate for the loss of saltmarsh due to erosion caused by sea level rise, land claim, and a reduction in sediment supply.  One method of encouraging marsh growth is through the construction of sedimentation fields or polders, typically out of brushwood fencing, to reduce current velocities and wave heights with the aim of increasing sedimentation rates.  However, little is known of the impact polders have on the timing and rate of sediment delivery, or of saltmarsh response to changes in hydrodynamics. This is particularly the case for relatively exposed sites with a large tidal range, with most sedimentation fields constructed in sheltered locations with micro- to meso-tidal ranges such as the Wadden Sea.Here, we present results from a study of a macro-tidal sedimentation field at Rumney Great Wharf, Severn Estuary, Wales, which was constructed between 1999 and 2005. Field investigations, conducted during May to June and November to December 2023, involved the deployment of sediment traps and measurements of the current velocity and suspended sediment concentration to assess spatial and temporal variations in sediment delivery. Results indicate increased sediment availability in areas of lower elevation, with sediment trap data suggesting a difference of up to 3.7 g / cm2 / day due to elevation differences. Sediment cores were also collected and analysed from both inside and outside of the polders to assess the physical functioning of the marsh that has formed following polder construction.Findings provide insights into the suitability of sedimentation fields as a form of saltmarsh restoration and coastal flood defence, which are discussed in terms of mitigating against sea level rise and increased storm magnitude and frequency. This study also provides an evaluation of the potential for wider implementation of sedimentation fields as part of shoreline management strategies. It is recommended that further assessment is conducted to evaluate the influence of fence design, including length, height, and orientation, on site evolution to maximise provision of flood defence and wider ecosystem service delivery from these schemes.
Identifying opportunities and challenges of digitalization in agricultural water management in Austria
Authors: Thier Maximilian , Faller Christian , Brielmann Heike , Lindinger Helga , Stumpp Christine , Nolz Reinhard
Published: March 2024

Due to climatic changes and a predicted decline in arable land, a significant increase in water demand for irrigation is expected in Austria. To ensure water supply and food security while promoting the responsible use of available water resources, reliable data and forecasts are essential for decision-making in all areas of water management. Agricultural water management and irrigation practices require up-to-date data and reliable forecasts of water demand and availability for the planning and operation of irrigation systems. Decision-makers need the same information for water management planning, such as the assessment of the regional water availability, as a basis for the approval of irrigation projects. In Austria, a lot of data is collected regularly and is available in analogue or digital form. Digitalization offers the opportunity to collect, link, process and make this data available. As part of a study, funded by the Federal Ministry of Agriculture, Forestry, Regions and Water Management, digital data sources and digital tools relevant to irrigation in Austria were therefore collected, systematically compiled, and evaluated. The basis for the identification and selection was a comprehensive online and literature search. The systematic processing, compilation and evaluation constituted an iterative process in which representatives of the relevant stakeholder groups - water managers, farmers, and researchers - were involved through personal discussions and surveys to gain knowledge about awareness and use of digital tools. Deficits and potentials in connection with the digitalization of irrigation were also identified and discussed, and recommendations relevant to water management were derived. More than 70 digital tools and databases were identified and grouped according to their main characteristics, e.g. hydrology, climate, or soil, as well as according to subject areas based on the interests of the stakeholders. On this basis, information sheets were created to present the objectives that can be achieved with the application, such as promoting productivity or preventing the loss of irrigation water due to deep percolation. The results of this study provide information for a broad audience and identify knowledge and data gaps for future planning and research activities. However, to fully exploit the potential of digitalization in irrigation, efforts need to be made, for instance, to bridge the gap between digital technologies and the desired objectives, to promote inter-institutional cooperation and to improve both the quality and quantity of available data.
Aqueous alteration of primordial organic molecules: planetary implications
Authors: Lévêque Pauline , Bollengier Olivier , Le Menn Erwan , Bujoli Bruno , Queffelec Clémence , Afonso Carlos , Schmitz Isabelle , Marrocchi Yves , Champallier Rémi , Slodczyk Aneta , Sotin Christophe
Published: March 2024

Organic molecules are abundant in primitive solar system bodies such as comets and asteroids. These primordial organic compounds may have formed in the interstellar medium and in protoplanetary disks before being accreted and further transformed in the parent bodies of meteorites, icy moons, and dwarf planets. Primordial organics analogs were produced in a laboratory simulator of the protoplanetary disk. Their N/C ratio covers a wide range on either side of the solar composition. Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR MS) analysis of these analogs show that they are made of several thousands of molecules with masses between m/z 100 and 500.  The mass spectra show a gaussian shape with maxima around m/z 250. Highly condensed polyaromatic hydrocarbons (PAH) are the most common compounds identified in the samples with low nitrogen contents.Laboratory experiments have been carried out to investigate the chemical evolution of primordial organic analogs in contact with water. These organic compounds were placed in three different high-pressure devices covering a large domain of (pressure, temperature) conditions relevant to the interior of icy bodies. Each device provides complementary information on the evolution of the organic matter. The results are still being analyzed. Preliminary observations show that the organic matter is still composed of thousands of molecules in the mass range 100-500 m/z. Nitrogen poor organics seem relatively unaffected while nitrogen-rich organics are dramatically altered (heteroatoms released). The liquid phase becomes enriched in different ions likely to form salts. The remaining insoluble organic matter (IOM) is more aromatic than the initial one.As icy moons accreted and differentiated, the organic matter reacted with water. The residual IOM and the rocky minerals formed a refractory core. Our experiments suggest that the organic fraction of this refractory core is likely nitrogen poor and made of polycyclic aromatic hydrocarbons. These molecules further evolve as the refractory core heats up by the decay of the long-lived radioactive elements contained in the silicate fraction.
Open Polar: A Comprehensive Database for Advancing Arctic and Antarctic Research
Authors: Abu-Alam Tamer , Smart Katie A. , Aspaas Per Pippin , Longva Leif , Haugstvedt Noortje , Nilsen Karl Magnus
Published: March 2024

In the realm of environmental and climate science, addressing the multifaceted challenges our planet faces necessitates a comprehensive approach. Holistic solutions are crucially dependent on the integration and interoperability of data. The polar regions, especially the Arctic, are particularly vulnerable to climate changes, experiencing a rate of temperature increase that is four times faster than the global average [1]. Accelerated polar warming is frequently marked by sea ice loss, but also includes shrinking habitats for polar biospheres that in turn drastically affect Arctic peoples. Though enhanced at the poles, the effects of warming are wide-ranging across the oceans and continents of our planet, affecting weather patterns, ecosystems and human activities. Polar research is thus invaluable for researchers and policymakers and should be widely and freely available. However, In 2019 a significant findability gap was discovered for open access polar records, indicating the need for a cross-disciplinary research service to provide efficient and seamless access to open polar research [2].  
 The Open Polar database [3] was launched in cooperation between the University Library at UiT The Arctic University of Norway and the Norwegian Polar Institute in 2021. Open Polar promotes Findable and Accessible polar research, such that researchers, policymakers, and society have equal and unfettered access to polar region publications and data. Open Polar harvests metadata from over 4600 open access providers, filters for polar research using over 11000 keywords, and enriches the record result by defining geolocations and applying correct DOIs, before finally building the Open Polar database that is searchable by standard text or geolocation. Currently, the database includes nearly 2.5 million open access records, consisting of approximately 75% publications and 25% datasets. Nearly 2 years after its launch, Open Polar maintains a constant robust engagement, and we aim to improve our usage by incorporating new sources, reducing redundancies and considering integration with data archiving and open education services.  
 [1] Rantanen, M., Karpechko, A.Y., Lipponen, A. et al. (2022). The Arctic has warmed nearly four times faster than the globe since 1979. Commun Earth Environ 3, 168. https://doi.org/10.1038/s43247-022-00498-3 
 [2] Abu-Alam, T. S. (2019). Open Arctic Research Index: Final report and recommendations. Septentrio Reports, (3). https://doi.org/10.7557/7.4682 
 [3] https://openpolar.no/ 
Machine Learning Estimator for Ground-Shaking maps
Authors: Monterrubio-Velasco Marisol , Blanco Rut , Callaghan Scott , Bhihe Cedric , Pienkowska Marta , Ejarque Jorge , de la Puente Josep
Published: March 2024

The Machine Learning Estimator for Ground Shaking Maps (MLESmaps) harnesses the ground shaking inference capability of Machine Learning (ML) models trained on physics-informed earthquake simulations. It infers intensity measures, such as RotD50, seconds after a significant earthquake has occurred given its magnitude and location. Our methodology incorporates both offline and online phases in a comprehensive workflow. It begins with the generation of a synthetic training data set, progresses through the extraction of predictor characteristics, proceeds to the validation and learning stages, and yields a learned inference model. MLESmap results can complement empirical Ground Motion Models (GMMs), in particular in data-poor areas, to assess post-earthquake hazards rapidly and accurately, potentially improving disaster response in earthquake-prone regions. Learned models incorporate physical features such as directivity, topography, or resonance at a speed comparable to that of the empirical GMMs. In this work, we present an overview of the MLESmap methodology and its application to two distinct study areas: southern California and southern Iceland 
Source apportionment of sulfate aerosols over South Asia using δ34S
Authors: Clarke Sean , Holmstrand Henry , Budhavant Krishnakant , Remani Manoj , Gustafsson Örjan
Published: March 2024

Sulfate aerosols are short lived climate forcers that cool the climate, but at the cost of human health and the environment. Their short lifetime leads to an unequal global distribution, with massive emissions in South Asia, resulting in some of the highest atmospheric loadings. These emissions originate from natural and anthropogenic sources, with their relative contributions uncertain, due to emissions being short lived and diffuse. However, the stable isotopic composition (δ34S), holds some promise of improved apportionment of sulfate sources. The aim was to leverage this isotopic composition to distinguish sources of sulfate aerosols intercepted at the Maldives Climate Observatory Hanimaadhoo (MCOH). This site is strategically located to intercept a wide footprint of the outflow from South Asia.The results demonstrated that non-sea salt sulfate was largely of anthropogenic origin, contributing 93±21%, 85±14%, 61±20% in winter, spring, and summer, respectively. This study also found a moderate to strong correlation (r2 = 0.68) between continental anthropogenic (winter and spring) sulfate (δ34S) and fossil fuel black carbon (δ13C, Δ14C). This study provides improved constraints on sulfate sources in South Asia using stable δ34S isotopic analysis, which builds a foundation for future investigations aimed at unravelling the nexus of sulfate emissions in South Asia.