bluuebunny/crossref_metadata_2025 huggingface dataset:
Sea ice and ocean circulation changes during the last 140 kyr, offshore Adélie Land, East Antarctic continental margin, with special emphasis on last two deglaciations
Authors: Pesjak Lea , McMinn Andrew , Chase Zanna , Bostock Helen
Published: March 2024

Fuelled by anthropogenic warming, the duration of sea ice and ocean circulation near the East Antarctic continent at present-day, is changing and contributing to further ice sheet melt. Studying the functioning of these parameters, atmosphere, ocean, and sea ice, during past climate transitions (such as warming stages, i.e., deglaciations, and cooling stages, i.e., glaciations) may give us more understanding to the stability of the East Antarctic ice sheet in the future. Fossil diatom records found in deep ocean sediment cores can provide indications of past sea ice and surface temperature variability and can therefore deepen our understanding of future outcomes of present-day anthropogenic warming, including ocean circulation changes. However, very few sea ice and sea surface temperature reconstructions exist from past warming stages (deglacials) near the Antarctic continent. This is partly due to the fact fossil records are lacking from sediment archives retrieved from the Antarctic continental margin, possibly as a result of extended ice sheets and prolonged periods or permanent sea ice cover. In this study we analysed diatom assemblages (based on relative abundances of identified species and statistical analysis), the Eucampia index, Thalassiothrix antarctica, ice rafted debris (IRD), and the geochemical productivity indicators (biogenic silica and XRF derived Si/Al and Ba/Ti) in core TAN1302-44, collected from the slope offshore Adélie Land. The results show a pattern of glacial (cool periods) to interglacial (warm periods) sedimentary facies changes and include last two deglacials and the last glaciation stage. Two diatom assemblages coincide well with changes in glacial (low IRD, low productivity) to interglacial (high IRD, high productivity) facies. The persisting presence of Thalassiosira lentiginosa, representative of Assemblage 1, suggests the last glacial (MIS 4-2) is characterised by an open ocean environment with respect to sea ice. However, due to the increasing presence of Fragilariopsis obliquecostata, representing Assemblage 2, we conclude the last glacial also comprised a gradual build-up of sea ice, reaching a maximum duration at the end of MIS 2, before rapidly vanishing. Following the decrease in sea ice, based on the increased of Thalassiothrix antarctica within the deglaciation facies, we conclude Circumpolar Deep Water (CDW) influx increased over the slope. This observation occurs in both deglacials, one leading to MIS 5e, and other to Holocene interglacial. Finally, based on IRD rich interglacial facies, we conclude the CDW increase occurred prior to regional ice sheet retreat, leading into the Holocene. Together, these datasets suggest major sea ice, and oceanographic changes occurred prior to the last major ice sheet retreat, suggesting a progression of events may influence the demise of the East Antarctic ice sheet in the future.
Increasing stream water DOC concentrations in peat-affected catchments: insights from high-resolution water quality analysis
Authors: Houska Tobias , Müller Ingo , Kaiser Klaus , Knorr Klaus-Holger , Lau Maximilian , Jackisch Conrad , Kalbitz Karsten
Published: March 2024

Peatlands are an important natural terrestrial carbon sink. Any impact on the drivers of hydro-biogeochemical processes in these ecosystems can be particularly severe. Climate change and degradation by drainage and ditching are dramatically changing peatlands. Degraded peatlands turn from effective carbon sinks to emitters. They can also threaten drinking water supplies, as (heavy) metals can leach from degraded peatlands together with dissolved organic carbon (DOC). However, quantifying DOC fluxes from terrestrial to aquatic ecosystems is challenging. The hydro-biogeochemical processes at the soil-aquatic interface are not only complex but also occur at different spatial and temporal scales. These processes depend on a variety of constantly changing external conditions such as temperature, nutrient and oxygen availability. In addition, there is no sensor that can directly measure DOC concentrations in streams in situ.Here we investigated the DOC concentration in two nested catchments of two adjacent streams in the Ore Mountains of southern Saxony, Germany. One stream is dominated by mineral soils, the other by (degraded) peat soils. Each of the four sites is equipped with YSI-EXO fDOM sensors. Other data include discharge, water temperature, turbidity and electrical conductivity. A machine learning algorithm (Random Forest) was trained to predict DOC concentration from the available data set (validation r² between 0.85 and 0.98). The 15-minute resolution DOC data were analysed for potential driving factors. Interestingly, the area-specific loads of the peat-dominated catchment with 3.4 g C m-2 a-1 were not significantly different from those of the mineral soil-dominated catchment with 1.8 g C m-2 a-1. However, the annual loads were almost twice as high as previously determined from monthly data. With the high-resolution DOC data, we can identify periods of extreme DOC concentrations (up to 40 mg l-1) after heavy rain events in summer and constant high DOC concentrations of 20 mg l-1 during snowmelt in winter. By applying the algorithm to DOC:DON ratios, we were also able to quantify the different sources contributing to streamwater DOM with plant-derived material from peat and microbially-derived material from the mineral soil.Previous DOC measurements, mostly based on 2-week to monthly measurements, are likely to greatly underestimate the contribution of DOC to C fluxes in ecosystems. This is particularly important for C-rich ecosystems such as peatlands.
Tracking three-dimensional growth of magma-filled fractures by joint inversion of high-resolution geodetic and seismicity data
Authors: Gonzalez Pablo J. , Jiang Yu , Charco Maria , Sansoti Eugenio , Reale Diego
Published: March 2024

Magma-filled fracture propagation is the primary magma transport mechanism near the surface at ocean island basaltic volcanoes. Therefore, developing and implementing efficient workflows to track magmatic intrusions in the elastic-part of the oceanic lithosphere (
The differences of seasonal and inter-annual variations  between soil heterotrophic respiration and autotrophic respiration in the subtropical forests of China
Authors: Yan Yibo , Wang Xiujun , Wohlfahrt Georg
Published: March 2024

There is evidence of large differences in the spatial and temporal variations between soil heterotrophic respiration and autotrophic respiration in terrestrial ecosystems. This study was designed to test the hypothesis that there were differences in the seasonal and inter-annual variations between heterotrophic respiration and autotrophic respiration in subtropical forestlands. Here, we applied calibrated heterotrophic respiration and autotrophic respiration models to estimate soil respiration over 2002-2022 at three forest sites in subtropical China. Our results showed smaller seasonality and inter-annual variability in heterotrophic respiration than in autotrophic respiration. The inter-annual variation was strongest in winter for both heterotrophic respiration and autotrophic respiration. The main driving factor responsible for temporal variations was soil temperature for heterotrophic respiration, but fine root biomass for autotrophic respiration. There was a significant increasing trend only in autotrophic respiration over 2002-2022, which corresponded to the significant increasing trend in fine root biomass. Divergent inter-annual changes in these two respiration components led to the significant increasing trend in autotrophic respiration’ contribution, as well as total soil respiration. Due to the decreasing seasonality of soil temperature and fine root biomass, there was a declining seasonality in both heterotrophic respiration and autotrophic respiration. Our results highlight the importance of separately modeling and estimating soil heterotrophic respiration and autotrophic respiration in subtropical forestlands.
Follow-up at the small scale during snow deformation. Microstructure evolution and local heterogeneities at various strain-rates.
Authors: Georges David , Védrine Louis , Bernard Antoine , Bonnetier Mathilde , Montagnat Maurine , Hagenmuller Pascal , Chambon Guillaume
Published: March 2024

Snow deforms naturally in a large range of strain rates covering ductile to brittle regimes. In all situations, snow deformation is characterized by complex mechanisms taking place at the microstructure scale, with interplay between metamorphism, sintering and grain rearrangements. Current modeling efforts require better understanding and formulation of the microstructure-scale complexity.We performed compression experiments on snow samples in order to follow the microstructure evolution at various imposed displacement velocities. The resulting strain-rates varied between 10-2 s-1 and 10-7 s-1. Samples (15 mm height, 15 mm diameter) were made out of rounded grains with an initial density of about 250 kg m-3. Samples evolution was followed by means of micro-computed X-Ray tomography (microCT) with full 3D scans performed during the slower tests and simple radiographies at a high frequency for faster tests.In this presentation we will focus on the various metrics used to analyse the microstructure evolution on one side, in particular specific surface area (SSA) and the minimum cut area. On the other side, we will present recent developments based on digital image and volume correlations (DIC and DVC) performed on the radiographies and the 3D microCT images with the open access SPAM software (https://hal.univ-grenoble-alpes.fr/hal-03020460), in order to follow the local strain field.We will provide analyses of the interplay between metamorphism and strain in the microstructure evolution and of the impact of mechanisms at bonds in the various strain-rate regimes explored (ductile to brittle). Snow deformation localisations revealed by DIC and DVC observations will be presented. They can be inherited from initial sample heterogeneities or take the shape of compaction bands, depending on the strain rate.All these data and analyses will be further interpreted regarding the understanding of the small scale mechanisms of metamorphism and deformation of snow and their modeling frame.
Unraveling the dynamics of the 2021 Arkalochori foreshock swarm: a fusion of machine-learning models and non-extensive statistical physics
Authors: Vallianatos Filippos , Kapetanidis Vasilis , Karakonstantis Andreas , Michas Georgios
Published: March 2024

On 27 September 2021, a significant Mw=6.0 earthquake struck near Arkalochori village in central Crete, Greece, about ~25 km south-southeast of Heraklion city. Remarkably, an extensive seismic swarm lasting nearly four months preceded the mainshock, activating structures near its hypocenter. In this work, we investigate the foreshock swarm by leveraging waveform data from seismological stations of the Hellenic Unified Seismic Network (HUSN) that were operational on Crete Island during its occurrence. Our approach involves the utilization of the EQ-Transformer machine-learning model, pre-trained with a diverse dataset comprising ~50,000 earthquakes sourced from the INGV bulletin (INSTANCE dataset). We employ a sophisticated methodology that incorporates a Bayesian Gaussian Mixture Model (GaMMA) to associate automatically picked P- and S-wave arrival times with event origins. Subsequently, the events are located using a local velocity model. Our findings reveal the detection and precise location (ERH < 1 km, RMS < 0.2 s) of over 3,400 events in the activated area between late May and 26 September 2021, showcasing a substantial increase compared to existing catalogs derived from routine analysis using conventional methods. The spatiotemporal distribution of the foreshock seismicity is examined to unveil migration patterns, potentially linked to fluid dynamics and pore-pressure diffusion. Furthermore, we explore the evolution of seismicity concerning different structures activated during the seismic swarm, with a particular focus on the final days leading up to the mainshock. Finally, our results are subjected to analysis through non-extensive statistical physics methods, providing a comprehensive understanding of the complex dynamics culminating in the Arkalochori earthquake sequence.AcknowledgementsWe would like to thank the personnel of the institutions participating to the Hellenic Unified Seismological Network (http://eida.gein.noa.gr/) for the installation, operation and management of the seismological stations used in this work. The present study is co-funded by the Special Account for Research Grants (S.A.R.G.) of the National and Kapodistrian University of Athens.
Plant diversity-climate interactions from a modeling perspective
Authors: Hu Pin-hsin , Reick Christian H. , Kleidon Axel , Claussen Martin
Published: March 2024

Mounting evidence from field observations has shown that high functional diversity is associated with strong ecosystem resilience and stability. However, plant ecology studies have focused on the passive response of global ecosystems to climatic changes while the impacts of plant-functional diversity on climate including its feedback are seldom addressed. Moreover, state-of-the-art climate models are insufficient to address such topics. Their land component models cover only a restricted range of present-day plant features, so that adaptation at the sub-grid scale is ignored. Based on a process-based plant functional trade-off scheme developed by Kleidon and Mooney (2000), we have set up a new vegetation model JeDi-BACH into the land component of the ICON-Earth System Model (ICON-ESM). The advantage of this new model is that the representation of global vegetation is an emergent outcome of environmental filtering following several well-known fundamental functional trade-offs that link plant functions to abiotic and biotic attributes. In such a way, plants dynamically adjust to the changing environment and meanwhile modify climate. With this new model, we present a series of sensitivity studies investigating the effect of plant trait diversity on the coupled vegetation-climate system in a coupled land-atmosphere setup. We found that high plant diversity ecosystems tend to stabilize terrestrial climate in a high water-turnover state, leading to a wet and cool climate. The enhancement in evapotranspiration with increasing diversity found in our study is consistent with the BEF (Biodiversity-Ecosystem Functioning) relationship derived from the field studies. Our modeling results demonstrate the importance of the "biodiversity-climate feedback" and highlight the role of plant functional diversity in shaping a robust climate.Kleidon, A. and Mooney, H. A.: A global distribution of biodiversity inferred from climatic constraints: Results from a process-based modelling study, Glob. Chang. Biol., 6(5), 507–523, doi:10.1046/j.1365-2486.2000.00332.x, 2000. 
Decision systems for nature based solutions to mitigate floods
Authors: Bostenaru Dan Maria
Published: March 2024

In the 20th century often the solution to mitigate floods was putting a corset of reinforced concrete to rivers. An example is one of the case studies in our project which we will detail, the Vidraru dam on Arges river, where a neighbourhood was built after the 1940 floods. In the 21st century however the approach is different. Several years ago a communication session was dedicated to achieving more flood resilience through floodplains on the Danube, and also several years ago a doctorate was concluded on landscape architecture solutions to mitigate floods on the Rhine. The geographic areas are different, and so are the localities and the early 20th century constructions which might be affected by floods and their relationship to the city - ex. peripheral Siedlung in Germany. Today one can look more systematically. A recent course of the European Commission offered insights to natural disaster mitigation through nature based solutions across the globe. We also reviewed literature in a nice part of this: decision systems to prioritise interventions based on cost-benefit to mitigate floods. On this basis, identifying gaps - the papers cover some of the aspects of this issue at once, not all of them - we elaborated a decision tree and its taxonomy according to criteria related to the building and the river landscape. The indices to quantify these criteria will be shown. This will be exemplified in case studies comprising Bucharest, Rome and Lisbon. It can be converted into an ontology for software planning, as in numerous European projects related to protection of architectural and archaeological heritage protected from climate change with IT support which go even further, towards Internet of Things. The context of future possible projects will be shown in the discussion.
Impact of Halting Dam Operations on Downstream Flow: A Modern Modelling Approach
Authors: Sadeqi Amin , Kasvi Elina , Marttila Hannu , Alho Petteri
Published: March 2024

Europe confronts a critical environmental challenge, with only one-third of its rivers meeting the “good ecological status” criteria of the EU Water Framework Directive as many river systems are impacted by damming and regulation. Our research focuses on the Myllykoski hydropower dam on Kuusinkijoki River, which has been operational since 1957. The hydropower dam is set to cease operations, marking a transformative step to restore the natural riverine environment. The cessation plan involves diverting water back to the long-unused Piilijoki River, reinstating its ecological role and improve the ecological status of the main Kuusinkijoki River that was disrupted post-dam construction. Our data collection strategy employed field campaigns, capturing high-flow conditions in spring, and low-flow conditions in autumn. Cutting-edge sensors were employed in this endeavour, utilizing the Otter Unmanned Surface Vehicle (USV) for underwater topography scans, Acoustic Doppler Current Profiler (ADCP) for flow characteristic measurements, and water level data loggers for monitoring water level time series. The collected data is then used to create a highly accurate seamless 3D map of the river channel and floodplain. Leveraging this intricate map, we deploy an advanced hydraulic model to comprehensively analyse hydraulic processes and assess flow characteristics following the planned halting of the Myllykoski hydropower dam. Our study's multifaceted objectives include evaluating the spatio-temporal variability of downstream flow in three distinct study sites: (a) an unused natural channel alongside the dam, (b) a man-made channel downstream, and (c) a natural channel downstream, including the riverine lake along the course of the Kuusinkijoki River. Furthermore, we aim to investigate the influence of various flow scenarios on downstream river flow characteristics, analyse spatio-temporal trends in flow dynamics, and identify any significant changes in response to the cessation of dam operations. A crucial aspect of our study involves evaluating the influence of dam halting on river hydrodynamics and ecology using modern sensors and analytical tools.
Fecal recontamination of infiltrated water in Dutch Managed Aquifer Research systems; 20 years of field research
Authors: Cirkel Gijsbert , Borst Lucas , El Majjoui Jamal , van der Schans Martin
Published: March 2024

The western part of the Netherlands depends largely on river water from the Meuse and Rhine rivers for drinking water supply, which is infiltrated into Managed Aquifer Recharge (MAR) systems in the Dutch coastal dunes. Pre-treated river water is infiltrated through open basins and recovered after soil passage for further treatment. This soil passage is a crucial step in drinking water treatment where unwanted microorganisms are efficiently removed. Field studies by Schijven et al (1998,1999), among others, showed that log removal during saturated transport in these systems is more than sufficient to produce microbiologically safe drinking water. Nevertheless, in subsequent years, fecal indicator organisms were still found with some regularity in the abstracted water. It was suspected that this (re)contamination was caused by short circuit flow with feces-contaminated water from ground level through the unsaturated zone. Conducting several field experiments confirmed this hypothesis and provided unique insight into transport behavior and log removal in the unsaturated zone and the role of preferential flow under field conditions. Results of the field trials have been implemented in guidelines for design and management of MAR systems and whether to allow grazing livestock near the MAR-systems for nature management. In this contribution we present the results of a series of field trials, spanning 20 years, providing unique insight in removal of fecal indicator bacteria in unsaturated dune soils and increasing insight in processes responsible for recontamination of infiltrated river water. 
Monsoon precipitation biases in storm-resolving NextGEMS Earth System Models
Authors: Bordoni Simona , Tompkins Adrian M.
Published: March 2024

Global Earth System Models at storm-resolving resolutions (SR-ESM, with horizontal resolutions of ~4km) are being developed as part of the nextGEMS collaborative European EU’s Horizon 2020 programme.  Within the Storms & Ocean theme, we are exploring how resolving convective storms, ocean mesoscale eddies, and air-sea interaction on these scales influences tropical circulations and associated precipitation, and their variability.In this talk, we evaluate the representation of the characteristics of the wet season over core monsoon regions in these SR-ESM, which include assessment of the seasonal cycle of precipitation, the timing of monsoon onset and retreat, and the total accumulated precipitation. These existing biases are compared to those seen in CMIP6 models and  interpreted through the lens of both local and remote moist energy diagnostics based on modern theories of monsoons. Local diagnostics include relative moist static energy (MSE) defined as the difference between local and tropical-mean near surface MSE, which has been recently introduced as a simple measure of the lower and upper-level influences on convective stability and shown to correlate well with monsoon onset dates in both CMIP6 simulations (Bombardi and Boos 2021) and idealized aquaplanet simulations we have conducted. The influence of possible remote biases, such as those of extratropical origin, are explored through analysis of the equator-to-pole MSE gradient. This contrast is central to vertically integrated energy budget frameworks that link changes in monsoonal precipitation to changes in meridional energy fluxes, which in turn scale with the meridional near-surface MSE gradients under diffusive approximations. Biases in this gradient result in smaller or greater advection of low-level MSE into monsoon regions, hence resulting in wet or dry biases, respectively, in monsoonal rainfall.
Tropospheric slant delays interpolating multiple mapping functions
Authors: Navarro Trastoy Angel , Motlagh Zadeh Ghodsiyeh , Vasiuta Maksym , Dumitraschkewitz Patrick , Mayer-Gürr Torsten , Jarvinen Heikki
Published: March 2024

Representing the tropospheric slant delays in geodesy can get complicated due to the inhomogeneity and fast variations of the weather. Mapping functions are the most common used tool for this task, but due to the lack of information when calculating the parameters of the mapping functions, relevant errors could appear. The errors in the zenithal direction come from the limitations of the mapping functions, and in the azimuthal direction come from the asymmetries in the sight-field of the receiver. New representations, as the full skyviews representation made by University of Helsinki, have proven to lead to better results in the computation of GNSS products using orbit processing softwares, but these are expensive, both computationally and in size. In this study, we apply the mapping functions approach using the Least Travel Time ray-tracer with larger amounts of mapping functions per receiver, and a 1-hour update of all the parameters. We believe that a more precise use of the slant delays would lead to a better computaiton of GNSS products, along with a important data assimilation to the weather forecast from the residuals obtained in the Least Squares Adjustment used in the processing. The results show that the error induced when using mapping functions converges quickly to a minimum when we increase the amount of mapping functions used per receiver. The most efficient number of mapping functions is 10, being equidistant (one mapping functions every 36 degrees in azimuth).
Magnetobiochronology of the Izaga section (South Pyrenean foreland basin) and its chronological implications: searching for a potential candidate for the Bartonian GSSP
Authors: Sierra-Campos Pablo , Calvín Pablo , Bernaola Gilen , Montes Manuel , Luzón Aránzazu , Pérez-Landazábal José Ignacio , Gómez-Polo Cristina , Payros Aitor , Mata Maria Pilar , Bellido Eva , Pueyo Emilio L. , Larrasoaña Juan C.
Published: March 2024

Here we introduce a new magnetobiostratigraphic section in the Jaca-Pamplona Basin, the Izaga section, which was studied in order to shed light on the chronology of the Lutetian/Bartonian boundary and the possibility of proposing it to host the Bartonian Global Stratotype Section and Point (GSSP). The Izaga section is located in the northern limb of the eastern termination of the Izaga syncline (South Pyrenean foreland basin) and is composed by a total of 1116 m of marine sediments that include the uppermost 450 m of the Jaca Turbidites and ~660 m of the prodeltaic marls of the Larrés (500 m), Urroz (110 m) and Pamplona (56 m) Formations. The uppermost Jaca Turbidites include the youngest South Pyrenean Eocene Carbonate Megabreccia (SPECM) identified in the basin to date, and the uppermost part of the Larrés Formation hosts ferroan dolomitic nodules whose formation can be linked to early diagenetic methanogenesis. Previously published biostratigraphic data based on planktic foraminifers broadly place the Lutetian/Bartonian boundary within the middle part of the Larrés Formation. A total of 173 magnetostratigraphic sites were sampled throughout the succession with an average 6.5 m spacing. Thermal demagnetization reveals the presence of two stable components: 1) a low temperature component that is identified 80 cm/kyr) in the South Pyrenean foreland basin increased towards the west; 2) that the SPECM found within the Jaca Turbidites extend the processes of SPECM formation well into the Bartonian; and 3) that the ferroan dolomitic nodules found in the uppermost part of the Larrés Formation can be considered as the sedimentological expression of the Middle Eocene Climate Optimum (MECO) in the basin.
An assessment of long-term variability in the NAO, Azores High, and Iceland Low using North Atlantic winds from historical whaling ship logbooks and reanalyses
Authors: Sander Neele , Ummenhofer Caroline C. , Münch Bastian , Giacoppo Tessa , Visbeck Martin , Walker Timothy D.
Published: March 2024

The variability of climate and weather conditions in the North Atlantic and adjacent regions is dominated by multiple modes of climate variability, such as the Atlantic Multidecadal Variability and the North Atlantic Oscillation (NAO). The NAO is one of the region’s most recurrent patterns on interannual to decadal time scales and is often calculated as the pressure difference between the Iceland Low and the Azores High. However, few studies have focused on its centres of action independently, and uncertainties remain about the variations in the associated wind patterns prior to the 20th century. Here, we demonstrate that wind patterns obtained from US whaling ship logbooks from the 19th century from various New England archives align with the predominant wind patterns over the Atlantic region, thus providing invaluable insights into past North Atlantic climate. The logbook data reveals changes in wind speeds that correspond with shifts in the NAO phase and are also seen in reanalysis products. To better understand the NAO’s implications for the winds over the North Atlantic and the individual influences of the Azores High and Iceland Low, we created separate indices for their respective size and positions, allowing us to evaluate their individual behaviour and interactions. Those influences are again compared to the wind patterns provided by the whaling ship logbook data covering the period 1790-1910 CE. There is overall good agreement between the historical data and the reanalysis product, and all differences stay within the variability seen in the individual ensemble members of the reanalysis. Hence, the whaling ship logbook data could be a valuable source to further improve climate indices and thus lead to a better understanding of the long-term context of North Atlantic climate variability.
Combination of Extreme Water Levels and Waves in a Semi-enclosed Sea: Reconstruction of the Baltic Sea 2023 Storm Surge (Babet)
Authors: Adell Anna , Kroon Aart , Almström Björn , Hallin Caroline
Published: March 2024

The October 2023 storm surge, denoted Babet, caused severe flooding and unprecedented damage along the southwestern Baltic Sea coasts. The beginning of October 2023 was dominated by several westerly low-pressure systems over the Baltic Sea region. The abundance of westerly winds pushed water into the Baltic Sea basin through the Danish straits resulting in elevated water levels of +50 cm above normal in the basin. Around the 18th of October the wind direction shifted from west to north and subsequently to east while also increasing in intensity, with mean wind speeds of 25 m/s and gusts exceeding 30 m/s. This gave strong wind setup in the southwestern part of the Baltic Sea and the strong winds generated large waves as well as increasing the water levels further. Notably, the area experienced the most extreme storm conditions in over a century with the storm peak was reached during the night between the 20th to 21st October.We present a study with results of the numerical model simulation using SWAN set up for the southwestern part to the Baltic Sea basin. The simulation combines the wave conditions derived from wind forcing and observed water levels from a network of observation gauges. These levels are compared to historical event statistics from an existing long-term hindcast model of wave climate conditions for the region. Finally, the results of storm surge levels are assessed in relation to observed flooding and erosion impact on natural coastal areas and impact to existing coastal protection.
Measurements of spinning and tumbling rates of micro-plastic fibres
Authors: Giurgiu Vlad , Caridi Giuseppe Carlo Alp , De Paoli Marco , Soldati Alfredo
Published: March 2024

We perform measurements to assess the influence of the wall-normal position of micro-plastic fibres on their spinning and tumbling rates in wall-bounded turbulence. The exper-iments are carried out in a turbulent water channel at a Shear Reynolds number of 720.The used fibres are curved, 1.2mm long, and 10μm in diameter (aspect ratio 120). Theirlength ranges between 4 and 12 Kolmogorov length scales. In the generated flow condi-tions they are inertial-less, neutrally buoyant, and undeformable. We observe their motionwith six high-speed cameras focused in the near-wall region and channel centre. We employand improve upon an established methodology involving the tomographic reconstruction ofeach fibre and subsequent tracking. Leveraging their curved shape, we uniquely identify thetemporal evolution of their orientation, enabling measurements of spinning and tumblingrates. We discuss the uncertainty on the rotation rates based on their shape and angulardisplacement between time-steps. Analysis of converged statistics revealed that the meanand mean square spinning are higher than tumbling rates at both channel centre and near-wall region. These results are novel, considering that previous experiments are restricted tomeasurements of rotation rates of longer straight fibres in homogeneous isotropic turbulenceor to tumbling rates only.
Advanced Discontinuity Detection Algorithm for Geological Formations Using High-Density Point Cloud Data
Authors: Chale Antonin , Jaboyedoff Michel , Derron Marc-Henri
Published: March 2024

Advanced Discontinuity Detection Algorithm for Geological Formations Using High-Density Point Cloud DataAntonin Chale, Michel Jaboyedoff, Marc-Henri DerronGeological hazard analysis relies on precise identification and characterization of discontinuities in rock formations, crucial for evaluating rock stability. While techniques such as Structure-from-Motion (SFM) and Light Detection and Ranging (LiDAR) have significantly advanced high-density 3D point cloud (PC) data acquisition, detecting structural irregularities in complex geological formations remains a challenge. We have developed a new discontinuity detection algorithm that emulates human visual perception. The algorithm employs multi-angle scanning, point cloud optimization techniques, and efficient multiprocessing to comprehensively survey the point cloud. Density maps are generated to identify and determine the orientation of discontinuities, proving effective in both synthetic models and real LiDAR data. The algorithm comprises three primary steps: an initial point cloud scan, density map generation, and visualization of discontinuities with their initial orientation. A secondary scan focuses on the density map, projecting data into a 2D representation to detect a second vector orientation, crucial for identifying discontinuity sets. Thanks to the previous steps we can deduce the orientation of the discontinuity sets. While the algorithm’s capability to handle both synthetic and real-world data sets highlight its potential significance in structural analysis, ongoing work aims to enhance its applicability for larger and more complex datasets. But also, the possibility of extracting the points involved in the different discontinuity sets. References:Adrián J. Riquelme, A. Abellán, R. Tomás, M. Jaboyedoff, (2014)  " A new approach for semi-automatic rock mass joints recognition from 3D point clouds," Computers & Geosciences, Volume 68, 2014, Pages 38-52.Matthew J. Lato, Malte Vöge, (2012) "Automated mapping of rock discontinuities in 3D lidar and photogrammetry models," International Journal of Rock Mechanics and Mining Sciences, Volume 54, 2012, Pages 150-158.
NOAA’s Next-Generation Air Quality Predictions for the United States
Authors: Stajner Ivanka ,   Disaster Relief Supplemental Appropriations Act 2022 Fire 2 project team
Published: March 2024

NOAA is developing the next generation air quality (AQ) prediction system for the United States (U.S.) and global aerosol predictions within the Unified Forecast System (UFS) framework to better represent and forecast impacts of wildfires on AQ and impacts of aerosols globally on weather from hourly to subseasonal scales. A new regional UFS weather model is online coupled with chemistry represented by the EPA’s Community Multiscale AQ (CMAQ) modeling system with Carbon Bond VI and AERO6 mechanisms to form this new UFS-AQM system. Wildfire emissions are specified by satellite-observed  hourly Regional Hourly Advanced Baseline Imager (ABI) and Visible Infrared Imaging Radiometer Suite (VIIRS) Emissions (RAVE). Anthropogenic emissions are based on U.S. EPA’s National Emissions Inventories over the contiguous 48 U.S. states and global inventories elsewhere. Lateral boundary conditions for aerosols are provided by NOAA’s Global Ensemble Forecast System which includes the Goddard Chemistry Aerosol Radiation and Transport (GOCART) module. A bias correction post-processing procedure is included in UFS-AQM to improve prediction accuracy. Testing is performed over a large regional domain covering the U.S., and evaluation is done in near-real time and for retrospective periods. Recent examples indicate much improved representation of impacts of wildfires on AQ predictions, especially during Quebec fires in the summer of 2023.  Some of the planned refinements for UFS-AQM include better representation of plume rise for wildfire smoke and for point source emissions, increased resolution consistent with the Rapid Refresh Forecast System (RRFS), which is under development, and using aerosol lateral boundary conditions from a 6-way coupled atmosphere - ocean -  land - sea-ice - waves - aerosols global UFS system, also under development. Due to challenging computational requirements for UFS-AQM at high resolution, a machine learning emulator is being developed to improve computational efficiency for prediction of chemical transformations and tracer transport. Of most interest for this session, data assimilation capabilities are being developed to constrain initial conditions for pollutant concentrations in UFS-AQM. Observations being assimilated include fine particulate matter (PM2.5) observations from AirNow, VIIRS Aerosol Optical Depth (AOD) retrievals and TROPOspheric Monitoring Instrument (TROPOMI) NO2 retrievals.
An Evaluation of the ADVANCEGeo Partnership Bystander Intervention Model
Authors: Schneider Blair , Bell Christine , Whitmire Stefanie , Hannah Horinek , Hastings Meredith , Barnes Rebecca , Mattheis Allison , Williams Billy , Marin-Spiotta Erika
Published: March 2024

The ADVANCEGeo Partnership program, funded by a National Science Foundation ADVANCE award in 2017, was designed to empower geoscientists to transform workplace climate, and has been recently adapted to other STEMM disciplines as well. To date, the ADVANCEGeo Partnership has led over 230 workshops to institutions across the USA and Europe, in both virtual and in-person formats. A main strategy of ADVANCEGeo for organizational climate change is to enact interventions at the individual and collective level through behavior change education informed by intersectionality and ethics of care frameworks. The program uses a community-based model for bystander intervention and workplace climate education designed to give members of the academic community the knowledge and tools to identify, prevent, and mitigate harm from exclusionary behaviors that directly affect the retention of historically excluded groups in STEMM. Evaluation data from 81 workshops held between 2018-2022 were analyzed using a transtheoretical framework of behavioral change. All of these workshops used a consistent structure and length of presentation (averaging 2.5 hours overall). Thirty six workshops were conducted in-person (44%) and forty five workshops were conducted virtually (56%) using the Zoom platform. The workshops were conducted for a variety of audiences, including institutional leadership, academic departments, professional societies, research groups, and student groups. Each workshop included the same core components, though some materials in the presentation portion were tailored to the needs of the audience as requested. Evaluation results show positive increases in participant knowledge, satisfaction, and intent to change behavior directly after the workshop. An additional follow up survey that was disseminated approximately 6 months after the workshop provides evidence of longitudinal behavior change. These results demonstrate that the ADVANCEGeo Bystander Intervention model design successfully shifts behaviors in workshop participants, with an aim to create more positive workplace climates for all seeking to be a part of STEMM.
Where data-based structure meets process simulation - how heterogeneities relate to lithosphere deformation in the Alps
Authors: Scheck-Wenderoth Leni , Kumar Ajay , Cacace Mauro , Bott Judith , Götze Hajo , Kaus Boris
Published: March 2024

To address the question of how the present-day architecture of the lithosphere and the heterogenous density configuration of the uppermost mantle influence deformation in the Alpine orogenic system we use data-derived 3D configurations as input to dynamic simulations. This includes on the one hand the consideration of a detailed crustal model of the Alpine region and its forelands that resolves first-order contrasts in the thermophysical properties of the crust consistent with available geoscientific observables (active and passive seismic, gravity, geological, geothermal). In addition, we tested an ensemble of configurations of upper mantle thermophysical properties derived from published seismic tomography models. Using a Gibbs-free energy minimization algorithm (https://zenodo.org/records/6538257) we convert the results of regional shear-wave seismic tomography models to temperature models and define the base of the lithosphere and the geometry of slabs in the asthenosphere with a threshold temperature of 1300°C. As a first step we model topography and deformation velocities as resulting from buoyancy-forces driven by a quasi-instantaneous flow resulting from the first-order rheological structure of the lithosphere-asthenosphere system using the open source geodynamic code LaMEM (https://github.com/UniMainzGeo/LaMEM). The simulation results indicate that a slab detached beneath the Alps, but attached beneath the Northern Apennines captures first-order patterns in topography, vertical surface velocities, and mantle flow. The presence of an attached slab beneath the northern Apennines also explains the observed sub-crustal seismicity in contrast to the seismicity in the Alps restricted to the upper-crustal domain.
The Martian Surface Radiation Environment: Zenith Angle Dependence of Fluxes of Different Secondary Particle Species Produced in the Mars Atmosphere
Authors: Khaksarighiri Salman , Wimmer-Schweingruber Robert F. , stubbs Timothy J. , Phipps Phillip H. , Looper Mark D. , Guo Jingnan , Ehresmann Bent , Hassler Donald M. , Matthiä Daniel , Zeitlin Cary , Löwe Jan Leo , Berger Thomas , Löffler Sven , Reitz Günther
Published: March 2024

Understanding the zenith angle dependence of the Martian surface radiation environment is crucial for planning future human exploration missions to Mars. In our previous research (Wimmer et al. 2015; Guo et al. 2021; Khaksarighiri et al. 2023) we extensively studied the zenith-angle dependence of the Martian surface radiation dose rate. Leveraging the same validated radiation model, calibrated with data from the Radiation Assessment Detector (RAD) on Mars, we calculated the flux of secondary downward particles reaching to the surface of Mars from various zenith angles resulting from the interaction of primary particles with the Martian atmosphere. These flux of secondary particles, coming from different zenith angles, can be integrated into a comprehensive topographic map of Mars, providing a detailed depiction of the global radiation landscape.The construction of this radiation map requires careful consideration of various factors, including atmospheric column density, local and large-scale topography offering potential shielding effects, and the input spectrum is affected by heliospheric modulation. Additionally, accounting for seasonal pressure cycles and daily atmospheric surface pressure due to thermal tides is essential. Our model specifically focused on the influence of zenith angle on atmospheric column depth and simulations tailored to the Gale Crater region, a region explored by the Curiosity rover. Applying this methodology allows us to create lookup tables of all secondary particles reaching the Martian surface from various zenith angles and evaluate the atmospheric impact. Employing these matrices alongside the incident spectrum enables the calculation of secondary particle flux from all zenith angles on the Martian surface.This method provides valuable insights into the fluctuations in radiation flux on Mars, facilitating thorough assessments of potential radiation hazards. Mission planners can leverage these data, obtaining vital information to identify secure landing areas and sheltered regions for astronauts on the Martian surface.
Estimating catchment-wide total groundwater storage via space-time kriging provides calibration data for catchment-scale groundwater balance models
Authors: Ejaz Fahad , Wildt Nils , Nowak Wolfgang , Wöhling Thomas
Published: March 2024

Sustainable groundwater management requires accurate and reliable prediction of long-term aquifer water balances. This can be achieved with catchment-scale groundwater balance models such as the recently developed Lumped Geohydrological Model (LGhM) (Ejaz et al., 2022, Journal of Hydrology). As a lumped model similar to hydrological rainfall-runoff models, the LGhM offers high computational speed, lower data requirements compared to spatially explicit groundwater flow models, and suitability for uncertainty analysis. Unlike rainfall-runoff models, LGhMs allow simulating total groundwater storage (TGS) by incorporating additional terms for water budget and dedicated, distributed groundwater storage boxes, inspired by the catchment's aquifer characteristics.Calibration of LGhMs requires both river discharge data and TGS data. LGhMs have shown remarkable performance in synthetic studies (MODFLOW generated data for calibration and validation). The remaining challenge is therefore to obtain TGS data for calibration without full groundwater flow models. Geostatistical methods can help here. They can directly estimate groundwater surfaces from well-based time series, and TGS can then be obtained through spatial aggregation. In this study, we employ space-time kriging to estimate TGS and quantify associated uncertainties. To enhance TGS predictions, we integrate hydrogeological information into the kriging model. These include spatial and temporal trends and soft information inspired by hydrological ideas, such as digital elevation maps, river exchange components, aquifer confinement, and boundary conditions.The Wairau Plain aquifer in New Zealand serves as the testing ground for this approach, where an existing MODFLOW model provides data for calibration and validation for proof of concept. Once validated, this method can be applied in regions without pre-existing groundwater flow models.
Can soil quality in subtropical agriculture be improved by selected forage species? 
Authors: Wickander Niklas , Jørgensen Marit , Dörsch Peter
Published: March 2024

Ethiopia is experiencing severe loss of farmable soil due to high erosion and nutrient depletion. The loss of agricultural land puts pressure on Ethiopian farmers to produce more food on less land. The large number of livestock in Ethiopia further exacerbate the situation, since the high grazing intensity removes plant cover and crop residues and limits the return of organic matter to the soils. Introduction of perennial forage species could break the vicious circle by providing high-quality feed to animals while increasing the input of organic matter to the soil and stimulating soil life. We investigated the effect of four forage species, two grasses, Brachiaria hybrid Cayman and Panicum maximum, and two legumes, Desmodium intortum and Stylosanthes guianensis, in varying mixtures planted according to a simplex design at two locations in Southern and Northern Ethiopia. The field sites were established in six different locations, three in the Sidama and three in the Amhara region. In each region we had one large scale site, at Hawassa and Bahir Dar university respectively, and two smaller farm sites. To assess how the species mixtures affected the soil, we measured the above-ground biomass and took soil samples before and after 2 years of plant growth. We measured labile carbon, nitrification rate, and soil enzymatic activity involved in C, N and P acquisition. The effect of plant input will be compared to time-zero measurements to discern if there are any effects of the species mixtures on the soils. Currently, we see an effect of the total above ground yield of the plots on soil functions, indicating that a higher density of plant coverage influences the soil microbial activity and turnover in the soil.