bluuebunny/crossref_metadata_2025 huggingface dataset:
Integration of artificial intelligence techniques, remote sensing data and field data for simulation of chlorophyll-a concentration in Gorgan Bay
Authors: Khorashadi Zadeh Farkhondeh , Fatemi MohammadReza
Published: March 2024

Chlorophyll-a is an essential component for assessing nutrient content in water resources. Its concentration is influenced by various parameters, including Total Phosphorus (TP), Total Nitrogen (TN), Turbidity (TB), Total Suspended Solids (TSS), temperature, pH and so on. Accurate estimation of chlorophyll-a concentration across different spatial and temporal variations is crucial for assessing the condition of surface water bodies, concerning bacterial and nutrient levels. High chlorophyll-a concentration may compromise aquatic animal health, leading to disease due to increased bacterial concentrations in water.This study aims to develop an estimation model for chlorophyll-a concentration by integrating artificial intelligence models, remote sensing data and field data. The study area includes Gorgan Bay and its contributing rivers. Initially, field data, including water quality parameters, from the water bodies and nearby rivers is analyzed. In addition to field data, remote sensing data, including chlorophyll-a concentration in the Bay, is obtained from the MODIS satellite sensors. As an artificial intelligence technique, the Random Forest (RF) is selected. The input data of the RF model are, therefore, the climate data, water quality data of the incoming rivers and the Bay and the flow of the incoming rivers. The model output is the chlorophyll-a concentration in the Gorgan Bay. The performance of the model is evaluated using different statistical measures. The different techniques are applied to find the most influential input variables for simulating the chlorophyll-a concentration in the Bay. The developed model is capable of predicting chlorophyll-a concentration, supporting improved water quality management of reservoirs (like bays). It can be utilized in locating optimal natural fish farming areas, managing, preserving aquatic ecosystems and enhancing reservoirs water quality.Key words: Chlorophyll-a concentration, Artificial intelligence, Random forest, Remote sensing data, Field data.
Active crustal-scale duplexes and structural wedge in the central part of Greater Caucasus orogen pro-wedge, Georgia
Authors: Alania Victor , Enukidze Onise , Kvavadze Nino , Giorgadze Anzor , Merkviladze Demur , Razmadze Alexander , Xevcuriani Tornike
Published: March 2024

The Greater Caucasus orogen is a typical active double wedge orogen that accommodates the crustal shortening due to far-ﬁeld eﬀects of the collision between the Arabian and Eurasian plates. Our study area is a central part of the Greater Caucasus pro-wedge and represented by the Dzirula-Imereti Uplift zone and epicentral area of Racha 1991 (MW=7) and 2009 (MW=6) earthquakes - Southern Slope of Greater Caucasus. Here we present a new structural model based on interpreted seismic profiles and regional balanced cross-sections. Seismic reﬂection data reveals the presence of a basement structural wedge, fault-related folds, triangle zones, and active- and passive-roof duplexes. The most important observation from our study is that the Dzirula massif is a basement wedge and forms a triangle zone. The Dzirula structure is defined by mid-crustal detachment and a roof thrust, constituting a tectonic wedge with a passive back thrust. The regional balanced cross-sections show that the Racha earthquakes are related to crustal-scale duplexes.Acknowledgments. This work was funded by Shota Rustaveli National Science Foundation (SRNSF) (grant# FR-21-26377).
Mapping soil multifunctionnality for urban planning and development: from research to "no net land take" 
Authors: Le Guern Cecile , Deslandes Benjamin , Duvigneau Clémentine , Basuyau Mathilde , Lemot Antoine , Laroche Bertrand , Branchu Philippe
Published: March 2024

The French R&D MUSE project developed a methodology to map the potential multifunctionnality of unsealed soils based on existing data at national scale, in order to consider this information in urban planning. This method gives a partial idea of soil health. The data on rural areas allow mapping 4 ecological soil functions: potential of carbon storage, water storage, agronomic potential, and biodiversity reservoir. The lack of soil maps on urban area conducted to propose a simplified approach. The methodology was developed in collaboration with 3 pilot territories. The aim of this presentation is to establish feedback on the application of the methodology on various geographical and pedo-climatic contexts.The analysis is carried out on more than 10 cases including Rennes Métropole, Ris-Orangis and Savoie Métropole, by checking the objectives of the application, the appropriation by operators and the adaptations proposed.The feedback shows the ability to identify zones to be preserved, developed or disartificialised by crossing with other data. More detailed soil maps contribute to gain precision and are mandatory to design development projects. New methodological developments are proposed also to map soil multifunctionnality in urban areas. The integration of soil quality to reach the "no net land take" target is also in progress. It takes into account a moderation of the potential soil functions by knowledge on pollution risks and remediation projects.The MUSE methodology is getting more and more applied in France, although its application needs some technical skills on soils and geomatics. In this frame, an automation script was developed to standardise the production of the 4 ecological soil function maps. It can be applied at various scales, according to the precision of the available data. The feedback underlines the need to wider characterise urban soil and to bank further the acquired data to improve the knowledge on urban soils. 
Effect of climate policies on the long-term equilibration of glaciers
Authors: Zekollari Harry , Schuster Lilian , Hock Regine , Marzeion Ben , Maussion Fabien , GlacierMIP3 participants the
Published: March 2024

Glaciers adapt to changing climatic conditions by losing or gaining mass, translating into a geometry change. Due to ice-dynamical processes within glaciers that gravitationally transport mass from high to low elevation, the adaptation of the glacier geometry to changing climatic conditions is not immediate but requires timescales ranging from decades up to millennia. As a consequence, today glaciers are in imbalance with current climatic conditions and will respond on timescales that extend beyond the 21st century time horizon that is typically considered in today’s glacier evolution studies.As part of the Glacier Model Intercomparison Project – Phase 3 (GlacierMIP3), a global glacier modelling community effort, we quantify how glaciers will stabilize under a wide range of climatic conditions. Using 8 large-scale glacier models, we estimate the committed loss of all glaciers on Earth outside the ice sheets under current climate conditions (corresponding to +1.2°C above pre-industrial levels) and their long-term stabilization under various policy-relevant global warming scenarios, such as +1.5°C and +2°C (Paris agreement), and the projected warming following current policies (+2.7°C). The forcing is derived from historical and future simulations (3 SSP emission scenarios) from 5 GCMs, from which climatic conditions for given time periods are continuously repeated over millennial time scales, leading to an eventual glacier stabilization. We find that the committed glacier loss is substantial, with about one third of global glacier volume to be lost under current climatic conditions. The final (steady state) global glacier volume strongly depends on future temperatures, with an increase in the order of 2-3% of global glacier loss per 0.1°C warming. We also evaluate regional differences and quantify the time scales involved in glacier stabilization. Here we find that the topographical features such as the elevation range and the surface slope of glaciers play an important role.
Late Pliocene and Early Pleistocene CO2 and CH4 from ice cores from the Allan Hills, Antarctica
Authors: Marks Peterson Julia , Shackleton Sarah , Severinghaus Jeffrey , Brook Edward , Higgins John , Kurbatov Andrei , Yan Yuzhen , Buizert Christo , Kalk Michael , Beaudette Ross , Carter Austin , Epifanio Jenna , Morgan Jacob
Published: March 2024

Currently, chronologically discontinuous ice cores from the Allan Hills Blue Ice Area (BIA), Antarctica, are our only direct insight into the atmospheric composition of periods beyond the continuous ice core record (800 ka BP). An accurate and precise greenhouse gas history beyond 800 ka would aid understanding of the mechanisms involved in the climatic transitions across the late Pliocene and early Pleistocene. Here we present carbon dioxide (CO2) and methane (CH4) results from a new core from the Allan Hills BIA (ALHIC1901). The bottom 25 m of ALHIC1901 contain 52 sampled depths with co-registered 40Aratm dates (Shackleton et al. in prep), measurements of δD of ice, δ18Oatm, and concentrations of CO2 and CH4 in trapped air. Of these samples, 25 are older than the continuous ice core record, with ages from 821 ± 80 ka to 2700 ± 270 ka. The bottom meter contains ice from the Pliocene with ages from 2700 ± 270 ka to 4000 ± 400 ka. The carbon isotope ratio of CO2 (δ13C-CO2) was measured on 18 samples to examine the possibility of input of non-atmospheric CO2 from oxidation of organic matter. Our results indicate that CO2 and CH4 levels were similar in the early Pleistocene to those found for the last 800 ka. A small decline of approximately 20 ppm is seen in CO2 across the Pleistocene, and no secular trend is observed in CH4. Pliocene-aged samples appear to contain a mixture of atmospheric CO2 and CO2 derived from respiration of organic matter at the glacier bed. Using an isotope mixing model we estimate that atmospheric CO2 was lower than 350 ppm at ~3.1 Ma,
A Case Study on Agricultural Drought Monitoring using ASCAT Surface Soil Moisture at 6.25 km sampling over Eastern Africa
Authors: Muguda Sanjeevamurthy Pavan , Vreugdenhil Mariette , Hahn Sebastian , Massart Samuel , Villegas-Lituma Carina , Lindorfer Roland , Wagner Wolfgang
Published: March 2024

Agriculture faces increased challenges due to intense and frequent droughts caused by climate change. Accurate and timely monitoring of drought conditions, therefore, becomes paramount to taking quick and decisive actions towards its impact mitigation. Agricultural droughts occur due to prolonged periods of low rainfall and high temperatures, which lead to soil moisture deficits, increasing plant water stress and adversely affecting crops. This study explores the potential use of a new demonstrational ASCAT surface soil moisture (SSM) product sampled at 6.25 km provided by EUMETSAT's Satellite Application Facility on Support to Operational Hydrology and Water Management (H SAF) to monitor agricultural droughts. The study focuses on East Africa, a region severely affected by consecutive years of droughts, resulting in acute food and water shortages that have put the livelihood of millions at risk. This study offers a preliminary quality assurance of the ASCAT SSM 6.25 km product with ERA5-Land and ESA CCI (passive) SSM, respectively, focusing on the effects of subsurface scattering and changes in land cover. We first conducted a correlation analysis to gain insights into the general quality and subsurface scattering effects in arid regions of East Africa. Furthermore, to address significant wetting trends caused by land cover changes, which were previously observed in the H SAF ASCAT SSM 12.5 km climate data record product (H119), the dry and wet backscatter reference parameters are estimated on a yearly basis as part of the TU Wien change detection algorithm. The effectiveness of this novel approach is then quantified by comparing trends of ASCAT SSM 6.25 km product with trends of the other SSM datasets.To assess the potential for agricultural drought monitoring, a convergence of evidence approach was used. Here, the ASCAT SSM 6.25 km anomalies are compared to anomalies in CHIRPS precipitation, LSA SAF (Land Surface Analysis of EUMETSAT) land surface temperature, and CGLS (Copernicus Global Land Service) vegetation datasets for previously recorded drought events. We also generated two drought indicators based on anomalies using the ASCAT SSM 6.25 km product: SMAPI (Soil Moisture Anomaly Percentage Index) and Z-scores, which were evaluated with SPEI (Standardised Precipitation and Evapotranspiration Index) to assess the similarity in spatial patterns of droughts.Our assessments show that the demonstrational ASCAT SSM 6.25 km product corresponds well with other SSM datasets. Moreover, the drought indicators derived from it effectively capture precipitation deficits and increased land surface temperature compared to SPEI (drought conditions), indicating its potential for agricultural drought monitoring.
Flipping the cost of tipping? Economic impacts of reduced AMOC carbon drawdown
Authors: Schaumann Felix , Alastrué de Asenjo Eduardo
Published: March 2024

Social cost of carbon (SCC) research has paid increasing attention to climate tipping points and feedback mechanisms. The weakening of the Atlantic Meridional Overturning Circulation (AMOC) is currently treated as a global benefit, as it would lower Northern Hemisphere surface temperatures and thereby offset parts of global warming and its associated economic damages. We add to the literature on economic impacts of AMOC weakening by, for the first time, adding a second impact channel which acts through carbon cycle changes. A weaker AMOC directly leads to a reduced export of carbon-rich surface waters to the deep ocean, such that, conversely, more carbon remains in the atmosphere and acts to increase global temperatures and associated economic damages. By drawing on carbon cycle feedback and freshwater hosing experiments, we provide climate modelling evidence on the magnitude of this AMOC-induced carbon feedback, and develop an emulator with which to include these estimates into a simple integrated assessment model. Based on these IAM calculations calibrated to ESM results, we find that carbon cycle feedbacks lead to an SCC increase of around 1%, which is in the same order of magnitude as the SCC decrease caused by AMOC-induced temperature changes. Taking into account this carbon effect could thus flip the overall economic effect of AMOC weakening from a net benefit into a net cost.
Spatial and Temporal Patterns of Vegetated Microclimates from Synergistic Mobile and Stationary Measurements
Authors: White Loren
Published: March 2024

Connections between microclimate and ecological systems are widely recognized. Recently, the relevance of microclimate to ecological microrefugia has been highlighted in relation to endangered species and relict habitats under changing large-scale climate forcing and anthropogenic habitat losses. While truly undisturbed natural environments are rare, the broader category of non-urban vegetated land is much more widespread globally than urban surfaces. Therefore within-canopy microclimatic processes are globally important for interactions with the macroclimate. Aside from local topographic and hydrologic forcing, the structure, phenology, and behavior of vegetation canopies (forest, woodland, shrub, grassland) interact with radiative, wind, and evapotranspiration processes to modulate and drive site microclimate. To effectively sample the spatiotemporal characteristics of microclimates, it is suggested that numerical modelling, mobile transects, and surface parameters (terrain, vegetation) should be used to design measurement strategies. In particular, the very high spatial resolution of within-canopy measurements from mobile pedestrian measurements are relevant to compare spatial variations to forcing from vegetation cover, terrain, and surface moisture.A series of microscale measurements of temperature, humidity, and radiation has been launched using a pedestrian mobile system previously developed in the CHEESEHEAD2019 field campaign, in tandem with strategically located stationary sensors over a variety of environments. The initial five sites are located in upland, floodplain, and riverine areas of Mississippi. Other sites with greater topographic relief will be investigated in Maryland and Missouri.
Arctic Sea Ice Loss, Long-Term Trends in Extratropical Wave Forcing, and the Observed Strengthening of the QBO-MJO Connection
Authors: Hood Lon , Hoopes Charles A.
Published: March 2024

A modulation has been identified of the tropical Madden-Julian oscillation (MJO) by the stratospheric quasi-biennial oscillation (QBO) such that the MJO in boreal winter is ~ 40% stronger and persists ~10 days longer during the easterly QBO phase (QBOE) than during the westerly phase.  A proposed mechanism is reductions of tropical lower stratospheric static stability during QBOE caused by (1) the QBO induced meridional circulation; and (2) QBO influences on extratropical wave forcing of the stratospheric residual meridional circulation during early winter.  Here, long-term variability of the QBO-MJO connection and associated variability of near-tropopause tropical static stability and extratropical wave forcing are investigated using European Center reanalysis data for the 1959-2021 period.  During the most reliable (post-satellite) part of the record beginning in 1979, a strengthening of the QBO-MJO modulation has occurred during a time when tropical static stability in the lowermost stratosphere and uppermost troposphere has been decreasing and extratropical wave forcing in early winter has been increasing.  A high inverse correlation (R = -0.87) is obtained during this period between early winter wave forcing anomalies and wintertime tropical lower stratospheric static stability.  Regression relationships are used to show that positive trends in early winter wave forcing during this period have likely contributed to decreases in tropical static stability, favoring a stronger QBO-MJO connection.  As shown in previous work, increased sea level pressure anomalies over northern Eurasia produced by Arctic sea ice loss may have been a significant source of the observed positive trends in early winter wave forcing.
The Europa Clipper MASPEX Investigation
Authors: Waite J. Hunter , Burch James L. , Brockwell Tim , Young David T. , Miller Kelly , Glein Christopher R , Wyrick Danielle Y. , Teolis Benjamin D. , Bolton Scott J. , Choukroun Mathieu , McGrath Melissa A. , McKinnon William B. , Mousis Olivier , Sephton Mark A. , Shock Everett , Zolotov Mikhail Yu , Persyn Steven C. , Stone John M , Perryman Rebecca , Ray Christine ,   MASPEX Science and Instrument Teams
Published: March 2024

The MAss Spectrometer for Planetary EXploration (MASPEX) is a multi-bounce time-of-flight neutral gas mass spectrometer with unprecedented spaceborne mass resolution and sensitivity. It is capable of measuring and identifying minor and trace gases requiring mass resolution of m/Δm ~ 25,000 at abundances of parts-per-million in Europa’s exosphere. Exospheric sources of gases include exsolved, sublimed, sputtered, and radiolytically produced volatiles from Europa’s surface and interior. These gases can be used to characterize surface composition and identify volatiles outgassed from Europa’s interior. Of particular relevance in characterizing Europa’s habitability are the ratios of organic compounds such as alkanes, alkenes, alkynes, alcohols, ethers, aldehydes, amides, amines, and nitriles that undergo chemical transformations, which can be used to determine oxidation states, pH, temperature, and free energy availability of an interior ocean, perched lake, or a gas source region in the ice shell (e.g., a diapir). This paper presents: 1) the principles and ground-calibrated performance of the MASPEX instrument that is now integrated onto the Europa Clipper spacecraft and planned to be launched in October of 2024, 2) the planned scientific investigation and its critical role in the study of Europa’s habitability, 3) the operational plans, and 4) the anticipated data products from the MASPEX investigation. The paper will also discuss the complexity of the investigation and its requisite need for the acquisition of supporting geochemical, impact fragmentation, and sputtering/radiolytic data sets that help to characterize the geochemical reaction framework and the anticipated modification of chemical species due to impacts with the instrument’s thermalizing chamber, and from radiolysis and sputtering. In the latter context we present the science team’s efforts to generate the necessary data sets, and we encourage interested scientists to contribute to this important endeavor, which is essential for the maximum success of the MASPEX investigation.
Predicting Fire Aerosols and their Impact on Subseasonal to Seasonal Weather Forecasts in NOAA’s Global Aerosol Forecast Systems
Authors: Zhang Li , Grell Georg , Bhattacharjee Partha , Sun Shan , Jensen Anders , Schnell Jordan , Li Haiqin , Li Yunyao , Baker Barry , Henderson Judy , Ahmadov Ravan , Bernardet Ligia , Tong Daniel , Sun Ziheng , Pan Li , Fu Bing , Montuoro Raffaele , He Jian , Schwantes Rebecca , Wang Siyuan ,   NOAA team
Published: March 2024

Recognizing the uncertainties associated with fire emission, a crucial factor influencing the fire aerosol prediction, we have initiated studies to improve fire emission for subseasonal to seasonal (S2S) forecasts. Two global aerosol/chemistry forecast models are currently under development and have been fully coupled with the Unified Forecast System (UFS), encompassing ocean, sea ice, wave and land surface components for S2S forecasts at NOAA. One is UFS-Aerosols: the second-generation UFS coupled aerosol system, which embeds NASA’s 2nd-generation GOCART model in a National Unified Operational Prediction Capability (NUOPC) infrastructure, has been collaboratively developed by NOAA and NASA since 2021. It is planned to be implemented into the Global Ensemble Forecast System (GEFS) v13.0 for ensemble prototype 5 (EP5) experiments early this year. The other one is UFS-Chem: an innovative community model of chemistry online coupled with UFS, developed collaboratively between NOAA Oceanic and Atmospheric Research (OAR) laboratories and NCAR. The aerosol component implemented into UFS-Chem is based on the current operational GEFS-Aerosols v12.3 and utilizes the Common Community Physics Package (CCPP) infrastructure with updates to wet deposition, dust and fire emission, etc. Both these two global aerosols forecast models include the direct and semi-direct radiative feedback from online aerosols prediction. Various global fire emission data, as well as their ensemble product, are employed to quantify the uncertainties associated with fire aerosol prediction. The capabilities of UFS-Aerosols and UFS-Chem in medium-range and S2S predictions of fire aerosol are assessed and compared using observations from reanalysis data, ground-based measurements, and satellite data. Additionally, preliminary blending and machine learning methods have been developed to predict fire emission and improve the S2S prediction. 
Trends and variability of lake surface water storage in the source region of the Yellow River based on deep learning
Authors: Han Weixiao , Huang Chunlin , Wang Weizhen , Hou Jinliang , Schaepman-Strub Gabriela , Gu Juan , Peng Yanfei , Zhang Ying , Dou Peng
Published: March 2024

The source region of the Yellow River is one of the main regions of the Asian water tower, lakes storing standing or slowly flowing water that provides essential ecosystem services of fresh water and food supply, waterbird habitat, cycling of pollutants and nutrients, and recreational services. Lakes are also key components of biogeochemical processes and regulate climate through cycling of carbon. Thus the estimation of trends and variability of the lake surface water storage is very critical, the direct human activities (damming and water consuption) and the natural factors (precipitation, runoff, temperature and potential evaporation) is gradually changing this environmentally sensitive region, especially the glacier retreat and permafrost thawing partially drive alpine lake expansion.The objective is mainly estimating the trends and variability of lake surface water storage using the deep learning module and long-term multi-source remote sensing data from the source region of the Yellow River. Optical remote sensing time-series images (Landsat 5-9, MODIS, and Sentinel-2) are employed to generate high-resolution, complete and closed lake surface shorelines and areas based on the Deep Convolutional Generative Adversarial Networks (DCGAN) deep learning method. Additionally, radar altimeters (GFO, T/P, Jason-1/2/3, Sentinel-6, ERS-2, Envisat, Cryosat-2, Saral/AltiKa, Sentinel 3/SRAL, ICESat, and ICESat-2) are utilized to recover lake water levels through the application of the Spatial-Temporal Graph Neural Networks (ST-GAN) deep learning method, providing insights into the long-term changes in lake water surface storage from 1992 to 2022. The study aims to assess the contributions of human activities and natural factors, and provids the valuable guidelines for water resource management.
A Comprehensive Indicator Based Vulnerability Assessment Method for School Education System: A Case Study of Sundarban Delta, India
Authors: Pal Anushree , Tsusaka Takuji W. , Sundaram Mohana , Ahmad Mokbul Morshed , Nguyen Thi Phuoc Lai
Published: March 2024

ABSTRACTNatural hazards significantly impact school education, particularly in developing countries owing to their low coping capacity to hazards. The world’s 10 percent of tropical cyclones are experienced by Indian coastlines, together with the high probability of extreme rainfall events often leading to flood hazards. A comprehensive literature review highlighted the needs for thorough research on the differential impacts of climatic hazards on Sundarbans school education system and its societal linkages for adaptation strategies, hence promoting the resilient community.This research aims to explore the impacts of multiple hazards and associated disruptions in school education, and attempts to identify determinants of resilience of school education to multiple hazards. The study aims to formulate an indicator library for vulnerability assessment of school education in the deltaic region. The research comprises of the conceptual background of vulnerability assessment, the indicators for education systems in the delta, the methodology for indicator library, and the indicator library table for school education systems in a comprehensive way. The study aims at developing a comprehensive library of school vulnerability indicators that will academically contribute as a reference for future researchers in the field of school vulnerability assessment.
Early evidence of land subsidence in Kathmandu Valley
Authors: Khatiwada Bhaskar , Rana Sanjeev , Khanal Anoj , Khatiwada Bibek , Tiwari Nabin , Mishra Bhogendra
Published: March 2024

Land subsidence in Kathmandu Valley has been recorded since 2003. The major cause of the Kathmandu valley subsidence is still unidentified and the subsiding depth or layer is not clear yet. Published research work has revealed the positive correlation between subsidence and sediment thickness of the valley. Kathmandu Valley, with a heterogeneous sediment thickness and different depths of bedrock, creates favorable conditions for differential settlement.This study is focused on understanding and analyzing the early evidence of land subsidence in different parts of Kathmandu Valley, with direct field observations. Developing empirical relationships to better understand the underlying causes of land subsidence, primarily, multiple deep tubewells (DTW) sites across the valley were observed with the aim of analyzing changes in tubewell head and the impact of subsurface geology and tubewell lithology being studied. Tubewell constructed over bedrock shows the upheaval of the tubewell head in UN Office, Pulchowk, Jagdal Gulma, Chhauni, Prime Hotel, Thamel, where depth to bedrock is 126, 100, and 210 meters respectively. Tubewell upheaval has been recorded since 2017 in Pulchowk and Chhauni and since 2020 in Thamel with the rate of tubewell upheaval is similar to land subsidence recorded from InSAR and DGPS surveys. A similar pattern of tube well upheaval is visualized in and around the surrounding area, where tubewells are constructed over bedrock. In the same area, tubewells constructed on soil subsurface with relatively shallow depth remain the same. A 550 meter long horizontal surface crack around the Manbhawan area indicates the differential settlement of ground surface due to land subsidence. However, no strong evidence is recorded around the central part of the valley floor, where the depth of bedrock is deep.The evidence recorded by tubewell upheaval at Pulchowk, Chhauni and Thamel validates the regional compaction of sediment layers deposited over the bedrock and the surface crack around the Manbhawan area validates the differential settlement due to change of subsidence rate over the same area. No change of tubewell head in shallow tubewell in the same area validates the deep aquifer compaction due to groundwater extraction and sediment load.
Towards Fully Distributed Rainfall-Runoff Modelling with Graph Neural Networks
Authors: Nelemans Peter , Bentivoglio Roberto , Buitink Joost , Meshgi Ali , Hrachowitz Markus , Dahm Ruben , Taormina Riccardo
Published: March 2024

Fully distributed hydrological models take into account the spatial variability of a catchment, allowing for a more accurate representation of its heterogeneity, and assessing its hydrological response at multiple locations. However, physics-based fully distributed models can be time-consuming when it comes to model runtime and calibration, especially for large-scale catchments. On the other hand, deep learning models have shown great potential in the field of hydrological modelling, outperforming lumped rainfall-runoff conceptual models, and improving prediction in ungauged basins via catchment transferability. Despite these advances, the field still lacks a multivariable, fully distributed hydrological deep learning model capable of generalizing to unseen catchments. To address the aforementioned challenges associated with physics-based distributed models and deep learning models, we explore the possibility of developing a fully distributed deep learning model by using Graph Neural Networks (GNN), an extension of deep learning methods to non-Euclidean topologies including graphs and meshes.We develop a surrogate model of wflow_sbm, a fully distributed, physics-based hydrological model, by exploiting the similarities between its underlying functioning and GNNs. The GNN uses the same input as wflow_sbm: distributed static parameters based on physical characteristics of the catchment and gridded dynamic forcings. The GNN is trained to produce the same output as wflow_sbm, predicting multiple gridded variables related to rainfall-runoff, such as streamflow, actual evapotranspiration, subsurface flow, saturated and unsaturated groundwater storage, snow storage, and runoff. We show that our GNN model achieves high performance in unseen catchments, indicating that GNNs are a viable option for fully distributed multivariable hydrological models capable of generalizing to unseen regions. Furthermore, the GNN model achieves a significant computational speedup compared to wflow_sbm. We will continue this research, using the GNN-based surrogate models as pre-trained backbones to be fine-tuned with measured data, ensuring accurate model adaptation, and enhancing their practical applicability in diverse hydrological scenarios.
Modelling energetic particle transport with the PARADISE code
Authors: Husidic Edin , Wijsen Nicolas , Poedts Stefaan , Vainio Rami
Published: March 2024

Numerical tools for realistic modelling of energetic processes in the heliosphere, with the prospect of forecasting space weather, are in high demand. Of particular interest are solar energetic particles (SEPs), comprising high-energy charged particles linked to solar eruptive phenomena. During large SEP events, protons can be accelerated to energies ranging from tens of MeV up to a few GeV per nucleon, posing a dangerous threat to astronauts and spacecraft. While the precise acceleration mechanism behind SEP events is still an open challenge, observations indicate that the intensities of SEPs are highly influenced by the large-scale solar wind configuration. Transient structures such as coronal mass ejections (CMEs) or stream interaction regions (SIRs) perturb the interplanetary (IP) magnetic field, ultimately altering the transport of SEPs. In this context, we share recent results obtained with the energetic particle transport code PARADISE. By utilising realistic and complex solar wind configurations derived from magnetohydrodynamic (MHD) models such as EUHFORIA and the MPI-AMRVAC-based model Icarus, the code solves the focused transport equation in a stochastic manner to obtain spatio-temporal intensity distributions of SEPs in the inner heliosphere. Our studies focus on particle acceleration at IP shocks related to CMEs and SIRs.
Modelling Glacial Isostatic Adjustment in Firedrake 
Authors: Scott William , Hoggard Mark , Ghelichkhan Sia , Gibson Angus , Kramer Stephan , Davies Rhodri
Published: March 2024

Melting ice sheets transfer water from land into ocean basins. The resulting sea-level rise is, however, highly spatially non uniform and time dependent due to complex feedbacks between viscoelastic deformation of the solid Earth in response to these evolving surface loads and coupled perturbations in the gravitational field and rotation axis. Together, these processes are referred to as Glacial Isostatic Adjustment (GIA) and accurate models of GIA are crucial for robust interpretation of both modern and paleo measurements of sea-level change and ice-mass balance. 

A limitation with many existing GIA modelling codes is their inability to incorporate lateral variations in Earth structure. Nevertheless, there is mounting evidence for the presence of significant lateral changes in mantle viscosity, for example beneath West Antarctica, that give rise to complex interactions between rates of surface rebound, sea-level change and ice retreat. Understanding these processes requires development of a new generation of GIA codes capable of handling such variations in rheology at increasingly fine spatial and temporal evolution. 

In this presentation, we will introduce a new project to model GIA using the Firedrake finite element framework and present results for several community benchmarks. Firedrake leverages automatic code generation to create a separation of concerns between employing the finite-element method and implementing it. This approach maximises the potential for collaboration between computer scientists, mathematicians, scientists and engineers and enables sophisticated high performance simulations. A key advantage of Firedrake is the automatic availability of sensitivity information through the adjoint method, allowing us to investigate inverse problems. We are developing an open-source tool highly suited to the challenge of modelling complex Earth structure in GIA, building on the Firedrake-based G-ADOPT project for mantle convection. We envision that future applications might include, but are not limited to, investigating non-linear and transient rheologies, feedbacks between sea-level and glacier dynamics, and reducing uncertainty on sea-level projections into the future. 
Exploring the effect of abrupt society transformation on flood responses among farmers in China using an agent-based model
Authors: Liu Chang , Kawasaki Akiyuki , Shiroyama Tomoko
Published: March 2024

As the longest river in Asia, the Yangtze River has shown its impact on human societies with floods recorded since 12th century. In 1931, the Yangtze River has manifested its force again with one of the deadliest floods ever recorded in Chinese history, causing 422,499 deaths, damages to more than 25.2 million people and 58.7 billion m2 farmland. Similar flood occurred again in 1954, resulting in 31,762 deaths, damages to 18.9 million people and 31.7 billion m2 farmland. Researches have shown that 1954 flood being larger and higher compared to 1931 flood. However, it is still unclear for what reason that a more severe flood leading to less damage. Here we assumed such discrepancy could be ascribed to drastic society transformation in 1930s and 1950s (e.g., increase of absentee landlords in 1930s, and the land reform movement in 1950s). To further understand its effect on flood responses among farmers, an agent-based model named Farmer Landlord Inundation Production (FLIP) was developed. The model was constructed by simulating each farmer’s movement decision during floods based on different hydrological and economic circumstances. Then it was applied to the simulation of multiple villages in Hubei Province (along the mid-reach of Yangtze River) on the basis of reconstructed daily inundation from July to September, 1931 and 1954. Our results have shown that the farmers’ mitigation decision was highly sensitive to the relief amount and distribution timing, indicating a possible decrease of refugees from 70% to 15% between 1931 and 1954. Overall, we demonstrate how society transformation are likely to affect the damage of and response to floods in a different (sometimes more important) way from traditional countermeasures in modern Chinese history. We anticipate our research to be a starting point towards deeper understanding of human and hazard, and the knowledge of which is likely to be applicable to many other regions and times.
The advantages and considerations of applying dual tracers in SWPP tests 
Authors: Lee Nam-Ryeong , Baek Ji-Young , Lee Kang-Kun
Published: March 2024

The Single-Well Push-Pull (SWPP) test is a cost-effective tracer test that has been widely used for aquifer characterization. There is an advantage in concurrently utilizing heat and solute tracers for a comprehensive understanding of the hydraulic and thermal characteristics of the aquifer. However, the application of both tracers in SWPP tests has yet to be commonly used due to their particularity in setting experimental conditions such as drift time and the use of chaser. In this research, dual-tracer SWPP tests were conducted in a laboratory scale using sand (d50 = 0.84 mm, U = 2.06) under six different seepage velocities (vs = 17.5 ― 59.7 m/d), with relative drift time as the variable. As tracers, a sodium chloride solution with a concentration of 1000 ppm and a temperature difference of approximately 6℃ from the background water temperature was employed. Obtained EC and temperature time series data were analyzed by several analytical models. The estimates from analytical models (seepage velocity, porosity, volumetric heat capacity) were compared to those from measurements to evaluate the applicability of a single analytical model on dual-tracer SWPP test. Preliminary experimental results showed that slower velocities and shorter drift times resulted in higher recovery rates but also led to larger error rates in estimates for the solute tracer. Building upon a solute tracer, more accurate analytical models suitable for the current experimental setup were identified, and subsequently extended to the heat tracer for further analysis. Based on the interpretation of both tracers, appropriate test conditions for dual-tracer SWPP tests will be proposed. We anticipate to offer a deeper understanding of the benefits and considerations associated with the combined use of heat and solute tracers for the thorough evaluation of aquifer characteristics during push-pull tests.Keywords: Single-well push-pull test, Laboratory experiments, Heat tracer, Solute tracerAcknowledgements : This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2022R1A2C1006696). This work was also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (No. 2022R1A5A1085103). This work was also supported by the Nuclear Research and Development Program of the National Research Foundation of Korea (NRF-2021M2E1A1085200).
Mid-Holocene ice history inferred from GIA-induced crustal motion around Lützow-Holm Bay, East Antarctica
Authors: Okuno Jun'ichi , Hattori Akihisa , Doi Koichiro , Irie Yoshiya , Aoyama Yuichi
Published: March 2024

The history of ice melting and the viscoelastic properties of the mantle heavily influence Antarctic crustal deformation caused by Glacial Isostatic Adjustment (GIA). The interaction between ice history and mantle viscosity further complicates the complex Antarctic GIA. Nonetheless, geodetic observations, such as GNSS, are crucial for constraints on the GIA model parameters.For over two decades, the Japanese Antarctic Research Expedition (JARE) has been using GNSS and absolute gravity measurements to obtain data along the coast of Lützow-Holm Bay, primarily at Syowa Station. This study examines the geodetic signals associated with GIA from observations along the Lützow-Holm Bay coastline in East Antarctica, and we also conduct GIA simulations based on the recent report of rapid ice thinning in the target region during the mid-Holocene.Based on geomorphological surveys and surface exposure ages, Kawamata et al. (2020: QSR) showed that the region experienced rapid ice thinning of over 400 m from about 9 to 6 ka. Representative deglaciation models, such as ICE-6G, do not account for this rapid thinning process. Therefore, we investigate the variability of the geodetic signals using the ice history, including this rapid thinning. Our predictions demonstrate that incorporating the modified ice history results in consistent outcomes with the observations. This finding supports the notion that rapid ice melting occurred in the Holocene and suggests that geodetic observations can help constrain this region's ice sheet melting process. Additionally, we will present a possibility of the readvance following the rapid retreat based on the precise GIA modelling.
Observations of different effects of an anti-cyclonic eddy on internal solitary waves in the South China Sea 
Authors: Xu Jiexin
Published: March 2024

Internal solitary waves (ISWs) were observed by mooring data in the South China Sea in August and September 2014. Normally the arrival pattern of ISWs is relatively regular and the ISW amplitudes have a positive correlation with the magnitude of semidiurnal tidal currents near the Luzon Strait. However, the ISW amplitudes observed in the second spring tide of September are significantly large when an anti-cyclonic eddy is passing the mooring. When an ISW passes the eddy center, its amplitude reduces to nearly zero, but when an ISW passes the eddy edge, its amplitude increases by 50%. A deepened thermocline always damps the ISW amplitudes, whilst the eddy-induced background currents at different locations may have varied effects on the ISW amplitudes, e.g., the background current at the eddy center tends to damp the ISW amplitude but that at the eddy edge amplifies the ISW amplitude. The different effects of a deepened thermocline and eddy-induced background currents near the eddy edge may damp or amplify the ISW amplitude.
A study of very high resolution visible spectra of Titan: Line characterisation in visible CH4 bands and the search for C3
Authors: Rianço-Silva Rafael , Machado Pedro , Martins Zita , Lellouch Emmanuel , Loison Jean-Christophe , Dobrijevic Michel , Dias João , Ribeiro José
Published: March 2024

The atmosphere of Titan is a unique natural laboratory for the study of atmospheric evolution and photochemistry akin to that of the primitive Earth (1), with a wide array of complex molecules discovered through infrared and sub-mm spectroscopy (2) (3). Here, we present the results of the exploration of original, ground-based, very high-resolution visible spectra of Titan, obtained with VLT-UVES (4). We have developed a new, Doppler-based line detection method which allowed to retrieve an empirical, high resolution (R = 100.000) line list of methane between 525 nm and 618 nm, for which no similar line lists are yet available (5), identifying and characterising more than 90 new high energy CH4 absorption lines at low temperature (T = 150 K).Furthermore, we searched for the predicted, but previously undetected carbon trimer molecule, C3, (6) (7), on the atmosphere of Titan, at its 405.1 nm band, by comparing VLT-UVES Titan spectra with a line-by-line (8) model spectrum of Titan’s atmosphere with C3. Our results are consistent with the presence of C3 at the upper atmosphere of Titan, with a column density of 1013 cm-2. This study of Titan's atmosphere with very high-resolution visible spectroscopy presents a unique opportunity to observe a planetary target with a CH4-rich atmosphere, from which CH4 optical proprieties can be studied (9). It also showcases the use of a close planetary target to test new methods for chemical retrieval of minor atmospheric compounds, in preparation for upcoming studies of cold terrestrial exoplanet atmospheres (10).References: (1) Hörst S., 2017; J. Geophys. Res. Planets, doi:10.1002/2016JE005240; (2) Nixon C., et al, 2020; The Astronomical Journal, doi:10.3847/1538-603881/abb679; (3) Lombardo N., et al, 2019, The Astrophysical Journal Letters, 2019, doi:10.3847/2041- 658213/ab3860; (4) Rianço-Silva R., et al, 2023, submitted to Planetary and Space Sciences (under peer-review). (5) Hargreaves R., et al, 2020; The Astrophysical Journal Supplement Series, doi:10.3847/1538-4365/ab7a1a; (6) Hérbad E., et al, 2013; Astronomy & Astrophysics, doi:10.1051/0004-6361/201220686; (7) Dobrijevic M., et al, 2016; Icarus, doi.org/10.1016/- j.icarus.2015.12.045; (8) Schmidt M., et al, 2014; MNRAS, doi.org/10.1093/mnras/stu641; (9) Thompson M., et al, 2022; PNAS, doi.org/10.1073/pnas.2117933119; (10) Tinetti G., et al, 2018; Experimental Astronomy, doi:10.1007/s10686-018-9598-x
Upper mantle anisotropy under the strike-slip Dead Sea rift
Authors: Xu Huikai , Yu Youqiang , Xi Jiaji
Published: March 2024

Continental rifting is one of the fundamental tectonics of the Earth evolution while our current knowledge on the dynamic mechanism of the strike-slip ones are seriously limited. Here, a systematically shear-wave splitting investigation has been performed in the typical strike-slip Dead Sea rift to illuminate the upper mantle azimuthal anisotropic status across a transform boundary. Totally, 1855 well-defined anisotropic measurements are observed from 102 stations with dominantly N-S fast orientation, which is parallel to the rift strike but deviate from the absolute plate motion direction, mainly result from the plate-driven mantle flow deflected by the thick lithosphere of the eastern Arabian plate. Additionally, the significant fluctuation patterns of splitting times are identified on both the rift-parallel and rift-orthogonal profiles, among which the relatively large splitting times are generally concentrated at the rift zone and attributed to additional coupling lithospheric deformation from the shearing-oriented melt pockets. The consistent rift-parallel fast orientations, combined with the other geoscientific evidences, rule out the role of mantle plume or edge-driven convection in the rift development and further infer the Dead Sea rift to evolve in a passive mode.