bluuebunny/crossref_metadata_2025 huggingface dataset:
Ensemble Modeling of Atmospheric Pollutants: A Case Study with WRF-Chem and LOTOS-EUROS in Aburrá Valley, Colombia
Authors: Cruz-Ruiz Lisseth Milena , Fernández-Restrepo Fernando , Yarce-Botero Andrés , Solórzano-Araque Valeria , Quintero Olga Lucia
Published: March 2024

An evaluation of an ensemble of atmospheric Chemical Transport Models (CTMs) was carried out using WRF-Chemand LOTOS-EUROS over the Aburrá Valley, Colombia, an interesting region for huge density of population and mountainous topography. The models were configured in the same spatiotemporal domain and the pollutants of interest were nitrogen dioxide (NO2) and ozone (O3) due to their significant impact on sensitive ecosystems. The ensemble concentrations were assessed by comparing them to the data collected by local air quality monitoring stations against the simulated surface concentration. Additionally, vertical profiles were compared between each model and the ensemble. The Weather Research and Forecasting (WRF) is utilised as the Numerical Weather Model (NWM) driver in the two CTMs with identical initial and boundary conditions, to let the chemical operators from each model to be the contributors to the differences incorporated with an ensemble. The statistical comparison to assess the ensemble includes various metrics expressed in Taylor diagrams. These metrics comprise the mean factorial bias (MFB), root mean square (RMSE) error, and correlation factor (Corr) to evaluate the models and its ensemble against the measurements. The ensemble perspective of the Chemical Transport Model (CTM) diminishes the drawbacks of each CTM and enables us to comprehend the impact of key dynamics over rough topography that has a direct influence on the vertical transport of pollutants. The findings reveal which model aligns better with surface observations in the Aburra Valley and enable a qualitative identification of the principal dynamics in pollutant transport across this region utilizing two CTMs and their ensemble.
Roles of Tropical-Pacific Interannual–Interdecadal Variability in Forming the Super Long La Niña Events
Authors: Wang Run , Ren Hong-Li , Liu Minghong
Published: March 2024

The super long La Niña phenomenon, which has an extremely long duration, like the recent 2020–2023 La Niña event, is less concerned than the super El Niño. In this study, we identify five super long La Niña events after 1950 and investigate roles of the 2–3-year quasi-biennial (QB) and 3–7-year low-frequency (LF) ocean–atmosphere coupled processes of El Niño–Southern Oscillation (ENSO), and the interdecadal background in forming the basin-scale prolonged negative sea surface temperature anomalies (SSTAs) during these events. We group the five events into the thermocline-driven type (the 1983–1986 and 1998–2002 events) and the wind-driven type (the 1954–1957, 1973–1976, and 2020–2023 events). The former inherited a sufficiently discharged state of equatorial upper-ocean heat content from the preceding super El Niño and dominated by the thermocline feedback, leading to a LF oceanic dynamical adjustment to support the maintenance of negative ENSO SSTAs. The latter were promoted by the relatively more important zonal advective feedback and Ekman pumping feedback and deeply affected by a strongly negative equatorial zonal wind stress background state that sourced from the strong negative phase of the Interdecadal Pacific Oscillation. Besides, the QB ENSO variability with casual contributions during these events is less important. Results show that both the LF ENSO variability and the interdecadal Pacific background could assist to the genesis of such elongated La Niñas.
How THM Changes in Layered Geological Systems Influence Stability of Fractured Networks
Authors: Sidahmed Anas , Mcdermott Christopher
Published: March 2024

Various geo-energy applications such as geothermal energy, Carbon Capture and Storage (CCS) and underground heat storage are some of the technologies leveraged to realize Paris Agreement goals by cutting greenhouse gases emissions (GHG). However, these applications require in-depth understanding of the effect of coupled Thermal, Hydraulic, Mechanical and Chemical (THMC) processes that take place in the deep subsurface geological layers. This study focuses on the modeling of THM coupled processes in heterogeneous layered reservoirs.When geological heterogeneities exist in the subsurface, each layer will have its own thermal, geomechanical and geological properties such as thermal conductivity, thermal expansion coefficient, porosity, permeability, Young’s modulus, Poisson’s ratio and so on. These variations in the properties add more complexity to the behavior of coupled THM processes of the system, which in turn requires sophisticated modeling approaches. To reduce complexity, the subsurface layers can be bundled into groups called “geomechanical facies” based on the mentioned material properties from THM characteristics perspective.The work in this paper is based on key generic features of actual geo-energy applications where simulation modeling has been utilized to demonstrate how coupled THM processes are affected in heterogenous layers compared to homogenous layers. Hypothetical heterogenous layers have been divided into sets of distinct geomechanical facies. OpenGeoSys (OGS) open-source Finite Element based THMC code was utilized to build the run simulation models.The results demonstrate that variations in the rock thermal, hydraulic and mechanical properties among different neighboring layers have a significant and individually different impact on stress mapping and distributions in addition to strain transfer to the surface. Geomechanical stability of the system parts that are more prone to failure such as fractures and faults were assessed using Factor of Safety (FOS) analysis which are based on stress distribution and rock mechanical properties. Results suggest that geological heterogeneity has more significant impact on hard rocks compared to soft rocks. The latter (i.e., soft rocks) have the ability to maintain sealing capability of caprocks because they are more ductile and have more room for further deformation prior to failure.The simulation modeling results in this study contributes to the understanding of the key THM processes involved in heterogenous layered systems. Furthermore, this work provides valuable insights towards developing more generic design criteria and predictive models for various geo-energy applications which can be tailored and used in the design of the particular systems.
Synchronization patterns of heavy rainfalls between North India and the Sahel Zone on daily timescales
Authors: Strnad Felix , Hunt Kieran , Boers Niklas , Goswami Bedartha
Published: March 2024

The dominant drivers of boreal summer precipitation variance in tropical and subtropical regions are the Asian and the North African Summer Monsoon. Despite extensive investigation into regional precipitation dynamics, the interaction between these monsoon systems remains hardly understood.This study employs a complex climate network approach based on extreme rainfall events to uncover synchronously occurring heavy rainfall patterns. We identify a synchronization trend during the peak monsoon period in July, linking the rainfall in North India to that in the Sahel Zone.Our findings indicate that La Ni\~na-like conditions in combination with the Boreal Summer Intraseasonal Oscillation (BSISO) foster the synchronization. The convective clouds are subsequently transported by an intensified tropical easterly jet toward North Africa, introducing unusual convection over the Sahel region.
Quantifying long-term nutrient sources and pathways in the Ganges River basin
Authors: Elsayed Hamdy , Beusen Arthur , Bouwman Lex
Published: March 2024

The Ganges River basin is home to more than 600 million people. Intensive agriculture is widespread owing to the basin’s widespread fertile soils and abundant water availability. Together with urbanization and industrialization which have grown rapidly over the past decades across the basin, this has significantly impacted the river’s water quality with adverse impacts on human health and ecosystem. Elevated nutrient levels in the Ganges River, mainly from intensive agricultural practices and discharge of untreated wastewater, have led to surface and groundwater pollution across the basin. In this study, we employ the spatially explicit Integrated Model to Assess the Global Environment-Dynamic Global Nutrient (IMAGE-DGNM) to investigate nutrient sources and pathways and their fate in the Ganges river system. Basin-wide simulation results over the past five decades (1970-2020) will be presented and analysed along with discussions on the implication of nutrient pollution on the water quality of the Ganges River.
Signal Preservation in the Deepest Part of the EPICA Dome C Ice Core and Application to Palaeoclimate Reconstruction from 600,000 to 800,000 years ago
Authors: Klüssendorf Anna , Landais Amaëlle , Casado Mathieu , Teste Grégory , Prié Frédéric , Bouchet Marie , Harris Stuart Romilly
Published: March 2024

In the framework of the new ice core project Beyond EPICA an ice core is currently being drilled to provide a climate record extending over the past 1.5 million years. This ice core will cover the Mid-Pleistocene Transition (~1.2 − 0.8 million years before present) where the glacial-interglacial cycles shifted from following the obliquity to the eccentricity periodicity, as well as the Marine Isotope Stage 19 interglaciation which is considerably the best analogue for a natural Holocene climate regarding the orbital configuration. However, dating the old ice and the interpretation of the climate signal is hampered by extensive annual layer thinning at that depth, high basal temperatures close to melting point, and long residence time favouring diffusive exchanges leading to muted signals even if high-resolution data can be obtained. We are particularly concerned by the possible diffusion of the δ(O2/N2) and δ18O of O2 signals in the deepest part since these two parameters, measured in the air bubbles, are essential tools to provide dating of the deep part of the ice core. To investigate how these signals will be preserved in the bottom part of the ice core after diffusion, we present new high-resolution records of the elemental and isotopic composition of O2 and N2 from the deepest 200 m of the EPICA Dome C ice core spanning over the period from 600,000 to 800,000 years before present. We address the effect of diffusion by comparing the amplitude of the orbital scale variability of the δ(O2/N2) and δ18O of O2 signals in the deepest part of the EPICA Dome C ice core to the expected amplitude of these signals without diffusion and propose some perspectives for the analysis of the Beyond EPICA ice core.
Reconstructing the Greenland ice Sheet during the last two deglaciations
Authors: Eckert Majbritt Kristin , Lauritzen Mikkel , Rathmann Nicholas , Solgaard Anne , Hvidberg Christine
Published: March 2024

The Parallel Ice Sheet Model (PISM) is used to build up a glacial Greenland ice sheet, simulate the evolution of the Greenland ice sheet through glacial terminations I and II and investigate the evolution during previous warmer climates, the Eemian and the Holocene thermal maximum. During the Holocene, surface elevation changes derived from ice cores suggest a large thinning in the North, suggesting that the Greenland ice sheet was connected to the North American ice sheet in Canada during the last glacial. By including Canada in the modelling domain this thinning in the early Holocene as the connecting ice bridge broke up will be investigated. 
Groundwater storage variations in volcanic island aquifers using passive hydrogeophysical data: A feasibility study in Tenerife 
Authors: Gonzalez Pablo J. , González-Jiménez Miguel , Jones Mireia , Martín-Ariza Lucía , Boulesteix Thomas , Marrero Rayco , Charco María , Eff-Darwich Antonio
Published: March 2024

Groundwater in volcanic islands is usually one of the main sources of freshwater, and it is essential for sustainable development. In Tenerife Island, groundwater extraction occurs mainly by drilling horizontal water tunnels or “galleries”, as well as coastal wells on coastal aquifers systems. Since around 1900, but especially since the 60’s decade, hundreds of galleries and wells have been drilled, mainly for agriculture, industrial and freshwater supply. This has resulted in a sustained extraction of groundwater larger than the natural recharge, leading to a general groundwater table decline (locally up to 200+ m of drawdown). Since 2000, satellite radar interferometry (InSAR) applied to measure surface deformation has located several subsidence bowls in Tenerife. The localized surface deformation patterns have been correlated with water table changes and hence aquifer compaction. To investigate the effect of compaction processes on our ability to track groundwater storage variations of volcanic aquifers, we have set up a spatially dense passive hydro-geophysical monitoring network composed of geodetic and seismological instruments. The network has been running since summer 2023 and also enhances satellite radar interferometry estimates of ground deformation associated with the aquifer compaction processes. Here, we present preliminary results of the hydrogeophysical network after its first 9 months of operation (almost one hydrological year, July 2023-April 2024). As a first step towards understanding the dynamics of groundwater in this setting, we correlate the simultaneous observations of land subsidence rates and ambient seismic wavefield changes with respect to environmental variables (e.g., air temperature and proxy for soil moisture and soil temperature measurements as a function of depth). This experimental study will allow us to get close to improving the effectiveness of water management policies in aquifers in volcanic islands. Acknowledgements: We thank Spanish Agencia Estatal de Investigación projects PID2019-104571RA-I00 (COMPACT) funded by MCIN/AEI/10.13039/501100011033, and Proyecto PID2022-139159NB-I00 (Volca-Motion) funded by MCIN/AEI/10.13039/501100011033 and “FEDER Una manera de hacer Europa”. Thanks to the Teide National Park for the granted scientific permission to operate the geophysical network.
Assessing GFDL-ESM4.1 Climate Responses to CESM2-WACCM6 Geoengineering Forcing for 2.0°C Warming Target
Authors: Zhang Shipeng , Naik Vaishali , Paynter David , Tilmes Simone , John Jasmin
Published: March 2024

In this work we apply GFDL Earth System Model (GFDL-ESM4.1) to explore the climate responses to a geoengineering scenario that aims to restrict global warming to 2.0°C above pre-industrial levels (1850–1900) under the CMIP6 overshoot scenario (SSP534-OS) . Simulations of this geoengineering scenario with the CESM Whole Atmosphere Community Climate Model (CESM2-WACCM6) showed nearly unchanged interhemispheric and pole-to-Equator surface temperature gradients relative to present-day conditions around 2020, and reduced global impacts, such as heatwaves, sea ice melting, and large shifts in precipitation patterns (Tilmes et al 2020). Here we implement the identical stratospheric forcing in the GFDL-ESM4.1 model and find excessive global surface cooling and reduced precipitation responses, compared to those projected in CESM2-WACCM. Notably, the Southern Hemisphere experiences more substantial cooling compared to the Northern Hemisphere, accompanied by a north-ward shift in the Intertropical Convergence Zone (ITCZ). These distinct climate responses between GFDL-ESM4.1 and CESM2-WACCM6 can be traced back to their different climate feedback parameters. Furthermore, our analysis reveals that spatially heterogeneous forcing within the geoengineering scenario results in diverse climate feedback parameters even just in one model, through varying surface warming and cooling patterns. This research highlights the importance of considering model structure uncertainties and spatial forcing patterns for a comprehensive evaluation of future scenarios and geoengineering strategies.
Ocean-induced glacier retreat drives mass loss in Svalbard 
Authors: Li Tian , Heidler Konrad , Igneczi Adam , Hofer Stefan , Zhu Xiao Xiang , Bamber Jonathan
Published: March 2024

Arctic Amplification is making Svalbard one of the most climatically sensitive regions in the world and it has been undergoing accelerated mass loss over the past several decades. A major uncertainty in predicting the future sea-level rise contribution from marine-terminating glaciers is ice dynamics, which can be driven by non-linear calving processes. However, the relationship between calving and ice dynamics is not well understood in Svalbard, in part due to the lack of high-resolution calving front observations. To improve our understanding of the glacier calving dynamics and its relation to dynamic mass loss, here we use a novel fully automated deep learning framework to produce a new calving front dataset of 149 marine-terminating glaciers in Svalbard. This dataset, which includes 124919 glacier calving front positions from 1985 to 2023, has high spatial and temporal resolutions and is derived from multiple optical and SAR satellite images. We then use this new calving front dataset to systematically quantify the calving front change variabilities at different temporal scales, and identify the key climate drivers controlling the calving dynamics. We show that ocean forcing plays a central role in controlling the glacier calving front changes and mass imbalance. Our study highlights the importance of including ice-ocean interaction in projecting future glacier mass loss from Svalbard.  
The Impact of Tree Species and Charcoal on Soil Fauna in Post-Fire Forest Ecosystems
Authors: Tran Thi Hong Van , Józefowska Agnieszka , Woś Bartłomiej , Pietrzykowski Marcin , Wanic Tomasz , Schmelz Rüdiger M. , Frouz Jan
Published: March 2024

Soil fauna, particularly enchytraeids and earthworms, play a crucial role as soil engineers, actively contributing to nutrient cycling through the breakdown and ingestion of litter material. These organisms engage in intricate interactions with microorganisms responsible for decomposing and mineralizing detritus. The present study seeks to delve into the complex interplay among tree species, charcoal presence, and soil fauna within post-fire forest ecosystems. The investigation took place in Rudziniec, Poland, a site that witnessed one of Europe's largest fires in 1992. Two delineated areas were observed: one with post-fire charcoal presence and another with removed charcoal. Four distinct tree species—pine (Pinus sylvestris L.), larch (Larix decidua Mill.), birch (Betula pendula Roth), and oak (Quercus robur L.)—were selected as representative species for the study. Samples were obtained from locations adjacent to the trees at a depth of 0-10 cm for echytraeids and at a depth of 0-25 cm for earthworms. The study elucidates the impacts of post-fire charcoal removal or retention on soil fauna across diverse tree species. When considering the various tree species, enchytraeid density was higher in coniferous trees (pine and larch) compared to deciduous trees (birch and oak). Among these, oak trees exhibited the highest enchytraeid species diversity, yet their density was lowest (60944 ind.m-2). Among experimental plots, in birch plots with post-fire charcoal retention, enchytraeid density was lowest (27470 ind.m-2); conversely, in charcoal removal plots, it showed the highest number with 105355 ind.m-2. Regarding earthworm biodiversity, a maximum of two species were observed across all plots. Earthworm density was lower in coniferous trees (12.65 ind.m-2 in pine and 10.67 ind.m-2 in larch) compared to deciduous trees (20.09 ind.m-2 in birch and 14.67 ind.m-2 in oak). With charcoal presence, earthworm density sharply decreased in coniferous trees while increasing in deciduous trees. A similar trend was observed in earthworm biomass. Among all experimental plots, the highest biomass value was found in pine trees with charcoal removal (4.54 g.m-2) whereas the lowest value with charcoal presence (0.35 g.m-2). These differences suggest an intricate relationship between post-fire charcoal management, tree species, and their consequential impact on soil fauna. The insights gathered from this study hold valuable implications for informing ecosystem management and restoration strategies, contributing to a more comprehensive understanding of the intricate dynamics within post-fire environments.This research was funded by The National Science Centre, Poland, grant No. 2021/42/E/ST10/00248. The analyses were performed in the Laboratory of Forest Environment Geochemistry and Reclaimed Areas, University of Agriculture in Krakow.
Identification of groundwater recharge zones using comparative analysis of drainage networks
Authors: Das Sourav Sundar , Saraf Arun Kumar , Goswami Ajanta
Published: March 2024

Groundwater, being limited extent in hardrock terrain is undeniably a precious resource for livelihood. In the hardrock terrain of Bundelkhand, India where seasonal rainfall is mostly discharged through surface runoff, it is necessary to check and delay the surface runoff to mitigate water table decline caused due to overgrowing demand for groundwater as to drinking and irrigation purposes. The objective of this study is to identify suitable places for groundwater recharge where the process of recharge to the groundwater offers optimum results as per the prevailing hydrogeological conditions. This objective has been achieved by remote sensing and GIS based techniques using DEM and toposheet of the Narain watershed of the Bundelkhand region. In this present study a comparative analysis has been carried out by superimposing drainage network extracted from the toposheet over simulated drainage network derived from the DEM to visualise the clustering tendency of the two data sets. The comparative analysis reveals a mismatch of the two datasets at some places having randomness number less than 1 indicating potential groundwater recharge zones. Such mismatch has appeared at places where the degree of infiltration is significant enough to divert the course of the existing drainage network from the simulated one because of the assumption of the surface to be insulated. This study proves to be a quick reliable method for the identification of groundwater recharge zones for hard rock terrain.
Accuracy of the Scalar Magnetometer aboard ESA's JUICE Mission
Authors: Amtmann Christoph , Pollinger Andreas , Ellmeier Michaela , Dougherty Michele , Brown Patrick , Lammegger Roland , Betzler Alexander , Agú Martín , Hagen Christian , Jernej Irmgard , Wilfinger Josef , Baughen Richard , Strickland Alex , Magnes Werner
Published: March 2024

The presentation discusses the accuracy of the scalar Coupled Dark State Magnetometer on board the Jupiter Icy Moon Explorer (JUICE) mission of the European Space Agency. The scalar magnetometer MAGSCA is part of the J-MAG instrument.MAGSCA is an optical, omni-directional scalar magnetometer based on coherent population trapping, a quantum interference effect, within the hyperfine manifold of the 87Rb D1 line. The measurement principle is only based on natural constants and therefore, it is in principle drift free and no calibration is required. However, the technical realisation can influence the measurement accuracy.The most dominating effects are heading characteristics, which are deviations of the magnetic field strength measurements from the ambient magnetic field strength.The verification of the accuracy and precision of the instrument is required to ensure its compliance with the performance requirement of the mission: 0.2 nT (1-σ).The verification is carried out with four dedicated sensor orientations in a Merritt coil system, which is located in the geomagnetic Conrad observatory. The coil system is used to compensate the Earth’s magnetic field and to apply appropriate test fields to the sensor. A novel method is presented which separates the heading characteristics of the instrument from residual (offset) fields within the coil system by fitting a mathematical model to the measured data. It allows verifying that the MAGSCA sensor unit does not have a measurable remanent magnetisation as well as that the desired accuracy of 0.2 nT (1-σ) is achieved by the MAGSCA flight hardware for the JUICE Mission.
The International Association of Geodesy
Authors: Gross Richard
Published: March 2024

2024 marks the 162nd anniversary of the founding of the International Association of Geodesy. In 1862, 15 States agreed to cooperate in a "Central European Arc Measurement" project to observe the shape of the Earth. Besides leading to an improved knowledge of the shape of the Earth, the measurements taken during this project also led to an improved reference frame and geoid for Central Europe. In the course of taking these measurements scientific issues were encountered that also had to be addressed. The spirit of cooperation in both taking operational measurements and conducting scientific research that exists today within the IAG has been a hallmark of the IAG ever since it was founded in 1862. The dual nature of the IAG, in advancing both observations and science, is reflected in the organizational structure of the IAG. Services are responsible for advancing geodetic observations in their area of expertise; Commissions and Inter-commission Committees are responsible for advancing geodetic science; Projects are incubators for new initiatives; the Communications and Outreach Branch, together with GGOS, is responsible for promoting geodesy to the other sciences and to society at large; and GGOS, the Global Geodetic Observing System, is meant to integrate the diverse geodetic observations into a coherent geodetic imaging system of the Earth as a whole. One of the strengths of geodesy is its interdisciplinary nature. Geodetic observations contribute to improving our understanding of many different Earth processes, from space weather to core dynamics. This affords the opportunity for geodesists to collaborate with scientists from many different disciplines. Besides the value to science, geodetic data and products are also of great value to society. The International Terrestrial Reference Frame (ITRF) provided by the International Earth Rotation and Reference Systems Service (IERS), one of the 12 Services of the IAG, underpins location-based services like navigation aids on cell phones. By forging collaborations with other organizations, the IAG can ensure that its data and products continue to meet the needs of both its scientific and societal customers.
Study of VLF phase and amplitude variations before the Turkey Syria Mw 7.8 EQs
Authors: Boudjada Mohammed  Y. , Biagi Pier Francesco , Eichelberger Hans Ulrich , Galopeau Patrick H.M. , Schwingenschuh Konrad , Solovieva Maria , Nico Giovanni , Lammer Helmut , Voller Wolfgang , Stachel Manfred
Published: March 2024

We investigate the recent earthquakes (EQs) that occurred on 06 February 2023 principally in the central southern part of Turkey and north western of Syria. The tectonic plate movements between Anatolian, Arabian and African plates are well known to be subject to EQs. The coordinate of the epicenter was 37.08°E and 37.17°N with depth in the order of 10 km and a magnitude Mw7.8. Beside aftershocks, a few hours later a strong Mw7.7 earthquake occurred in the same region . We consider in this analysis the Bafa VLF transmitter (TBB) signal emitting at frequency of 26.7 kHz and localized in the Anatolia region (Turkey) at longitude of 27.31°E and latitude of 37.40°N. TBB transmitter signal is daily monitored by the VLF Graz facility (Biagi et al., 2019; Galopeau et al., 2023) with a sufficient signal to noise ratio principally during night observations. We study the variations of the phase and amplitude of TBB signals, as detected by Graz facility (15.43°E, 47.06°N) few weeks before the earthquakes occurrence. It is essential to note that the geographical latitudes of the epicenter and the TBB transmitter are about 37°N, and the distance, in the order of 850 km, is found smaller than the radius of the earthquake preparation zone, as derived from Dobrovolsky et al. (1979), when considering the magnitude of the seismic event, i.e. Mw7.8. We have applied the terminator time (TT) method to make evident the presence of sunrise and sunset time shifts at terminators one week to ten days before EQs.  We discuss essentially the anomalies, in the phase and the amplitude of TBB transmitter, which are probably linked to the electron density variations at the formation and the destruction of the ionospheric D-E-layers. References:Biagi et al., The INFREP Network: Present Situation and Recent Results, Open J. Earth. Research, 8, 2019.Dobrovolsky et al., Estimation of the size of earthquake preparation zones, Pageoph, 117, 1979.Galopeau et al., A VLF/LF facility network for preseismic electromagnetic investigations, Geosci. Instrum. Method. Data Syst., 12, 2023.
Navigating Nature and Climate Risks: An Integrated Framework for Economic Assessment
Authors: Stevanovic Miodrag , von Jeetze Patrick José , Johnson Justin Andrew , Ceglar Andrej , Popp Alexander
Published: March 2024

Biodiversity loss and ecosystem degradation could pose a substantial threat to financial stability and the wider economy. Despite scientific evidence of the ongoing ecosystem degradation, methodological and data challenges have so far prevented a detailed assessment of the economic and financial risks.  While progress has been made in assessing climate change related risks, our understanding of the linkages between the economy and ecosystem service degradation is still limited. Here we pioneer a nuanced approach to understanding the emerging financial risks of ecosystem change.  Using the LPLmL-MAgPIE-SEALS modeling framework, we assess physical, transition and financial risks considering feedbacks from climate change, land use, and degrading ecosystem services. Focusing mainly on the EU, we also assess interconnectedness with other global regions where loss of ecosystem services is more pervasive. Our framework includes climate-sensitive spatially explicitly biophysical data within a partial equilibrium land-system model. Modelled land-use patterns are downscaled to derive fine-scale changes in ecosystem service supply and associated economic feedbacks. We assess various scenarios that build on the existing NGFS (Network for Greening the Financial System) framework. These scenarios range from a degraded world without policy interventions, to an integrated climate-nature scenario, with ambitious policies to mitigate both climate and ecosystem service change. The results indicate diverging biodiversity response based on varying climate and nature policy ambition, emphasizing the need to extend biodiversity safeguarding beyond exclusive reliance on climate mitigation policies. Financial risks are assessed through an analysis of sectoral dependencies on various ecosystem services, laying out the basis for a comprehensive framework that supports informed decision-making facing emerging climate and nature-related risks.
Exploring Noise-induced and CO2-driven AMOC collapses in the PlaSIM-LSG climate model with a Rare Event Algorithm.
Authors: Cini Matteo , Zappa Giuseppe , Ragone Francesco , Corti Susanna
Published: March 2024

Earth-system Models of Intermediate Complexity (EMICs) are climate models featuring a simplified representation of climate processes and a much lower computation cost. This makes them particularly suitable for exploring phenomena with a large ensemble simulation approach. Here we use the coupled atmosphere-ocean PlaSIM-LSG EMIC to study the possibility of Atlantic Meridional Overturning Circulation (AMOC) spontaneous collapses and how this is altered in the presence of external anthropogenic forcing. Understanding the stability of the AMOC and its response to anthropogenic forcing is of key importance for advancing climate science. The idea of a “safe-operating space” has been proposed in order to define a threshold on anthropogenic forcing within which the AMOC does not lose stability. This requires understanding the combined action of CO2-driven and noise-induced processes in climate tipping events First, we address the occurrence of noise-induced AMOC collapses, i.e. spontaneous abrupt weakening  events induced by chaotic internal climate variability in absence of any external forcing. We address the problem of finding these extreme events via the application of a Rare Event Algorithm, which - via a selective cloning of the most interesting model trajectories -  allows a faster exploration of the model phase space in the direction of an AMOC decrease. The algorithm is applied to a PlaSIM-LSG ensemble simulation run at T21 spectral resolution in the atmosphere, and 3.5 degrees in the ocean, with fixed pre-industrial conditions. A number of collapse events, unseen in the pre-industrial control run, are sampled by the algorithm. Looking at the mechanisms causing the AMOC spontaneous collapse, we find that zonal wind stress over the North Atlantic is the main driver of the initial AMOC slowdown, while the suppression of surface convection in the Labrador sea is the likely cause of the subsequent AMOC collapse. Then, we investigate the influence of increasing CO2 levels on the frequency of these spontaneous AMOC collapses. We show that a higher CO2 not only leads to the well-known weakening of the AMOC mean state, but it also increases the possibility of incurring in abrupt noise-induced transitions. The employment of EMICs, combined with the proposed approach, samples a large number of rare phenomena. This procedure allows us to explore statistical properties that are not accessible with a deterministic approach in state-of-the-art high resolution models.
Spatial downscaling of climate projections of temperature and precipitation over complex mountain terrain: A case study in the north-eastern Italian Alps
Authors: Matiu Michael , Napoli Anna , Zardi Dino , Bellin Alberto , Majone Bruno
Published: March 2024

Mountain regions are particularly sensitive to climatic change. In these areas the complex topography modulates meteorological and climatic patterns with the elevation playing the strongest influence on temperature and precipitation. However, most regional climate models used in climate change assessments are too coarse to capture the relevant elevation gradients for impact studies, such as in hydrology, which require detailed spatial information on water availability, either in liquid or in solid state.Focusing as a case study on Trentino-Alto Adige region in the north-eastern Italian Alps, we compare several statistical approaches for downscaling regional climate models to the spatial scale needed for impact studies in mountain areas. In particular, we propose a comparison between a novel method, based solely on climate model output using generalized additive models (GAM), and quantile mapping (QM) methods using an interpolated observational dataset as reference. We then evaluate and discuss the effectiveness of  downscaling approaches, relying on both spatial and temporal metrics and taking into account the possible elevation dependency.Preliminary results show that the approach using GAMs offers spatial fields consistent with the large-scale climate model, while the QM methods have artificial breaks at grid cell boundaries. On the other hand, the GAM approach inherits the biases from the climate model, while QM also simultaneously performs bias adjustment using the observational dataset.
In Situ Observations of Interaction Between the Closed Magnetic Field of Earth’s Transpolar Auroral Arcs and the Interplanetary Magnetic Field
Authors: Kaweeyanun Nawapat , Fear Robert
Published: March 2024

Transpolar arcs (TPAs) are extensions of auroral emission poleward beyond the main ovals, forming partial or complete bisections known as ‘theta’ auroras. A prominent hypothesis suggests that a TPA occurs through stagnation of magneto-plasma returning from Earth’s magnetotail under northward interplanetary magnetic field (IMF), resulting in a ‘wedge’ of closed magnetic field lines in the open polar cap on which particles resemble those in the nightside equatorial plasma sheet. It has been proposed that a TPA’s closed-field lines may reach sufficiently high latitude to magnetically reconnect with the IMF at the lobe magnetopause, leading to observed coincidence of the TPA and a cusp spot. Using conjugate data from Cluster, Imager for Magnetopause-to-Aurora Global Exploration (IMAGE), Special Sensor Ultraviolet Spectrographic Imager (SSUSI), and other instruments, we demonstrate at least one case study of potential first in situ detection of TPA-IMF magnetic reconnection with magneto-plasma and visual aurora evidence, and several further instances of particles on closed magnetic field lines near the lobe magnetopause. Pending affirmative analysis, the existence of TPA-IMF reconnection events will not only further support the ‘wedge’ TPA formation hypothesis, but also indicate that lobe reconnection can open topologically closed nightside magnetic field lines, introducing new polar cap dynamics under northward IMF.
Does auroral proton precipitation affect the temperature and chemistry of excited OH in the Svalbard mesopause?
Authors: Dayton-Oxland Rowan , Whiter Daniel
Published: March 2024

Energetic proton precipitation causes proton aurora over Svalbard, but its effects on the chemistry and heat economy of the atmosphere are not well observed. Temperature and intensity changes in the OH layer have been observed during auroral electron precipitation (Suzuki et al., 2018), but no studies have yet investigated the effect of auroral proton precipitation. This study will use observations made by the HiTIES (High-Throughput Imaging Echelle Spectrograph) instrument located at the Kjell Henriksen Observatory near Longyearbyen, Svalbard. This spectrograph observes proton precipitation in the H-alpha wavelength as well as the OH*(8-3), (9-4), (5-1) airglow vibrotational bands. These OH bands are temperature and species density dependent which can be compared to the H-alpha profile and luminosity as a measure of proton aurora energy and flux. In addition, the vibrotational states above and below v'=6 result from different production processes which can be studied. Prelimiary results will be presented. 
Improved alternative GRACE-FO accelerometer transplant product computed at Graz University of Technology (TUG)
Authors: Öhlinger Felix , Mayer-Gürr Torsten
Published: March 2024

Gravity field recovery using GRACE-FO observations requires the reduction of non-conservative forces usually measured by the onboard accelerometer in the center of mass of each spacecraft. The accelerometer of GRACE-D degraded significantly in June 2018 showing increased noise levels by orders of magnitude and common mode errors on all acceleration components. However, the quality of the accelerometer measurements is vital for accurately estimating the Earth’s gravity field. The standard approach to account for the degraded data of GRACE-D is to replace the measurements with synthetic data, the so-called transplant data. At Graz University of Technology (TUG) a very effective procedure to estimate such an accelerometer transplant was developed adopting a remove-restore approach (Behzadpour, 2021). Hereby, data from GRACE-C and non-conservative force models are used to substitute GRACE-D data. Since then the effort was made to further improve the TUG transplant product.Effects that need to be considered are on the one hand the increased solar activity as we are approaching the peak of solar cycle 25 which makes it harder to estimate an accurate transplant product by using force models and on the other hand influences such as thruster leakage which occurs on both GRACE-C and GRACE-D. Investigations that were carried out comprise the adaption of the physical properties of the satellite’s surface elements and the consideration of bias jumps at each thruster firing. The bias jumps for GRACE-C were corrected before the transplant process and with the use of actual GRACE-D data thruster leakage and some residual drag acceleration was restored for GRACE-D.
Idealized, High Resolution, 3D Modelling of Ice-Sheet Ocean interactions in long and narrow fjords
Authors: Wiskandt Jonathan , Koszalka Inga Monika , Nilsson Johan
Published: March 2024

Ocean forcing of basal melt at the Greenland and Antarctic ice sheets remains a major source of uncertainty in climate ice sheet modelling. Previous efforts to represent these effects focused mainly on the properties of the ocean waters reaching the marine terminating glaciers as well as the near-ice boundary layer flows and processes at the ice-ocean interface. We use high resolution, three dimensional modelling to show the influence that rotational effects have on the fjords circulation and the melt rate distribution and compare the total melt to earlier estimates from two dimensional simulations. Furthermore we investigate the influence that the along and across fjord bathymetry of Greenlandic glacial fjords has on the exchange flow of the warm ocean waters towards the ice sheets and the glacially modified water toward the open ocean. We find that the circulation pattern produced by rotational effects has a profound effect on the distribution of the melt rate at the ice base, producing a concentrated outflow and a melt maximum at the eastern side of a fjord that opens to the open ocean in the north even in narrow fjords (width of the order of the local Rossby Radius). The bathymetry in the fjord has a restricting effect on the inflow of warm Atlantic water and hence on the temperature forcing at the ice base. We compare the inflow strengths for different fjord bathymetries to theoretical estimateion using hydraulic theory (Whitehead, 1998).
Assessing Job Wrapping as an Strategy for Workflow Optimization on Shared HPC Platforms
Authors: Giménez de Castro Marciani Manuel , Utrera Gladys , Castrillo Miguel , Acosta Mario C.
Published: March 2024

Experimenting with modern ESM inherently requires a workflow organization to handle the multiple steps comprising of, but not limited to, execution, data governance, cleaning, and coordinating multiple machines. And for climate experiments, due to long scale of the simulations, workflows are even more critical. The community has thoroughly proposed enhancements for reducing the runtime of the models, but long has overlooked the time to response, which also takes into account the queue time. And, that is what we aim to optimize by wrapping jobs, which would otherwise be submitted individually, onto a single one. The intricate three-way interaction of the HPC system usage, scheduler policy, and user's past usage is the main challenge addressed here to analyze the impact of wrapping jobs.
Interaction Between Large Wood and Sediment Transport in an Alpine Torrent in the Dolomites
Authors: Martini Marco , Bettella Francesco , D'Agostino Vincenzo
Published: March 2024

Large wood (LW), defined as woody pieces exceeding 1 m in length and 10 cm in diameter, significantly shapes channel morphology and ecological habitats within Alpine torrents. Lower-order alpine torrents, with their smaller drainage areas and steeper gradients, are particularly sensitive to LW dynamics. The movement of LW greatly affects channel processes, altering flow patterns and sediment dynamics. LW can retain sediments and form log steps that may reduce bed erosion. Moreover, the accumulation of LW at bridge piers and filters or openings of retention check dams can exacerbate flood hazards, emphasizing the crucial need for its accurate quantification for more effective hazard assessments and protection measure design. Our investigation aims to assess changes in the LW budget in the Ru de Vallaccia catchment (covering 1.72 km2, Melton number 0.97, mean channel slope 45%) in the province of Belluno, Veneto, Italy. Specifically, we explore variations in LW volume before and after a heavy rainstorm event with a return period between 2 and 5 years that occurred between the 30th of October and the 2nd of November 2023. Furthermore, this study examines the correlation between segments of the channel affected by sediment erosion and deposition and changes in both the spatial distribution and volume of LW within the channel. Field surveys coupled with high-resolution topography (HRT) assessments conducted before and after the rainstorm event (July and November 2023) allow for a comprehensive evaluation of sediment and LW budgets. Our methodology involves direct field measurements of LW and photointerpretation using GIS software on orthophotomosaics resulting from HRT surveys. Additionally, we utilize the Digital Elevation Model (DEM) obtained from HRT surveys to analyze channel geomorphological changes through the DEM of Differences (DoD) technique, enabling precise quantification and visualization of sediment alterations related to erosion and deposition phenomena. Preliminary findings reveal pronounced sediment mobility, significant alterations in channel morphology, and notable changes in both the spatial distribution and volume of LW. The results of the study highlight the close link between patterns of erosional or depositional sediment dynamics and alterations in the LW budget, elucidating the intricate interaction between geomorphic processes and the presence and evolution of LW during subsequent flood events in steep mountain basins. In addition, these insights have substantial implications for addressing or guiding periodic monitoring of LW and thereby improving our hazard mitigation strategies against those sediment transport events (bedload, debris flood, and debris flow) capable of encompassing significant amounts of LW.
Development of a mathematical model for the determination of the atmospheric boundary layer height using artificial intelligence
Authors: Estrada Sebastián , Quintero Montoya Olga Lucia
Published: March 2024

The Atmospheric Boundary Layer Height (ABLH) is a fundamental parameter for many meteorological applications and climate change assessment and evaluation. A large number of methods for ABLH determination have been proposed; however, there is no sufficiently reliable and feasible method for this purpose. The rise of intelligence-based mathematical models for feature determination in data space has allowed their application to solve problems similar to ABLH determination. This article describes the development of a mathematical model based on artificial intelligence for ABLH determination, in which an introductory analysis of the data space from the point of view of machine learning, unsupervised, and supervised methods is presented. The methods explored are the mountain method, subtractive clustering, and the classic K-means and its soft counterpart, Fuzzy C-means. Furthermore, an analysis was conducted to determine which similarity function—whether Euclidean, Manhattan, Mahalanobis, or Cosine—best fits for ABLH estimation in each unsupervised method. For classification in a supervised fashion, the best suitable models, among others, are support vector machines and decision trees. Different internal metrics (Silhouette Index, Calinski-Harabasz score) and external metrics (root mean square error and adjusted Rand score), with a reference made by means of visual inspection by an expert, were used to evaluate the methods. The unsupervised mountain method with the Manhattan similarity function proved to be the most feasible, as it is a non-stochastic method, its computation time is reduced, and it does not require an ABLH reference. The data used was extracted from several sources: 83 days of quasi-continuous LIDAR data with 23,000 data points located at Brest, France, measured with a MiniMPL from the Meteo France LIDAR network, were used. An ABLH reference from a radiosonde adjacent to the site of the LIDAR system was used. The references range from October to December 2018. The root mean square error achieved for the whole dataset was 600 m for the mountain method. The presented method is shown to be effective for various atmospheric situations, regardless of their complexity.