bluuebunny/crossref_metadata_2025 huggingface dataset:
A comparative study of mineral-melt interactions at Kane Megamullion and Atlantis Massif: Identifying universal processes building the slow-spreading lithosphere
Authors: Boulanger Marine , Godard Marguerite , Ildefonse Benoit , Bakouche Malissa
Published: March 2024

The structure of the lithosphere and the associated magmatic systems found in different locations along slow-spreading ridges can vary dramatically, from melt-starved to magmatically robust segments. A growing number of studies suggest that the evolution of the magmatic crust being governed solely by fractional crystallization is too simplistic. Reactions between migrating melts and their surroundings play a key role during accretion, yet the full extent of their impact is still to be resolved. We present here the results of a petrological, microstructural, and in situ geochemical study of two drilled magmatic sequences from the Kane Megamullion and Atlantis Massif oceanic core complexes. Our results show that mineral-melt interactions generate locally strong textural and/or geochemical heterogeneity at the cm-scale, but their impact can also be reconstructed at the 100m-scale. We found evidence for assimilation at various degrees of primitive lithologies of potential mantle origin within gabbros (sensu lato) at both locations, in addition to typical melt-mush reactions previously described in other slow-spread magmatic systems. Numerical modeling shows the sameness of the reaction equations to be considered for both sequences. Yet, the regime of the reactions (ranges of assimilation over crystallization ratios) varies between Kane Megamullion and Atlantis Massif, variations which likely result from differences in melt fractions present during mineral-melt interactions. We infer, relying on our observations, available thermodynamic modeling, and previous studies, that the regime of the reactions is most likely controlled by the melt flux during the formation of the two sections.
Submarine Geomorphology and Seafloor Instabilities Revealed from Geophysical Data Offshore Southeastern Taiwan
Authors: Chen Liwen , Han Wei-Chung
Published: March 2024

Taiwan has excellent natural conditions for marine energy development. However, due to the active marine environment and geological processes, submarine geohazards must be carefully assessed before engineering development offshore southeastern Taiwan. Tectonically, it is situated in the oblique collision between the Eurasian Plate and the Philippine Sea Plate with fast exhumation and eroding transportation of sediments. Previous studies suggest that the Southern Longitudinal Trough (SLT) is characterized by a series of backthrusts and slumpings. Considering the rapid erosion and deposition led by extreme events, including typhoons and active tectonics, offshore SE Taiwan is an excellent site to study submarine geomorphology and seafloor instabilities.After detailed structural and morphological analyses from seismic and bathymetry data, some geological features, faultings, gullies, and submarine canyon systems are recognized, moreover, several sliding scars and slumpings are interpreted from repeated and sequence surveys. It gives us insights into the potential mechanisms of sediment transportation and geological hazards by discussing the structure connections and distribution.Since the study area has high ocean energy potential, appropriate site selection and development planning based on geological analysis should be carried out before marine industry projects. Whether in marine scientific research, site selection, engineering design, or social and economic development, studying geological processes and seabed stability offshore SE of Taiwan is urgent. Our results could provide a basis for subsequent seabed monitoring and engineering development.
Modeling in-situ desiccation cracks in a ventilated niche using homogeneously and randomly distributed material parameters
Authors: Cajuhi Tuanny , Ziefle Gesa , Maßmann Jobst , Nagel Thomas , Yoshioka Keita
Published: March 2024

Assessing barrier integrity under varying environmental conditions is crucial in the context of radioactive waste disposal. This study, originally  conducted at the Mont Terri Rock Laboratory in Switzerland within the Cyclic Deformation (CD-A) experiment, gains new understanding in this context. The laboratory, located within an Opalinus Clay formation, has been also instrumented to observe the triggers of desiccation cracking in open and closed excavations. Seasonal changes play an important role especially during winter where the relative air humidity reduces and drives desiccation cracking. To model this dynamic, we employed a hydro-mechanical model incorporating macroscopic poromechanics, the Richards equation for partial saturation and the phase-field modeling approach for cracking. Key to our study was the evaluation of unsaturated hydro-mechanical responses using field-acquired parameters such as the measured crack apertures, supplemented by existing literature. We established a good correlation between the observed and calculated crack formation by using the measured seasonal changes in relative air humidity as boundary condition as well as using  homogeneously and randomly distributed material parameters [1]. Furthermore, our study delves into the implications of enhanced permeability due to cracking on barrier integrity. Our findings offer insights into the dynamics of crack development and their implications, thereby making an  incremental contribution to the broader goal of ensuring safe and effective management of radioactive waste disposal.[1] T. Cajuhi, G. Ziefle, J. Maßmann, T. Nagel and K. Yoshioka, Modeling desiccation cracks in Opalinus Clay at field scale with the phase-field approach. InterPore Journal (in press).
Climate and Weather Information Services for better governance and risk reduction of wildfires in North Western Europe
Authors: Lambrechts Hugo , Stoof Cathelijne , Kroeze Carolien , Ludwig Fulco , Papa Spyros
Published: March 2024

Wildfires are an emerging risk in NW Europe, primarily due to increasingly conducive weather conditions resulting from climate change. This work examines the vital role of climate adaptation services to contribute to knowledge sharing and network building among professional stakeholders on a national level and within the region. Based on online survey responses from land managers/owners, forest managers/owners, fire services, and governments, we explore the intricacies of wildfire risk perception and the necessity of tailored climate and weather information for effective wildfire governance.Our research investigates how climate information services can bolster wildfire risk reduction, emphasizing the development of these services as a knowledge-sharing and network-building approach. We explore how tailored, locally relevant solutions and a thorough process of knowledge exchange and learning can build networks, ultimately delivering actionable knowledge that fosters an awareness culture among stakeholders.The work delves into the current perception and awareness of wildfire risks among professional stakeholders. We examined their risk awareness, preparedness, and responsibility perceptions, questioning whether experience with wildfires correlates with higher awareness or if stakeholders outside civil protection have lower preparedness perceptions. Additionally, we investigated the specific information stakeholders utilize for wildfire risk reduction, discerning whether weather, climate, or risk reduction information is more beneficial. This exploration includes an analysis of how this information correlates with preparedness, awareness, and responsibility perceptions and whether discrepancies exist between the use and needs of stakeholders.Preliminary result indicate that the development of a wildfire weather annd climate infomration service may contribute to wildfire governance and risk reduction in North Western Europe. Currently there is high awareness among most wildfire professionals, but that stakeholders do not feel prepared for future wildfire conditions. More than half of the respondents didn't know about the Copernicus EFFIS wildfire services, indicating that marketing and usibility of these products need to be increased. Stakeholders prioritised short-term weather forecasts and risk reduction information above other information.In conclusion, we argue for the strategic use of climate information services as a means of enhancing the governance of wildfires in NW Europe. By identifying the climate and weather information needs of professionals and examining their perceptions and awareness of wildfire risks, we aim to contribute to the development of more effective, informed strategies for wildfire prevention and management in the face of changing climatic conditions.
Seasonal changes in photosynthesis, respiration and NEE of a reclaimed post-mining site at the early stage of succession
Authors: Badraghi Aysan , Kučera Jiří , Frouz Jan
Published: March 2024

No investigations have addressed the CO2 fluxes, including NEE (Net Ecosystem Exchange), GEE (Gross Ecosystem Exchange), and ER (Ecosystem Respiration), in extremely disturbed areas like post-mining sites. Despite its importance, there is a big gap in the existing research literature regarding these specific ecosystems. Therefore, to determine the carbon sequestration and emission potential of a restored early post-mining stage, this study was conducted in the northwestern Czech Republic during 2023.To achieve this objective, continuous measurement of NEE was conducted using an Eddy Covariance (EC) tower from January to October 2023. The site was leveled in 2019 and planted with 1-yr-old alder (Alnus glutinosa) seedlings at a density of 10000 seedlings/ha-1. The high-frequency raw data (10 Hz) was processed using Eddypro software (LICOR, Lincoln, NE, USA) to calculate 30-minute average fluxes of CO2. More processing on the 30-minute data involved quality checks, despiking, u* filtering, gap filling, estimation of uncertainty in the gap-filled half-hourly data, and the partitioning of NEE into GEE and ER.Four years after reclamation, ER (1.10 kg C m-2) exceeded carbon assimilation (GEE = -0.85 kg C m-2), however, the resulted NEE was near zero (0.25 kg C m-2) for the entire 10-month period. The greatest losses of CO2 into the atmosphere occurred during the summer (July – October), with an average daily value of 4.37 ± 1.19 g C m-2. Meanwhile, spring with the highest rate of assimilation (April – June; average daily value of GEE -4.35 ± 0.39 g C m-2), acted as a net sink of CO2, with an average daily value of -0.24 ± 1.16 g C m-2. This finding implies a high assimilation capacity of the restored post-mining site at the early stage of succession. Overall, based on our analysis, temperature and vapour pressure deficit (VPD) were identified as the main driving factor for NEE and ER, while global radiation (Rg) and temperature were found to be the most important factors for GEE.
Sea-ice lead dynamics in the Arctic Ocean and associated drivers
Authors: Willmes Sascha , Heinemann Günther , Rasic Michelle
Published: March 2024

Based on a novel sea-ice lead climatology derived from thermal-infrared satellite imagery we identify drivers of wintertime sea-ice dynamics in the Arctic Ocean. ERA-5 atmospheric reanalyses and large-scale sea-ice drift data are used to investigate the causes for prominent spatial patterns and for the inter-annual variability in the occurrence of sea-ice leads. We can show that large-scale atmospheric circulation patterns and the Arctic Oscillation determine where and to which extent leads form on weekly to monthly timescales. Events with strong lead openings can directly be associated with pronounced anomalies in wind divergence and sea-ice drift. We also show the dominant modes in the Arctic sea-ice lead variability and their relation to atmospheric circulation. Moreover, the role of ocean processes in shaping long-term spatial lead patterns in the Arctic Ocean is presented. Implications for sea-ice modelling, forecasts and future trends are discussed.
Effect of regulating upstream reservoir on water supply security facing saltwater intrusion
Authors: Wu Haiou
Published: March 2024

Freshwater availability in coastal cities is severely threatened by saltwater intrusion during the dry season. Some reservoirs are typically installed in the upper reaches to regulate the temporal distribution of water resources to ensure a steady supply. However, studies quantifying this effect are limited. This study improved a framework proposed by our previous work and conducted some scenario-based experiments to evaluate this effect. The study considered the following: First, a comprehensive matrix index is developed based on the D-vine copula function and Kendall distribution transformation method (KF) using historical monthly streamflow. Then, several monthly-based management scenarios, i.e., flat, descending, ascending, convex, and concave, are designed based on the index. The scenarios provide inputs to the water supply system facing saltwater intrusion. The Zhuhai-Macao water supply system was taken as a case study. Results demonstrated that the index performed satisfactorily in devising scenarios and holistically describing the temporal streamflow distribution characteristics and hydrological wetness-dryness conditions. The security situation of scenarios followed ascending>convex>descending>flat>concave with KF=0.10 and convex>ascending>flat>descending>concave with KF=0.05. Hence, the securest scenario for regulating reservoirs was the convex pattern, which avoided shortages by 100% and improved the increment of the remaining water in reservoirs by 4.92 times under KF=0.05 and 6.13 times under KF=0.10, separately, compared to the original streamflow. The worst scenario for regulating reservoirs was the concave pattern. Moreover, the ascending pattern can also be considered as a distribution for regulation, but the long period of extremely low streamflow in the early dry season should be avoided. The scenarios experiment can be applied as a management tool to alleviate water supply pressures in coastal cities facing saltwater intrusion.
Identifying rocket launches for space missions using infrasound detections across the IMS
Authors: Pilger Christoph , Hupe Patrick , Gaebler Peter
Published: March 2024

During the last 20 years, an increasing number of rocket launches for space missions per year was conducted from various space ports all around the world. These missions were mainly launched to place satellites in Earth’s orbit, but also for space station flights and the exploration of the Moon and other bodies in the solar system.  Rocket launches can be detected at infrasound arrays in thousands of kilometers distance. We use infrasound data from stations of the International Monitoring System (IMS) for the Comprehensive Nuclear-Test-Ban Treaty (CTBT) to identify and characterize rocket launches all over the world.We present selected cases of interest, including the latest NASA Artemis 1 Space Launch System and SpaceX Starship launches as well as airborne rocket starts and small-lift launches by different companies. Furthermore, we highlight a systematic analysis of infrasound recorded from multiple and regularly launched vehicles like Ariane 5, Falcon 9, and various Soyuz and Long March rocket types.  
The hypothesis of the bottom of the permafrost in Spitsbergen and its overall "shape" - a case study from Hornsund
Authors: Marciniak Artur , Majdański Mariusz , Dobiński Wojciech , Cader Justyna
Published: March 2024

The permafrost-covered areas in polar regions face rapid changes in the current climate. While the active layer and permafrost zone near the surface are well-studied, the precise boundaries of the bottom permafrost remain unclear. Consequently, there is insufficient accuracy in understanding the overall shape of permafrost between the upper and lower boundaries. The evolution of deep cryotic structures, influenced by subsurface factors, is also relatively unknown.In this study, based on the results of seismic reflection imaging we propose a hypothesis regarding the permafrost shape in the coastal area of Svalbard, Southern Spitsbergen. Additional Ground penetrating radar survey using a low-frequency antenna, as well as results of previous researches based on multiple geophysical methods, allowed for correlation of the obtained seismic results with surface observations. The entire methods were complemented by synthetic modeling, in order to better understand the obtained data. The work emphasizes the importance of recognizing not only the upper active layer but also the bottom permafrost boundary and its transition zone due to the underestimated potential role in observing climatic changes. The estimated bottom permafrost border ranges from 70 m below the surface near the shore to 180 m deep further inland, with a continuous frozen matrix layer identified between 40 m and 100 m depth. We also present a hypothesis about the possible presence of subsea permafrost in the Hornsund.Factors such as seawater intrusions, isostatic uplift of deglaciated areas, and surface-related processes influencing permafrost evolution may lead to extensive changes in the hydrology and geology of polar regions in the future. Therefore, global attention and scientific efforts are essential for monitoring, geophysical imaging, and understanding the characteristics and evolution of deep permafrost structures. The research presented here forms the basis for a full understanding of permafrost evolution and degradation, and should be repeated across the globe to monitor climate change on a worldwide scale.
A granular numerical model for the friction and wear of a lab-scale fault asperity
Authors: Mollon Guilhem , Clerc Adriane , Ferrieux Amandine , Lafarge Lionel , Saulot Aurelien
Published: March 2024

Seismic faults are often represented using two different and self-excluding conceptual models. In the first representation, seismic faults are seen as the interface between two surfaces of bare rock, with a roughness extending at all scales. These surfaces interact mechanically through a certain number of “asperities” which constitute the “real contact area”. When adopting this view, attention is paid on the statistics of the asperities population in the fault plane. Faults are thus considered as 2D objects, since their thickness is disregarded.In the second representation, seismic faults are seen as mathematical planes separated by a certain thickness of granular gouge created by abrasive wear of the surfaces during previous slips. This view is analogous to the tribological “third body” theory, and is supported by field observations and experimental evidences of gouge creation in rotary shear and triaxial experiments. It is convenient to adopt this perspective when weakening phenomena within the gouge are to be spatially resolved in the direction orthogonal to the fault plane. Variations along this plane are then ignored, as well as fault roughness, and faults are mostly seen as 1D objects.Unification of these two representations requires a better understanding of the interactions between geometrical asperities and a layer of gouge, and in particular of the phenomena that lead to the creation of the latter through the wear of the former. In this communication, we present a numerical model which aims at reproducing lab tests of millimetric single-asperity friction and wear. The model is essentially granular in order to represent the progressive degradation of the asperity along sliding, the separation of powdery matter, its successive ejection and reinjection by the contact (thanks to a periodicity in boundary conditions), and the build-up of a gouge layer. It also includes a coupling with continuum mechanics in order to maintain a meaningful stress field in the asperity beyond the region of degradable rock.Numerical results show that: (i) the rate of wear of the asperity and the counterface are directly linked to the normal load applied to the contact; (ii) an established layer of gouge develops in the interface and controls the friction coefficient; (iii) a constant level of surface roughness is established after a sufficient sliding distance, both for the asperity and the counterface; (iv) an accurate control of the asperity boundary conditions is necessary in order to obtain repeatable friction and wear. These results are a first step towards a better understanding of the wear kinetics as a function of asperity geometry, load, and roughness, before the introduction of thermal aspects (including melting) in a future version of the model.
BirdWatch - a Copernicus-based service for the improvement of habitat suitability of farmland birds in the EU
Authors: Frick Annett , Scholz Nastasja , Gey Sascha , Zurell Damaris , Wiedenroth Levin , Kadunc Nika Oman , Vesel Nejc , Rosier Ine , Hendrix Rik , de Meyer Annelies , Sonnenschein Ruth , Tufail Basil , Ventura Bartolomeo , Orlickas Tomas , Rimgaila Martynas
Published: March 2024

BirdWatch, funded by the Horizon Europe Program, focuses on improving the state of biodiversity of the EU's agricultural landscape, in line with major policy targets of the EU Green Deal, the EU Biodiversity Strategy for 2030, and the Farm to Fork Strategy. A healthy agricutural ecosystem forms the necessary basis for the provision of nature-based solutions and, eventually, for the resilience of our society.Leveraging Copernicus satellite data, the project assesses agricultural areas to identify their suitability for farmland birds and strategises ways to enhance ecological conditions. As indicator species, birds offer insights into overall biodiversity health, contributing to a broader understanding of ecosystem well-being.The project employs species distribution modeling to link bird occurrence data with habitat requirements, establishing models that gauge habitat suitability and the likelihood of an area being suitable for specific bird species. Utilising remote sensing data, BirdWatch quantifies essential environmental descriptors such as structural variability, land cover type, crop type, mowing intensity and soil moisture. These parameters are then fed into the habitat models to assess landscape suitability.Knowing the state of habitat suitability and the habitat requirements, BirdWatch identifies which of the agroecological schemes under the EU’s Common Agricultural Policy (CAP), have to be applied to improve the farmland conditions. The agri-environmental schemes are selected in such a way to ensure that they are not in conflict with any spatial or ecological requirements.Here, BirdWatch uses spatial optimisation, taking into account both the ecological requirements and the economic and operational constraints of the farmers who need to implement the agri-environmental measures as part of their obligations under the CAP.Benefiting from Copernicus program's high temporal resolution, BirdWatch evaluates the success of agri-environmental measures and makes adjustments as needed.Upon project completion, the service will be accessible through a web-based GIS application in the project regions of Flanders, Germany, Lithuania, and South Tyrol.
Seismic insights into the structure of the Balmuccia Peridotite within the Ivrea Verbano Zone
Authors: Pasiecznik Damian , Greenwood Andrew , Bleibinhaus Florian
Published: March 2024

In the Ivrea Verbano Zone (IVZ) Italy, which is characterized with lower-crustal rocks and fragments of upper mantle rocks, a high-resolution seismic survey is conducted across the Balmuccia Peridotite. This study is in preparation of a proposed deep scientific drilling project which focuses on targeting mantle rocks and understanding the region's complex geology. Specifically, we target characterizing structures within the peridotite body.The seismic survey employs a fixed spread of 200 vertical geophones and 160 3C-sensors, spaced at ca. 10 m along three sub-parallel receiver lines spaced 40-80 m apart. Vibroseis source points are at 22 m stations along a 2.2 km line utilizing a 12-140 Hz 10 s linear sweep with 3 s listening time. The survey aims to explain the seismic characteristics of the peridotite body and its relation to the surrounding geological structures.The P-wave traveltime tomography reveals a range of seismic velocities within the peridotite from 6 to 8 km/s, with a mean velocity of ca. 7 km/s. These variations reflect the heterogeneity of the peridotite, influenced by the presence of fractures and faults. Notably, the higher velocities observed are consistent with findings from laboratory studies on small-scale samples from the area. The reflection seismic analysis shows subvertical reflectors that coincide with the peridotite boundaries mapped at the surface. These reflectors come together at a depth of 0.175 km b.s.l., suggesting that the peridotite has a lens-like structure. In addition, several features within the peridotite suggest a highly fractured body. Nevertheless, limitations in the imaging process do not allow for a thorough interpretation of the area below the imaged lens-shaped body. A deep reflector is identified at approximately 1.3 km depth. This feature potentially marks the top of the Ivrea Geophysical Body (IGB), aligning with previous geophysical estimations.
Estimating nitrogen and sulfur deposition across China during 2005-2020 based on multiple statistical models
Authors: Zhou Kaiyue , Zhao Yu
Published: March 2024

Due to the rapid development of industrialization and substantial economy, China has become one of the global hotspots of nitrogen (N) and sulfur (S) deposition following Europe and the USA. Here, we developed a dataset with full coverage of N and S deposition from 2005 to 2020, with multiple statistical models that combine ground-level observations, chemistry transport simulations, satellite-derived vertical columns, and meteorological and geographic variables. Based on the newly developed random forest method, the multi-year averages of dry deposition of oxidized nitrogen (OXN), reduced nitrogen (RDN) and S in China were estimated at 10.4, 14.4 and 16.7 kg N/S ha−1 yr−1, and the analogous numbers for total deposition were respectively 15.2, 20.2 and 25.9 kg N/S ha−1 yr−1 when wet deposition estimated previously with a a generalized additive model (GAM) was included. The dry to wet deposition ratio (Rdry/wet) of N stabilized in earlier years and then gradually increased especially for RDN, while that of S declined for over ten years and then slightly increased. The RDN to OXN deposition ratio (RRDN/OXN) was estimated to be larger than 1 for the whole research period and clearly larger than that of the USA and Europe, with a continuous decline from 2005 to 2011 and a more prominent rebound afterwards. Compared with the USA and Europe, a more prominent lagging response of OXN and S deposition to precursor emission abatement was found in China. The OXN dry deposition presented a descending gradient from east to west, while the S dry deposition a descending gradient from north to south. After 2012, the OXN and S deposition in eastern China declined faster than the west, attributable to stricter emission controls. Positive correlation was found between regional deposition and emissions, while smaller deposition to emission ratios (D/E) existed in developed eastern China with more intensive human activities.
Intensification of the Antarctic slope current due to freshwater forcing in a warmer climate
Authors: Kim Myeong-Hyeon , Yi Gyuseok , Lee June-Yi , Timmermann Axel , Park Wonsun , Lee Sun-Seon
Published: March 2024

The Antarctic slope current (ASC) flows westward along the Antarctic coastlines and influences heat exchange across the Antarctic continental shelf. Therefore, it could play an important role in regulating the Southern Ocean circulation by affecting processes such as ice melting and water mass formation. However, clarifying the mechanism and change of ASC in future climate using high-resolution climate model is still challenging. We showthat ASC is projected to accelerate in response to CO2 increases by comparing present-day and CO2 increased simulations (2×CO2 and 4×CO2)conducted with the fully coupled ultra-high-resolution Community Earth System Model. The intensification of ASC was attributable to an increase in the gradient of sea surface height due to a decrease in salinity through geostrophic balance. This freshening was dominated by sea ice melting, while increases in runoff and precipitation minus evaporation played a minor role with regional and seasonal dependence. These results increased understanding about the future change of ASC using high-resolution simulations and have important implications for changes in mesoscale ocean circulation and the climate of Southern Ocean.
Breaking New Ground in Venusian Atmospheric Sulfur Chemistry
Authors: Frandsen Benjamin , Skog Robert
Published: March 2024

The Venusian atmosphere has rich and diverse chemistry and much of it remains to be explored. Here I present our recent work in identifying new reactions and quantifying their rate constants, along with UV-Vis spectral simulation using quantum chemistry calculations. The research focuses on elemental sulfur allotropes and sulfur oxides. Our UV-Vis spectral simulations are used to narrow the search of the unknown UV absorber by excluding molecules/isomers/conformers without the appropriate absorption and similarly include those with absorption profiles that fit the unknown absorber. Furthermore, we present a mechanism for how substituted sulfuric acid molecules can be formed in the Venusian atmosphere which can impact aerosol formation.
Nowcasting with Transformer-based Models using Multi-Source Data 
Authors: Küçük Çağlar , Giannakos Apostolos , Schneider Stefan , Jann Alexander
Published: March 2024

Rapid advancements in data-driven weather prediction have shown notable success, particularly in nowcasting, where forecast lead times span just a few hours. Transformer-based models, in particular, have proven effective in learning spatiotemporal connections of varying scales by leveraging the attention mechanism with efficient space-time patching of data. This offers potential improvements over traditional nowcasting techniques, enabling early detection of convective activity and reducing computational costs. In this presentation, we demonstrate the effectiveness of a modified Earthformer model, a space-time Transformer framework, in addressing two specific nowcasting challenges. First, we introduce a nowcasting model that predicts ground-based 2D radar mosaics up to 2-hour lead time with 5-minute temporal resolution, using geostationary satellite data from the preceding two hours. Trained on a benchmark dataset sampled across the United States, our model exhibits robust performance against various impactful weather events with distinctive features. Through permutation tests, we interpret the model to understand the effects of input channels and input data length. We found that the infrared channel centered at 10.3 µm contains skillful information for all weather conditions, while, interestingly, satellite-based lightning data is the most skilled at predicting severe weather events in short lead times. Both findings align with existing literature, enhancing confidence in our model and guiding better usage of satellite data for nowcasting. Moreover, we found the model is sensitive to input data length in predicting severe weather events, suggesting early detection of convective activity by the model in rapidly growing fields. Second, we present the initial attempts to develop a multi-source precipitation nowcasting model for Austria, tailored to predict impactful events with convective activities. This model integrates satellite- and ground-based observations with analysis and numerical weather prediction data to predict precipitation up to 2-hour lead time with 5-minute temporal resolution.  We conclude by discussing the broad spectrum of applications for such models, ranging from enhancing operational nowcasting systems to providing synthetic data to data-scarce regions, and the challenges therein.
Spatial variations of eddy vertical structure and energy in the southeastern Indian Ocean
Authors: He Yinghui , He Qingyou , Liu Tongya , Cai Shuqun
Published: March 2024

Satellite observations demonstrate that mesoscale eddies are active and show significant spatial variability of surface features in the southeastern Indian Ocean (SEIO). Combining the satellite observation and Argo floats data, this study reveals the spatial variation of eddy vertical structure and volume-integrated energy in the SEIO. The sources of surface-intensified and subsurface-intensified eddies correspond well to the mean current systems. The surface-intensified cyclonic eddies (CEs) mainly originate from the South Indian Countercurrent system, whose density core is at a depth of ≈70 m, and subsurface-intensified CEs mainly originate from the Leeuwin Current system (LCS, ≈10° longitude off the eastern boundary of south Indian Ocean) and the SEIO interior south of 30°S, whose density core and maximum velocity are at depths of ≈750 m and ≈290 m, respectively. The surface-intensified anti-cyclonic eddies (AEs) widely originate from the entire region of SEIO, whose density core is at a depth of ≈110 m, while the sources of subsurface-intensified AEs only scatter in a few regions. The eddy lifespan in the SEIO is significantly correlated with the eddy volume-integrated energy. The most important factor affecting the spatial variability of eddy energy in the SEIO is eddy vertical structure, followed by the eddy amplitude. Finally, by investigating the performance of two reanalysis data in eddy statistical properties, we find that the biases of eddy lifespan and movement distance in the LCS is caused by the bias of eddy vertical structure. This further confirms the impact of the eddy vertical structure on the eddy evolution.
Magma-induced tectonics at the East Pacific Rise 9º50’N: Evidence from high-resolution characterization of seafloor and subseafloor 
Authors: Marjanovic Milena , Chen Jie , Escartín Javier , Parnell-Turner Ross , Wu Jyun-nai
Published: March 2024

Mid-ocean ridges host the most extensive magmatic system on Earth, where ~60% of the lithosphere is formed. Fast spreading segments such as the East Pacific Rise (EPR) 9º50’N (full spreading rate >80 mm/yr) represent only ~20% of the global ridge network, but contribute ~50% of the total oceanic crustal accretion.  At these ridge segments, magma accumulates in on-axis, quasi-steady-state axial magmatic lenses (AML), typically found 1-2 km below the seafloor, 2 km wide on average, and
Post-eruptive emission of metals and metalloids from basaltic lavas
Authors: Levillayer Nicolas , Sigmarsson Olgeir , Mandon Céline
Published: March 2024

During basaltic eruptions, degassing occurs both syn- and post-eruptively. The atmospheric loading resulting from the latter, taking place as the lava cools down and solidifies, is poorly characterised and its environmental impacts are largely unknown. Characterising post-eruptive degassing can be attempted either by direct sampling of the gas emitted at solidifying lava flow or by analysing the degassing structure (segregation veins and vesicles) from already crystallised lava bodies. The 2021-2023 eruptions at Fagradalsfjall on the Reykjanes Peninsula, Iceland, allowed sampling of both the syn- and post-eruptive gas phases. Segregation veins from prehistorical olivine tholeiite lavas of similar composition to that of Fagradalsfjall have been collected, together with their host lava. Major and trace volatile element concentrations, particularly those of the toxic volatile metals and metalloids (VMM), were analysed in the gas and rock phases. The gas analyses reveal distinct VMM composition of the gas emitted syn- and post-eruptively, with a clear tendency for Zn, Mo and Sb to degas after the eruption, whereas Te, Cd and Bi are predominantly released syn-eruptively. Among the segregation veins sampled, several showed anomalous enrichment in numerous VMM, indicative of the post-eruptive gas phase composition. Molybdenum is largely enriched in these veins whereas Cd enrichment is low, reflecting gas phase rich in the former but poor in the latter. Taken together, both approaches indicate substantial atmospheric loading of As, Pb, Sb and Mo post-eruptively resulting in potential hazard around newly erupted lava bodies.
Global chemical weathering patterns set by glacial erosion
Authors: Li Xiangying , Wang Ninglian , Ding Yongjian , Wang Rongjun , Raiswell Robert , Zhang Shiqiang , Liu Qiao , He Xiaobo , Han Haidong , Han Tianding , Yu Zhengliang , Mitchell Andrew C. , Yi Tong
Published: March 2024

Chemical weathering plays a crucial role in the long-term evolution of Earth’s climate, yet the spatial heterogeneity of the weathering rate and intensity driven by glacial erosion owing to glacial shrinkage worldwide is poorly constrained. Here we develop a global data set of cation denudation rate (CDR) and intensity (CDI) from mountain ranges, glacial regions and glacial catchments worldwide. Contemporary weathering rate and intensity are ~ 2 times higher than two decades ago, 2 ~ 6 times higher than Greenland ice sheet basins and over 2 times higher than whole ice sheet means. Their spatial patterns are characterized by relatively high weathering rate and intensity in low latitudes in contrast to low weathering rate and intensity in high latitudes. This is closely related to glacial erosion involving with temperature, precipitation, discharge, altitude and slope, suggesting that the element mobilization and CO2 budgets caused by glacial chemical weathering are likely to enhance in a warming landscape. We contend that subglacial chemical weathering is far more important than previously thought and should be considered in elemental cycles and carbon cycling.
Evolution of atmospheric methane clumped isotope anomalies since the 1990s reconstructed from firn air measurements
Authors: Sivan Malavika , Sun Jiayang , Röckmann Thomas , Martinerie Patricia , Farquhar James , Krol Maarten C. , Paandey Sudhanshu , Menoud Malika , Dasgupta Bibhasvata , Hagnegedar Mojhgan A. , Veen Carina van der , Popa Maria Elena
Published: March 2024

The global atmospheric methane mole fractions have risen since the pre-industrial times, primarily attributed to anthropogenic emissions, overlayed by significant multi-annual variability. Atmospheric methane is influenced by different methane sources, variations in the atmospheric OH concentration and other sink reactions. Understanding the contribution of each of these factors is crucial for a comprehensive understanding of the methane cycle.Recent modelling studies have suggested that measurements of clumped isotopologues (13CH3D and 12CH2D2) can help constrain the global methane budget [1,2]. The first measurements of present ambient air (2022-23) show that the clumping anomalies of atmospheric methane have distinct signatures of about 1 ± 0.3 ‰ for Δ13CH3D and 44 ± 3 ‰ for Δ12CH2D2, strongly enriched in Δ12CH2D2 compared to all known sources [3,4].We have measured the bulk and clumped isotope composition of methane from firn air samples (~ 500 L volume) collected at the East Greenland Ice core Project (EGRIP) site in high-pressure cylinders. At this location, open porosity allows the collection of air samples from firn down to a depth of 70 m, dating back to the 1990s.These are the first-ever measurements of the clumped isotopic composition of atmospheric methane from the past. Results of bulk isotope measurements are in line with the known temporal evolution, supporting the integrity of the sampling and analysis procedure. The clumped isotope results reveal a clear increase of 10 ± 2 ‰ for Δ12CH2D2 over the last 30 years (~1993 to 2018), while Δ13CH3D remains constant within the experimental uncertainty. We use a 2-box atmospheric model to investigate source and sink scenarios that are consistent with this trend in the clumped isotope anomalies as well as the bulk isotopic composition of methane.References:1.https://doi.org/10.1029/2020GB0068832.https://doi.org/10.1002/2017GB0056553.https://doi.org/10.1073/pnas.23055741204.https://doi.org/10.5194/egusphere-2023-19
Early Cretaceous lignites as archive for continental climates of paleo-Asia
Authors: Stoepke Fritz-Lukas , Littke Ralf , Burnaz Linda , Zieger Laura , Hasegawa Hitoshi , Ichinnorov Niiden , Heimhofer Ulrich
Published: March 2024

The late Early Cretaceous interval (121.4 to 100.5 Ma) was characterized by a gradual warming trend superimposed on an already warm greenhouse climate. Whereas the evolution of ocean temperatures during this time interval is relatively well constrained, information on the response of continental interiors to such climatic extremes is limited. Here we report new data from two continental sections (Shivee Ovoo (SVO) and Tevshin Gobi (TSG); Choir-Nyalga Basin) from central Mongolia, which contain thick, lignite-rich successions (Khukhteeg Fm.) bearing an exceptionally well-preserved fossil flora of various pine and redwood species as well as representatives of extinct seed plant lineages. In order to reconstruct the palaeoenvironmental conditions, a combined approach including brGDGT-based palaeothermometry, coal petrology and palynology is applied, complemented by geochemical measurements (TOC, TS, δ13Corg). The investigated lignites show significant differences in maceral compositions with the TSG samples being rich in mineral detritus and mainly composed of huminite. In contrast, samples from SVO show higher fusinite and liptinite content with generally low mineral detrital contribution. The paleotemperature estimates represent the oldest brGDGT analyses obtained from continental strata so far. The new data indicate that the climatic conditions in mid-latitudes of paleo-Asia during the late Early Cretaceous were characterised by mean annual air temperatures of about 12 ± 5°C. Our brGDGT data show lower continental temperatures for mid-latitude paleo-Asia than previously suggested based on modelling. 
Navigating the Academic Landscape: Intelligent Retrieval Systems for Geoscience Exploration
Authors: Xu Yi , Deng Cheng , Cai Shuchen , Xue Bo , Wang Xinbing
Published: March 2024

The surge in academic publications mirrors the evolutionary strides of human civilization, marked by an exponential growth in their numbers. Addressing the lacuna in well-organized academic retrieval systems for geoscientists, the Geo-Literature system emerges as a transformative tool. This system, boasting a vast repository of over seven million papers and information on four million scholars, employs cutting-edge technology to reshape the landscape of academic search, analysis, and visualization within the geoscience domain.Driven by the necessity to bridge the gap between modeling frameworks and geological constraints, Geo-Literature incorporates geoscience knowledge mining and representation technologies. Through its intelligent update and fusion system, it not only integrates new publications but also analyzes language, space, and time relationships, effectively overcoming challenges posed by knowledge ambiguity. The platform's geoscience knowledge interaction and presentation technology facilitate intelligent retrieval, recommendation systems, and the creation of comprehensive scholarly portraits.The impact of Geo-Literature transcends conventional academic boundaries. Establishing associations, mapping key attributes, and providing hierarchical visualizations, the system assists researchers in uncovering knowledge and forming a nuanced understanding of the academic space in geosciences. Consequently, Geo-Literature not only enhances the efficiency of paper retrieval but also contributes to broader scientific goals by fostering interdisciplinary collaboration and advancing our comprehension of Earth's deep-time processes.
Blending machine-learning and mesoscale numerical weather prediction models to quantify city-scale heat mitigation
Authors: Zhao Yongling , Wang Zhi , Strebel Dominik , Carmeliet Jan
Published: March 2024

Urban warming in cities is increasingly exacerbated by the escalation of more frequent and severe heat extremes. Effectively mitigating overheating necessitates the adoption of a comprehensive, whole-system approach that integrates various heat mitigation measures to generate rapid and sustained efficacy in mitigation efforts. However, there remains a significant gap in the exploration of how to quantify the efficacy of mitigation strategies at the city-scale.We address this research question by leveraging mesoscale Weather Research Forecasting (WRF) models alongside machine-learning (ML) techniques. As a showcase, ML models have been established for Zurich and Basel, Switzerland, utilizing seven WRF-output-based features, including shortwave downward radiation (SWDNB), hour of the day (HOUR), zenith angle (COSZEN), rain mix ratio (QRAIN), longwave downward radiation (LWDNB), canopy water content (CANWAT), and planetary boundary layer height (PBLH). Impressively, the resultant median R2 values for T2 (2m temperature) predictions during heatwave and non-heatwave periods are notably high at 0.94 and 0.91 respectively.Within the perspective of the whole-system approach, we quantify the impacts of reducing shortwave radiation absorption at ground surfaces, a potential result of a combination of both shading and reflective coating-based mitigation measures, through the utilization of ML models. Remarkably, a 5% reduction in the absorption of radiation at ground surfaces in Zurich could lead to a reduction in T2 by as much as 3.5 °C in the city center. During a heatwave in Basel, the potential for cooling is even more pronounced, with temperature decreases of up to 5 °C. These case studies in Zurich and Basel underscore the efficacy of utilizing WRF feature-trained ML models to quantify heat mitigation strategies at the city-scale.
Introducing a new ground-based Radiation belt electron enhancement events catalog
Authors: Nguyen Gautier , Bernoux Guillerme , Maget Vincent
Published: March 2024

Electron radiation belt enhancement events are a key phenomena of the Earth geomagnetic activity and have been thoroughly studied in the literature.Establishing extensive catalogs of these events automatically is a key asset to both the global statistical study of the electron radiation belt enhancement and, from an operational perspective, to provide actionable scenario-based forecasts. The latter being the objective of the EU Horizon Europe FARBES (Forecast of Actionable Radiation Belts Scenarios) under which this work is funded.Nowadays, the existing attempts of establishments of such catalogs are scarce and often based on the exceedance of certain thresholds of ground-based measurements (Bernoux and Maget, 2020) or onboard electron fluxes (Reeves et al. 2020). Which often leads to missed events, non-events or events with unrealistic boundaries.In this work, we introduce a novel automatic detection method of radiation belt enhancement events based on the Ca index (Rochel et al. 2016), a simple 1D-proxy representative of the state of the electron radiation belts for average energies (up to  MeV). This method is then used to produce an extensive catalog of events between 1870 and 2023 with more realistic boundaries. The most recent events of this catalog (detected after 1995) are then associated with their possible physical cause, whether it be Interplanetary Coronal Mass Ejections (ICMEs) or Streaming-Interaction regions (SIRs).