bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving the spatiotemporal representation of anthropogenic CO2 and co-emitted species to support verification using earth observations
Authors: Guevara Marc , Tena Carles , Jorba Oriol , Dellaert Stijn , Denier van der Gon Hugo , Pérez García-Pando Carlos
Published: March 2024

A correct representation of the spatial and temporal distribution of anthropogenic emissions is important for verification of global CO2 emissions through current and future satellite emission monitoring. This work presents the results derived from the CoCO2 and CORSO Horizon Europe projects on improving the spatiotemporal representation of CO2 and co-emitted anthropogenic bottom-up emissions (i.e., CO, NOx) as part of the CO2 Monitoring and Verification Support capacity (CO2MVS) developments. The global CO2MVS system is envisioned to become a part of the European Union’s Copernicus Atmosphere Monitoring Service (CAMS). To improve the emission timing, we built a new set of activity and meteorology based global temporal profiles for the road transport, residential combustion, aviation, shipping and energy industry sectors. Their associated uncertainty is quantified by creating an ensemble of profiles from different years / countries / oceans and seas, so that the full range of possibilities is included. Regarding the improvement of the spatial representation, we constructed a global point source emission catalogue that contains emission information for individual facilities at their exact geographical location. The two developed datasets were compared against state-of-the-art bottom-up emission inventories that are widely used in modelling efforts, including the Emissions Database for Global Atmospheric Research (EDGAR), as well as independent TROPOMI satellite-based estimates for the co-emitted species. Main discrepancies between datasets were found in developing regions where information to derive bottom-up emissions such as energy use or pollution control strategies is still poorly characterized, indicating the need to complement the information with top-down estimates.
Increasing the Spatial Resolution in CLEWs Studies: An Integrated Modelling Approach for Water-Energy-Food Systems
Authors: Sadak Derya , van de Giesen Nick , Abraham Edo
Published: March 2024

Integrated modelling of energy and water systems in the CLEWs (Climate, Land, Energy, and Water-systems) framework has significantly advanced our understanding of the intricate interactions among scarce sources such as water, energy, and food. This framework brings meaningful insights and quantitative results using modelling tools aligned with practical planning scenarios. Accordingly, this nexus approach enables policy and scenario analyses tailored to the sustainable development goals and the specific needs of countries, governments, and sectoral authorities.Some open-source modelling tools provide a broad interface for incorporating water and energy planning assessments, which contribute to the development of various soft-linking models. In general, open-source energy modelling systems (such as OSeMOSYS) facilitate the simulation and optimization of energy systems on a regional and national level. However, OSeMOSYS has a notable limitation in modelling the spatial distribution of energy sources, demand, and infrastructure. In particular, the geographical location of energy sources impacts various factors, such as extraction costs, transmission and distribution efficiency, and environmental concerns such as carbon emissions.This study aims to develop an integrated modelling approach for these associated costs, environmental impacts, and potential interdependencies between energy and water systems by explicitly capturing the spatial distribution of energy storage, energy sources, demand, and supply infrastructure. Integrating the Next Energy Modeling system for Optimization (NEMO), Water Evaluation and Planning (WEAP), and Geographic Information System (GIS) analysis aims to identify optimal energy pathways considering environmental aspects, cost-effectiveness, and sustainable development goals. The proposed methodology aims to enable dispatch modelling of energy options with a sufficient temporal resolution and structure the interactions of CLEWs by explicitly accounting for the spatial distribution of energy sources, water resources, and infrastructure. This approach can provide a more accurate assessment of interdependencies and potential trade-offs.The research outcomes will contribute to basin management and CLEWs studies, advancing the understanding of energy-water dynamics and offering insights into sustainable solutions for the Volta and Tana River Basins, in West and East Africa respectively. We present a systematic outline of our project and a preliminary example of an energy transition in the Volta River Basin using a spatially explicit modelling approach.   
Block-structured grids for finite element models of coastal ocean
Authors: Schmalfuß Jonathan , Faghih-Naini Sara , Zint Daniel , Aizinger Vadym
Published: March 2024

For numerical models of the ocean, the choice of the underlying grid is a crucial technical decision affecting the accuracy, stability, computational performance, and, ultimately, modeling skill. This is a particularly important issue for high-resolution simulations of coastal and regional oceans, where a precise representation of irregular land boundaries and geometric features such as islands, channels, rivers, etc. is a key requirement. For these types of applications, unstructured triangular meshes are often the preferred type of horizontal mesh due to their adaptability and ease of construction. However, optimizing the computational performance of unstructured mesh codes on many modern hardware architectures is quite challenging compared to doing the same for stencil-based numerical schemes used in structured grid models. As a viable alternative to unstructured meshes, we propose block structured grids (BSGs) consisting of a topologically unstructured mesh of blocks, each of which is partitioned using a structured grid. Our methodology allows to automatically generate BSGs for realistic ocean domains with a prescribed number of blocks of given resolution already load-balanced for execution on a parallel computer of given configuration. To allow generating BSGs for ocean domain geometries and topographies of varying complexity our approach supports three different types of BSGs:1. standard BSGs -- very computationally efficient but only practical for rather simple geometries2. masked BSGs -- an extension of the standard BSGs that permits masking of elements to allow meshing of small geometric features using large blocks3. hybrid BSGs -- an entirely new method combining structured with unstructured blocks to offer the optimal compromise between geometric accuracy and computational efficiencyWe present grid generation techniques, validation of simulation results, and computational performance evaluations for the proposed methods.
Fine scales structures of the Abrolhos Bank circulation from SWOT data early results
Authors: Hernandez Fabrice , Costa Alex , Silva Marcus
Published: March 2024

In the frame of the SWOT satellite cal/val initiative in Brazil, the University Federal of Pernambuco ship Ciencias do Mar IV has performed successive survey in May and September 2023 over the Abrolhos Bank (17-20°S along the Brazilian coast). In situ measurements, as well as moored data have been collected, in order to be compared to SWOT sea surface height retrievals, but also Copernicus Marine Service operational products in quasi-real time. The objective of this work are two-fold. First characterize the coastal to open ocean continuum of ocean variability in this shallow area during the surveys, and second evaluate both the SWOT and operational oceanography products in providing realistic representation of the high frequency scales. The first results show the dominance of the tidal dynamics over the Banks, and the influence of the wind and the sea-state variability. However, the Brazil Current patterns and associated mesoscales features are well captured by satellite data and models. Further work will evaluate the benefit of SWOT short scale information to improve our understanding of meso to submesoscale interactions in the area.
Multiscale remote sensing assessment of water cycle modelling outputs  
Authors: Pascual Sanchez Diana , Batlle Amanda , Flo Eva , Otsu Kaori , Prat Ester , Garcia Xavier , Pesquer Lluís
Published: March 2024

The selection of a suitable spatial resolution for the inputs and outputs of many types of modelling is crucial in most of requirements analysis.The easy and quick solution, the highest possible spatial resolution, is not always feasible, or at least, is not the best in terms of cost – benefit.This work aims to analyse and assess the outputs of the water quantity SWAT (model (https://swat.tamu.edu/) at different spatial detail and fragmentation of HRUs (hydrologic response units) and the corresponding validation with remote sensing products at different spatial resolutions.This work is being developed within the framework of the AquaINFRA project (https://aquainfra.eu/) which creates an EOSC-based (https://eosc-portal.eu/) research infrastructure for an integrated vision of the hydrosphere (inland + marine). Thus, our goal is to validate selected model outputs from inland and marine components in one of the project use cases.The study area of the use case is located in the northwest Mediterranean region, specifically in the central Catalonia coast:  the Tordera river basin (898 km2) and the connected coastal neighbouring of its mouth. The inland landscape is mainly a heterogeneous mosaic of forests (upper river basin) and shrublands, croplands, and urban + industrial zones (lower river basin). This area shows an 800 mm mean annual precipitation and 13 ºC mean annual air temperature.This study starts with the multiscale analysis of the evapotranspiration (ET): monthly time series (2011-2022) intercomparison between SWAT modelling outputs at different numbers of HRUs (range 261 - 1958) and the remote sensing ET products: from MODIS (500m) to Landsat (30m) and other modelling products, such as C3S (Copernicus Climate Change Service; 10km). Some of the outputs from the inland model are selected as inputs for the regional coastal model (MitGCM + BFM), where again, the most suitable spatial resolution is a key property for the integrated models.(This project has received funding from the European Commission’s Horizon Europe Research and Innovation programme under grant agreement No 101094434).
Ether and ester formation from peroxy radical recombination
Authors: Franzon Lauri , Kurtén Theo , Aumont Bernard , Camredon Marie , Valorso Richard
Published: March 2024

In a recent combined experimental and computational investigation (Peräkylä et al, JACS 145,35 7780–7790, 2023) of the Peroxy Radical Recombination (RO2 + RO2) products of α-pinene, we discovered a previously unknown product channel, in which the expected attachment of the two alkoxy radical (RO) intermediates into a peroxide accretion product (ROOR) is preceded by a rapid decomposition of one of the intermediate RO into an acyl-centered radical, resulting in the formation of a smaller but more stable ester accretion product R’(O)COR. In the presented work, the atmospheric implications of this new reaction channel have been explored further using a modified version of the GECKO-A (Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere, Aumont et al, ACP 5, 2497–2517, 2005) to generate a large representative sample of RO2 + RO2 reactive pairs from the atmospheric oxidation of n-Decane, Toluene, the seven most common Monoterpene molecules) and one Sesquiterpene along with all the known decomposition channels of the intermediate RO formed in the reactions. The reaction rates of these decomposition channels are then compared to previous theoretical work on the product branching from RO2 + RO2 reactions (Hasan et al. JPCA, 124, 8305–8320, 2020 & 127, 1686–1696, 2023; Franzon JPCA 127, 5956–5966, 2023) to determine for which systems these RO decompositions might be competitive.The generated chemical data is discussed in terms of the atmospheric formation of low-volatility organic molecules. Data is presented on the most important RO decomposition reactions for ether and ester accretion product formation, on vapour pressure trends of the various products, and on new accretion product-inhibiting reaction channels that at best produce two closed-shell molecules with the same carbon count as the reactant RO2.Since our work is exploratory, and as the calculation of reaction rates rests on many assumptions, no certain conclusions can be drawn from our calculated product branching ratios. However, the present work provides valuable new insights on the formation of low-volatility organics in the atmosphere, and raises many open questions worthy of detailed studies of their own. We hope our results will be of great general interest to the atmospheric chemistry and physics community.
Geothermal prospecting by ground radon and radon/thoron ratio measurements at La Palma, Canary Islands
Authors: Gironés Ana , Valls Anna , Thompson Maisie , Martín Alba , Pérez Nemesio M. , Melián Gladys V. , Padrón Eleazar , Padilla Germán D. , Hernández Pedro A. , Asensio-Ramos María , Rodríguez Fátima
Published: March 2024

Geothermal energy has reached the front line on renewable resources assessment in recent years, especially in active volcanic areas such as the Canary Islands (Spain), and precisely in La Palma island, where a recent volcanic eruption occurred in 2021, representing a unique opportunity to carry out in situ exploration. Cost-effective geochemical surveys, like soil radon (222Rn) and thoron (220Rn) gases activities measurements, have demonstrated to provide relevant insights as part of surface geothermal exploration, helping to identify permeable areas and potential up-flow zones and, therefore, defining potential geothermal systems boundaries. Both radon (222Rn) and thoron (220Rn) are radioactive isotopes of radon gas and are derived from the natural decay of uranium (238U) and thorium (232Th) respectively, present in the mineralogical composition of, particularly, igneous rocks. However, 222Rn present a half-life of 3.8 days while 220Rn has a shorter half-life of 55 seconds. High 222Rn activity surface measurements are considered to be associated to deep magmatic sources of gas, providing additional value on defining high porosity and permeable zones. On the contrary, due to its ephemeral half-life, high 220Rn activity is associated to shallow soil gas sources.A detailed and regular surface geochemical survey was carried out in an area of 25 Km2 at the western side of La Palma island and southwards from the recent lava flow of Tajogaite Volcano. A total of 766 soil radon and thoron activities discrete measurements were performed (around 30 sample sites/Km2) using a SARAD radon monitor, model RTM-1688-2, connected to a stainless steel probe inserted at 40 cm depth. Data analysis and treatment showed an average 222Rn value of 1,056 Bq/m3, ranging from 0 to up to 27,000 Bq/m3, and an average 222Rn/220Rn ratio of 0.3, ranging from 0 to a maximum of 49. The spatial distribution maps has enabled to limit areas with higher values of these two variables,which might indicate zones of interest for further investigation. Higher soil 222Rn activity were concentrated along an specific segment of the coast line, which is coincident with the distribution of the well-known anomalous CO2 active diffuse degassing of volcanic origin in Puerto Naos and La Bombilla, which may have played an important role in controlling the migration and transport of these trace gases towards the surface. Radon and thoron gases activities measurements have revealed to be a worthwhile and non-invasive technique for surface exploration in highly environmental-threatened areas, like La Palma, helping to provide the definition of permeable areas and potential up-flow zones of potential geothermal system structures and permitting an efficient posterior subsurface exploration phase. 
A global englacial temperature database (glenglat)
Authors: Jacquemart Mylène , Welty Ethan
Published: March 2024

Ice temperature is an important characteristic of any glacier. It influences glacier dynamics, subglacial hydrology, glacier retreat behavior, and potential glacier hazards. Additionally, ice temperature can serve as an archive of past air temperature changes and be used for climate reconstructions and validation of thermo-mechanical glacier models. Measuring (deep) ice temperatures, however, is very laborious and costly, and most  ice temperature measurements are hidden away in publications that span almost a century.To overcome the gap between data availability and data need, we have compiled ice temperature data from 132 glaciers in an open-source, version-controlled database available to the scientific community. This global englacial temperature database (glenglat; https://github.com/mjacqu/glenglat) contains temperatures measured in 410 different boreholes in the Americas, Greenland, Eurasia, Africa, and Antarctica between 1938 and 2023. Roughly 20% of all boreholes are known to have reached the glacier bed; the deepest borehole is 743 meters deep; and most measurements are from cold or polythermal glaciers. Data for 369 boreholes were extracted from published literature while data for the remaining 41 boreholes were directly submitted to the authors.The database is structured following the Frictionless Data Tabular Data Package specification. The data are stored as comma-separated-value (CSV) files and the metadata are provided in a single YAML file – text formats which are both human and machine readable. Following a standard structure provides two key advantages: First, upon any change to the data or metadata, the structure and content of the database can automatically be validated using existing software. Second, documentation and data submission templates can be rendered automatically from the machine-readable metadata, which lowers the bar for data maintainers and future contributors. We hope that glenglat can serve many glaciological applications and become the  repository of choice for future ice temperature measurements.
Global distribution of Wind-Wave Causality Index
Authors: Huang Yongxiang , Schmitt Francois
Published: March 2024

When the wind blows over the ocean surface, it generates ripples which grow into wind-waves. These wind-waves can then propagate great distances as swell waves. As a result, measured ocean surface waves are often a combination of local wind-waves and swell waves from distant storms. While it's natural to assume that the wind is the cause and the waves are the effect (one-way causality), the presence of waves can actually modify the ocean surface roughness, altering the wind itself. This creates a feedback loop, introducing mutual causality between the wind and waves.
This study examines this interplay by analyzing wind and wave data simultaneously measured by the CFOSAT satellite. Using the Liang-Kleeman information flow test, a normalized causality index is calculated to quantify the cause-effect relationship. Analysis of a single CFOSAT track confirms the one-way causality assumption, with the wind driving the waves. Further analysis reveals the global distribution of the causality index. Interestingly, higher wind-wave causality (T21) is observed in mid-latitude regions (30°S to 30°N), while it weakens in higher latitudes. Additionally, the wave-wind index remains significantly less than 1, further supporting the dominance of one-way causality in most regions.
 
Ref.
 
Gao, Y. , Schmitt, F.G., Hu,  J.Y. &  Huang, Y.X. (2021) Scaling analysis of the China France Oceanography Satellite along-track wind and wave data. J. Geophys. Res. Oceans, 126:e2020JC017119
Liang,  X. San (2015) Normalizing the causality between time series. Phys. Rev. E 92, 022126.
Gao, Y. , Schmitt, F.G., Hu,  J.Y. &  Huang, Y.X. (2023) Probability-based wind-wave relation. Front. Mar. Sci., 9:108534
Geochemistry of ~1Ga granite and associated mafic rocks from the South Delhi Fold Belt, NW India, and its tectonic significance
Authors: Manna Anirban , Chatterjee Sadhana M. , Roy Alip , Sarkar Ayan K
Published: March 2024

The South Delhi Fold Belt (SDFB) within the northwestern Indian Shield is a Proterozoic NE-SW trending fold belt. The western boundary of the SDFB is defined by the Phulad Shear Zone, formed during a transpression regime around 820-810Ma. Granite rocks of ~1Ga have been documented from the western part of the fold belt and are linked with the formation of the Rodinia Supercontinent. These granites are closely associated with gabbroic rocks. The present study focuses on the geochemistry of these granites and the mafic rocks, as well as their field structure and petrography.
The granites and the mafic rocks are confined to a narrow linear belt along the western part of the fold belt. Detailed field studies reveal that the foliations in the granites, mafic and mylonites within PSZ share a common stress regime and are broadly synchronous. Geochemically these granites are ferroan, calc-alkalic, metaluminous to weakly peraluminous and their classification in granite discrimination diagrams confirms A-type and within plate granite. The mafic rocks exhibit a compositional range from tholeiitic to calc-alkaline, with a trace element ratio resembling enriched mid-oceanic ridge basalt (E-MORB) type magma. The tectonic discrimination diagram suggests rift-related magmatism. Geochemical analysis of these bimodal magmatic compositions in the SDFB, encompassing both mafic rocks and A-type granites are typically associated with areas experiencing extensional tectonics, particularly rift-related magmatism. Integrating field structures, petrography and geochemistry of these granite and the mafic rocks suggests that the ~1Ga granite and the associated mafic rocks formed in an extensional regime and are not directly linked to the collisional assembly of the Rodinia Supercontinent. 
Keywords: South Delhi Fold Belt, Granite, Phulad Shear Zone, Rodinia supercontinent, Extensional regime
A drought monitoring and forecasting system for Switzerland
Authors: Humphrey Vincent , Hüsler Fabia , Bircher-Adrot Simone , Imamovic Adel
Published: March 2024

The intensity and frequency of dry spells in Switzerland have increased in recent years and are likely to increase in the future. Meanwhile, increases in water use and competition between different actors also place a greater pressure on existing water resources. Because drought has been identified as one of the main risks for various economic sectors in Switzerland, a national monitoring and forecasting system is to be established through the joint efforts of three different governmental agencies (federal offices for the environment, meteorology and climatology, and topography). The project also actively involves stakeholders in its development.In this contribution, we introduce the Swiss national drought project with a particular focus on user-centered design, in situ and satellite-based monitoring, and the integration of sub-seasonal forecasts. Results from a user-survey revealed that even though drought is multi-dimensional and affects stakeholders in different ways, one of their primary needs is still a holistic “combined” drought index that can serve as a common ground for discussion and decision-making. Simple, local-scale-focused designs were assessed as the most efficient and useful, whereas designs showcasing nationwide maps or scientific quantities (SPI, etc.) were the least meaningful to educated but not expert users.Further efforts include the creation of a national in situ soil moisture monitoring network with approximately 30 stations, the development of meteorological and agricultural drought products and indices, as well as the establishment of near real time, downscaled, sub-seasonal forecasts derived from existing systems (ECMWF IFS Extended). Integrating these highly heterogeneous data streams into seamless products ranging from historical observations to sub-seasonal forecasts, all within a consistent climatological baseline, is expected to represent both a major technical challenge but also a significant step forward that will greatly benefit downstream user applications. This novel meteorological basis will directly feed into impact-relevant drought indices and hydrological models, with the aim of better supporting an early warning system that has to take into consideration the needs of a very diverse user community, such as hydropower production, navigation, agriculture, forestry, artificial snow production, or ecology.
Automatic regional identification of active and inactive landslides using satellite image analysis
Authors: Tzampoglou Ploutarchos , Loukidis Dimitrios , Tsangaratos Paraskevas , Anastasiades Aristodemos , Valari Elena , Karalis Konstantinos
Published: March 2024

Over the past decades, landslides have significantly affected extensive areas worldwide due to changing environmental conditions and human activities, causing major problems in the built environment and infrastructure and resulting in the loss of human lives and significant financial damages. The island of Cyprus and especially its southwestern part (which constitutes the study area) have experienced the severe impact of landslides due to the unfavorable geological/geotechnical conditions and mountainous geomorphology. According to the data obtained from the Geological Survey Department of Cyprus (GSD), 1842 landslides (active and inactive) of various types have been identified in an area covering 40% (546km2) of the Paphos District (3.4 landslides per km2).Knowledge of the location and extent of existing landslides plays crucial role in the landslide susceptibility and hazard assessment. The primary aim of this research is to develop an algorithm for the automatic detection of landslides at regional scale. This is achieved through application of image recognition technology utilizing the cascade method on the hillshade of a region as produced by ArcGIS. The database of recorded landslides of the GSD was split in a algorithm training dataset and a validation dataset. The study also explores the effect of the resolution of terrain data, expressed by the size of the grid cells. To comprehensively assess landslides, the morphology is classified into three types: active, dormant, and relict. The use of hillshade instead of a raster image of the elevation map was chosen because the latter usually results in relatively minor color variations between adjacent pixels, thus hindering the most striking geomorphological features of landslides, which are the main scarp and the enveloping streams.The results obtained suggest that a hillshade produced using a high-resolution Digital Elevation Model (DEM), i.e. based on elevation contour interval of 1m and a cell size 1 x 1 m (obtained from the Department of Land and Surveys of the Republic of Cyprus), yields better results for landslides with gentle geomorphology (relict). Nonetheless, analysis based on such a high-resolution DEM requires substantial computational resources and time. On the contrary, landslides associated with steeper geomorphologies (active) exhibited optimal performance with a cell size of 2 x 2 m, achieving success rates (80%), for DEMs based on contour intervals of 1m and 5m. In this case, the computational time is significantly reduced.  Depending on the specific landslide types investigated in a particular area, the appropriate processing model can be selected, ultimately leading to significant time savings.This research was funded by the European Commission (Marie Sklodowska-Curie Actions, Hybland-Society and Enterprise panel, Project No.: 101027880).
Regional climate signals in overshoot scenarios
Authors: Pfleiderer Peter , Schleussner Carl-Friedrich , Sillmann Jana
Published: March 2024

Global warming levels are politically relevant targets, and therefore, in public discussion and in climate science, these global warming levels are often taken as a reference for climate states. While the focus on global warming levels is a useful simplification in many cases, it becomes misleading when looking at temperature overshoot (or stabilization) scenarios. In temperature overshoot scenarios, greenhouse gas concentrations are eventually reduced leading to a decrease in global mean temperatures. In such scenarios, lagged effects, feedback mechanisms, and tipping points can result in considerably different climate states after the overshoot as compared to before at the same global warming level.Here we assess to what extent changes in regional climate signals are reversed in the period after peak warming when global mean temperature decreases. We analyze a multi-model ensemble of CMIP6 simulations of two overshoot scenarios, SSP5-34-OS and SSP119. In many regions, climate signals are decoupled from global mean temperatures in the decades after peak warming, leading to differences in regional climate signals between before and after the overshoot at the same global warming level.More dedicated climate simulations of overshoot scenarios would be required to better evaluate how long the influence of the overshoot would affect regional climate signals and to better understand the mechanisms behind these changes. The presented overview of regional climate signals in overshoot scenarios until 2100 already suggests that considerable implications of temperature overshoots for climate impacts are to be expected and that these implications need to be considered for adaptation planning and policy making.
On the evolution of magnetic reconnection in the solar wind
Authors: Fargette Naïs , Eastwood Jonathan , Waters Cara , Lavraud Benoit , Eriksson Stefan , Phan Tai , Oieroset Marit , Stawarz Julia , Franci Luca
Published: March 2024

Magnetic reconnection is a fundamental process in astrophysical plasma, as it enables the dissipation of energy at kinetic scales as well as large-scale reconfiguration of the magnetic topology. In the solar wind, its quantitative role in plasma dynamics and particle energization remains an open question that is starting to come into focus as more missions now probe the inner heliosphere. To more efficiently detect magnetic reconnection in-situ using automated and modern methods is one of the challenges that can bring us closer to understanding the impact of magnetic reconnection on its surrounding magnetized environment.In this presentation, we make use of existing databases to focus on the evolution of magnetic reconnection properties through the heliosphere, using several space missions such as Parker Solar Probe (PSP), Solar Orbiter and Wind. We investigate the properties of small-scale reconnecting current sheets found in the turbulent solar wind as a function of radial distance and plasma source. In parallel, we also make use of PSP-Solar Orbiter alignments to study how the large-scale and high-shear reconnection occurring at the heliospheric current sheet evolves as it propagates in the solar wind. Finally, we emphasize how reconnection has a high impact on coherent structure evolution such as coronal mass ejection erosion or merging.Collectively, these results show that magnetic reconnection is ubiquitous in the solar wind and occurs in a wide variety of settings, with a high impact on its surrounding environment. We discuss how the recent growth of available in-situ spacecraft mission data inside the Earth orbit promises further substantial progress in our understanding of magnetic reconnection occurrence, properties and impact in the solar wind. 
Gas hydrate precipitation and microbial transformation affect the composition of gases migrating through sediments drilled off SW Taiwan
Authors: Pape Thomas , Tu Tzu-Hsuan , Lin Saulwood , Berndt Christian , Wallmann Klaus , Tseng Yiting , Freudenthal Tim , Bohrmann Gerhard
Published: March 2024

Molecular and stable isotopic compositions of light (C1–C3) hydrocarbons in sediments provide information on their formation pathways and postgenetic alterations. In 2018, gas hydrate-bearing sediment cores and borehole logging data were collected with R/V SONNE (cruise SO266) and the seafloor drill rig MARUM-MeBo200 at two sites off SW Taiwan (Bohrmann et al., 2023). The two sites are located on the passive continental margin and on the tectonically active convergent margin in the northern part of the South China Sea (SCS). Geophysical surveys have demonstrated the presence of hydrates at both sites as well as the base of the hydrate stability zone at ∼400 and 450 meters below seafloor (mbsf), respectively (Berndt et al., 2019; Bohrmann et al., 2023). At the passive margin, holes were drilled to a depth of ∼126 mbsf at the southern summit of Formosa Ridge (SSFR, ∼1,140 m water depth). A depth of ~144 mbsf was reached at Four-Way Closure Ridge (FWCR, ~1,320 water depth) on the active margin. Macroscopically, no hydrates were detected in recovered cores from either site, but hydrate-related proxies unequivocally demonstrated the in-situ presence of hydrates. For example, signals in sediment electrical resistivity detected during well logging correlated with anomalies in sediment temperature and pore water chloride concentrations detected in cores. Whereas two hydrate-bearing intervals were identified on SSFR (∼13–39 mbsf, ∼98–120 mbsf), a single interval was found on FWCR (∼65–120 mbsf).Considerable variations in relative hydrocarbon concentrations expressed as C1/(C2–C3) values were observed in gas accumulated in voids in the cores from each site. C1/(C2–C3) values
Spatio-temporal analysis of extreme sea level in the Korean Peninsula
Authors: Yang Jung-A
Published: March 2024

Various countries around the world have been experiencing coastal disasters caused by coastal flooding, and Korean Peninsula is no exception. Most coastal flooding occurs during extreme sea level conditions which is comprised astronomical tides, nontidal residuals, wind wave, and mean sea level. To respond to coastal flooding disasters, it is important to understand the characteristics of extreme sea levels. Therefore, this study analyzed the spatiotemporal patterns of extreme sea levels along the Korean Peninsula and evaluated the effects of the astronomical tides and nontidal residuals represented by storm surges on extreme sea levels among the components constituting extreme sea levels. At this time, when analyzing the impact of the storm surge, it was evaluated whether the storm surge was caused by tropical cyclones or extra-tropical cyclones, and what storm condition were more dangerous in the Korean Peninsula. This study collected observed tidal data from 1979 to 2021 at 48 tide stations which are installed along the coast of the KP and performed a hormonic analysis to distinguish them into astronomical and storm surge components. In this case, storm surges occurring in summer and winter were considered to be caused by tropical cyclones and continental cyclones, respectively. In addition, to more accurately analyze the regional characteristics, the Korea’s coast was divided in the three zones: the East Sea, the West Sea, and the South Sea. As a result of the study, it was found that the extreme sea levels along the Korean Peninsula showed regional differences, and in the case of the south coast, storm surges generated by tropical cyclones were the main drive of extreme sea levels.
Effects of mucilage on soil gas diffusion
Authors: Haupenthal Adrian , Duddek Patrick , Knott Mathilde , Carminati Andrea , Jungkunst Hermann , Kroener Eva , Brüggemann Nicolas
Published: March 2024

Gas exchange in the soil is determined by the size and connectivity of air-filled pores. Root mucilage can partially reduce air-filled pore connectivity and thus reduce gas diffusivity. However, it remains unclear to what extent mucilage affects soil pore connectivity and tortuosity. The aim of this study was to gain a better understanding of gas diffusion processes in the rhizosphere by explaining the geometric alterations of the soil pore space induced by mucilage.We quantified the effect of a root mucilage analogue collected from chia seeds without intrinsic respiratory activity on oxygen diffusion at different water contents during wetting-drying cycles in a diffusion chamber experiment. In addition, we used X-ray computed tomography (CT) imaging to visualize the distribution of air and water in the pore space, and quantified the connectivity of the gas phase. Furthermore, we used environmental scanning electron microscopy (ESEM) to visualize mucilage bridges in the dry soil samples.Quantification of oxygen diffusion showed that mucilage decreased the gas diffusion coefficient in dry soil without affecting air-filled porosity. Without mucilage, a hysteresis in gas diffusion coefficient during a drying-rewetting cycle could be observed for fine sandy soil as well as silt and clay soils. The effect diminished with increasing mucilage content. CT imaging indicated a hysteresis in the connectivity of the gas phase during a drying-rewetting cycle for samples without mucilage. This effect was attenuated with increasing mucilage content. Electron microscopy showed that mucilage forms membrane-like liquid bridges during drying. With increasing mucilage content cylindrical structured are created and at high content interconnected structures are observed throughout the pore space, thereby progressively reducing the connectivity of the gas phase.Our results suggest that the release of mucilage into the soil may be a plant adaptation strategy to balance soil oxygen availability and water content.
Flux-gradient relations: insights from anisotropy analysis
Authors: Mosso Samuele , Calaf Marc , Stiperski Ivana
Published: March 2024

Almost all Earth System Models (ESM) use Monin-Obukhov similarity theory (MOST) to parameterize near surface turbulence. Despite its popularity, MOST has limited applicability and creates high uncertainties in very stable and unstable regimes, over heterogeneous and complex terrain, and is known to incorrectly represent the fluxes at the surface. Including turbulence anisotropy as a non-dimensional scaling parameter has recently proved successful in extending MOST to complex terrain for the scaling of variances and other near surface statistical properties.Here we extend this approach to the scaling of surface gradients of mean wind and temperature, using data from five datasets ranging from flat and homogeneous to slightly complex terrain. The flux-gradient scaling relations exhibit large scatter, especially in unstable conditions where the data’s behavior is unclear. We show that adding turbulence anisotropy into the scaling of gradients allows to drastically reduce the scatter in the relations and develop new and more accurate parametrizations. This is especially true for the flux-gradient relations for wind shear (φm) in unstable conditions, and for temperature gradient (φh) both in unstable and stable regime.The strong dependence of scaled wind speed gradient (φm), on turbulence anisotropy also allows us to finally settle the debate on the free convective regime, which clearly exhibits a -1/3 power law when anisotropy is considered. Whereas the strong dependence of scaled temperature gradients (φh) might explain a poorer performance of that scaling relation in predicting the surface sensible heat flux. Furthermore, the eddy diffusivities for momentum and heat and the turbulent Prandtl number are heavily modulated by anisotropy and the latter vanishes in free convective conditions.These results further accentuate the need to incorporate turbulence anisotropy in boundary layer studies and parametrizations, paving the way for reliable surface parametrizations in ESMs.
UNEP's Methane Alert and Response System (MARS): current status, new developments and case studies
Authors: Irakulis-Loitxate Itziar , Randles Cynthia , Watine-Guiu Marc , Mateo-García Gonzalo , Vaughan Anna , Demeter Meghan , Cifarelli Claudio , Guanter Luis , Maasakkers Joannes D. , Aben Ilse , de Jong Tobias A. , Sharma Shubham , Groshenry Alexis , Peyle Quentin , Benoit Antoine , Caltagirone Manfredi
Published: March 2024

UNEP's Methane Alert and Response System (MARS) is a satellite-based system for the detection and mitigation of methane emissions around the world. As part of the International Methane Emissions Observatory (IMEO), MARS is the first global system connecting satellite methane detection to transparent notification processes intended to trigger mitigation efforts. MARS harnesses state-of-the-art satellite data to identify major emissions, activate its partners to notify relevant stakeholders, and support and track progress toward mitigation.During the year-long pilot phase, more than 600 plumes from the energy sector were detected with high-resolution satellites, and more than a hundred were notified. In December 2023, MARS entered the nominal phase with the launch of a data portal including information about the plumes detected and notified by MARS. In its current form, MARS is focused on the detection of strong point sources (~>1 ton/h) from the oil and gas production sector, but the system is expected to develop and integrate observations from new satellites as they become available and extend to the notification of smaller sources, also from other sectors such as coal mining, waste, or agriculture.In this contribution, we will provide a brief overview of the MARS satellite-based plume detection and monitoring system, with the updates made since the launch of the nominal phase. Furthermore, we will describe some examples of real source detection and notification efforts and discuss the next steps planned for MARS in 2024.
Pantropical tree growth resilience to drought 
Authors: Zuidema Pieter , Babst Flurin , Groenendijk Peter , Rahman Mizanur , Trouet Valerie ,   Tropical Tree-ring Network
Published: March 2024

An increasing incidence and intensity of droughts under anthropogenic climate change jeopardizes the potential of tropical forests and woodlands to capture carbon in woody biomass and act as CO2 sink. A pantropical quantification of drought impacts on tree stem growth is needed to evaluate this risk.We assessed drought impacts in a pantropical network of 477 tree-ring chronologies (>10,000 trees from >150 species and 35 plant families) and found modest stem growth declines (median: 2-4%) during drought years. Growth declines were larger for dry-season than wet-season droughts, specifically for Gymnosperms, and at hotter and more arid sites. Lagged growth reductions during post-drought years were rare. Over half of the growth reduction during drought years was mitigated during wet extreme years.Thus, drought impacts on tropical forest carbon sequestration through stem growth have been small and short-lived. Yet, risks of increasing drought-induced carbon loss is expected to aggravate under climate change, in particular through elevated mortality associated with droughts.
Linking surface tectonics with mantle dynamics using numerical models with data assimilation
Authors: Liu Lijun
Published: March 2024

Quantifying surface manifestations of deep mantle dynamics represents an ultimate goal of Earth science. This task has remained challenging due to uncertain initial and boundary conditions of the 4D nature of Earth evolution. A promising solution is through data assimilation, which substantiates a large number of model parameters with available data, thus greatly reducing model uncertainties. During the past decade, our group has developed both forward-in-time and backward-in-time data assimilation techniques that have greatly improved the quantitative expressions on the linkage between deep mantle dynamics and surface tectonics. Here, I will demonstrate how these data-assimilation models work in practice, and how oceanic subduction and the resulting mantle flow influence the Earth surface through generating 3D lithospheric deformation, intraplate volcanism, and earthquakes. Specific examples include the circum-Pacific plates subduction below continents, and evolution of the cratonic lithosphere.
Decennial infrasonic array analysis of snow-avalanche activity and its weather forcing in Pennine Alps: implications for forecasting
Authors: Belli Giacomo , Gheri Duccio , Marchetti Emanuele , Dellavedova Paola , Durand Nathalie , Bovet Eloise
Published: March 2024

Snow avalanches rank among the deadliest natural hazards in mountain environments worldwide. To date, forecasting is mostly based on measuring meteorological forcing, aiming at assessing the probability of event triggering in a certain area. To validate forecast models, information on avalanche occurrence is critical. However, real-time avalanche detection is still challenging and generally limited to radar or visual surveillance of one or a few known channels; here the need for novel monitoring solutions. In the last decades, infrasound has proven to be one of the most promising tools for real-time detection of avalanches. Indeed, snow avalanches, moving downhill, generate acoustic pressure waves in the air, which can be recorded with an array of infrasonic sensors that allows to detect and characterize the source. However, many difficulties still exist, mostly connected to the discrimination of the avalanche infrasound among the signals radiated by other natural or anthropic infrasonic sources active at the Earth's surface or in the atmosphere.Here we present an analysis of >10 years of data recorded by a small-aperture infrasonic array deployed at an altitude of ~2000 m in Valle d'Aosta (Itay). To detect snow-avalanche events, we develop an algorithm aimed at identifying avalanche signals in the recorded infrasound dataset and calibrated on two avalanche crises occurred in the site. The identified avalanche-type infrasonic signals are then compared to local meteorological data and avalanche bulletins, to test the accuracy of our algorithm. Several clusters of avalanche-type infrasonic signals are identified on days with favourable weather conditions for the triggering of snow avalanches. Our study also allows us to investigate the meteorological forcing of snow avalanches in the Pennine Alps, showing that avalanche storms are induced preferentially as a result of the destabilisation of thick snow accumulations, but also highlighting the importance of weather patterns at seasonal scale.This study was financially supported by the National Recovery and Resilience Plan, Mission 4 Component 2 - Investment 1.4 - NATIONAL CENTER FOR HPC, BIG DATA AND QUANTUM COMPUTING - funded by the European Union - NextGenerationEU - CUPB83C22002830001.