bluuebunny/crossref_metadata_2025 huggingface dataset:
Cattle grazing potentially benefits a key organic carbon producer in a water limited ecosystem
Authors: Pinchevsky Dor , hasson Omri , Osem Yagil , Mandelik Yael , Grünzweig José M.
Published: March 2024

Cattle grazing serves as a principal land management tool in drylands worldwide, substantially affecting major soil properties and processes, such as soil organic carbon, soil moisture, and biotic components. The mechanisms of many of these effects remain elusive, although they hold particular significance, as they play a vital role in determining carbon-, water- and nutrient-related habitat conditions, ultimately affecting the aboveground environment. In addition, trees in drylands serve as ecosystem engineers that can modify soil functionality to a large degree. To examine the combined effects of grazing and trees on soil properties and functioning, a field experiment was carried out in the at the dry edge of the distribution of Quercus calliprinos, a dominant woody species in the eastern Mediterranean region. Large exclosures were installed around Q. calliprinos trees in 2013, preventing cattle from grazing in their vicinity. After eight years (2021), we sampled soil from two habitat types, under the oak canopy and in adjacent herbaceous-dominated space. We found that cattle trampling under the tree canopy accelerated the incorporation of the soil organic and litter layers into the mineral soil, leading to increased soil moisture, microbial activity and nutrient availability. Additionally, beneath the oak canopy, the soil had more soil organic carbon, higher soil moisture, higher availability of some of the nutrients, and the soil detritivore community exhibited an elevated trophic level. Our study showed that cattle grazing has the potential to create fertile soil hotspots under Q. calliprinos, thereby profiting the trees. The study further promotes the idea of Q. calliprinos as a keystone species at the edge of the desert which has a profound impact on the carbon and water relations of the ecosystem.
Road-related macrolitter input to mountain river: the case of the Kamienica Gorczańska stream in Polish Carpathians
Authors: Haska Wojciech , Liro Maciej , Gorczyca Elżbieta
Published: March 2024

Roads are identified by many researchers as important source of waste emissions into the environment [1][2]. Previous works on this topic have analysed spatial distribution of roadside dumping sites as well as composition and amounts of waste they contain [3][4][5]. Recent work has hypothesized that in the case of populated mountain regions, where roads are preferentially located within relatively flat valley bottoms, roads can be an important source of macrolitter to the fluvial system [6]. In this study, we investigate the scale of this phenomenon in the Kamienica Gorczańska catchment in the Polish Carpathians. During fieldwork conducted in 2023, we determined the amount and composition of macrolitter within 103 plots located along various types of roads in the floodplain area of the studied stream. We have distinguished two types roadside macrolitter emission: dispersed and point one. Within plots representing dispersed emission (74) 1759 macrolitter items were reported, including 845 (48.04%) plastic items. Furthermore glass litter had the largest share in the total weight of the colleted waste (56.3%). Moreover, we found that point sources of macrolitter emission (e.g., illegal dumping sites) are most often located along roads surrounded by forests within a distance of up to 100 m from the nearest buildings. Our results highlight the importance of road systems in delivering household waste to the fluvial systems of mountain rivers, suggesting that roadside areas should be more adequately addressed in future waste management strategies.Keywords: road system, macroplastic, mountain stream, household waste, waste management, Kamienica Gorczańska streamThe study was completed within the scope of the Research Project 2020/39/D/ST10/01935 financed by the National Science Center of Poland
Calibrating Displacement Curves to Forecast Forced Migration due to Sea-Level Rise and Tropical Storms
Authors: Lallemant David , Manimaran Sonali , Housset Thannaletchimy , Ponserre Sylvain
Published: March 2024

Coastal communities are expected to be highly exposed to rising sea levels and more frequent and intense tropical storms in the coming decades, with forced migration (or displacement) highly likely in many of these places. The exposure to these hazards is driven not just by climate change, but also by growing populations and rapid urbanisation of coastal cities. However, the extent of forced migration will be highly variable, and will be dependent on pre-existing physical and social vulnerabilities present in each location. Therefore, in order to reliably forecast future forced migration due to sea-level rise and tropical storms, it is necessary to construct spatially explicit displacement curves that link hazard levels to the migratory response of communities. This study has calibrated displacement curves through regression analysis for the Philippines based on historical internal migratory movements due to coastal flooding and tropical storms. The data for calibration was obtained from the Internal Displacement Monitoring Centre and governmental disaster reports, and the calibration was performed at the level 3 administrative boundaries. With the displacement curves, critical thresholds of flood and wind damage, at which point forced migration occurs, are identified. Subsequently, these displacement curves are combined with projections of future sea-levels and tropical storms in order to forecast the forced migration of communities under climate change. The displacement curves can be used by researchers, planners and policymakers to understand the varied migratory response of communities to sea-level rise and its associated hazards. This will allow for effective adaptation plans to be devised in advance in order to manage such forced migration in a manner that allows communities, including vulnerable ones, to relocate and avoid the adverse impacts of a changing climate.
Advanced Meteorite Identification through YOLO Object Detection Algorithms
Authors: Alowais Aisha , Alkhalifa Munya , Subhi Salma , Fernini Ilias
Published: March 2024

This study addresses the challenge of visually identifying meteorites from terrestrial rocks, traditionally a task for experts followed by chemical analysis. We propose a transformative approach using computer vision and machine learning, employing YOLO (You Only Look Once) object detection algorithms (versions 5, 6, 7, and 8), to overcome the bottleneck in expert availability for instantaneous classification. Leveraging a curated selection from the Sharjah Academy for Astronomy, Space Sciences, and Technology (SAASST) unique meteorite collection, we aim to differentiate meteorites from terrestrial rocks based on their surface features and characteristics. The collection comprises a diverse assemblage of approximately 8,000 objects such as iron meteorites, Martian meteorites, tektites, fulgurites, and more. Our methodology includes a comparative analysis of YOLO versions, focusing on precision, recall, and F1 scores to assess each algorithm's adaptability to the unique features of meteoritic material. Preliminary results indicate YOLOv5 as the most efficient compared to its previous versions, achieving a maximum mAP of 0.995 and correctly classifying 93% of test samples. This study aims to determine the optimal YOLO version for enhancing the accuracy and efficiency of meteorite classification. In addition, the selected optimal model will be deployed on a Jetson Nano processor aboard a drone, significantly enhancing onsite meteorite detection capabilities.
CARIOQA-PMP quantum accelerometer simulation
Authors: Schilling Manuel , Forsberg René , Gaaloul Naceur , Gruber Thomas , Lévèque Thomas , Migliaccio Federica , Müller Jürgen , Pereira Dos Santos Franck , Zahzam Nassim ,   CARIOQA-PMP Consortium
Published: March 2024

Satellite gravimetry missions have been providing a global measure of Earth's mass transport for more than 20 years. This provides insights into the solid Earth, cryosphere, ocean dynamics and hydrology. Planned NASA and ESA missions will continue this observation well into the 2030s. They are likely to be based on the technology currently used on the GRACE-FO mission, with some further developments, e.g. in laser ranging technology. A higher temporal and spatial resolution of these gravity field products, currently limited to a few hundred km for 1 cm equivalent water height, is required to meet future user need.One of the limitations is related to instrumental effects, of which the accelerometer is a major aspect. Quantum-based accelerometers are a potential improvement for future missions, but the required technology readiness level (TRL) for key technologies currently precludes deployment. A European pathfinder mission is planned to increase the TRL and demonstrate the technology in space.Under the Horizon Europe funding programme, technology development and maturation are being promoted and "the [Quantum Space Gravimetry] Pathfinder mission shall be launched within this decade, paving the way for the deployment of an EU [Quantum Space Gravimetry] mission within the next decade". Within this framework, the Cold Atom Rubidium Interferometer in Orbit for Quantum Accelerometer - Pathfinder Mission Preparation (CARIOQA-PMP) project is the first step in the design and preparation of the Pathfinder mission. It identifies user needs, prepares simulation tools and develops an engineering model of the quantum accelerometer.This presentation will give an overview of the scientific activities within CARIOQA-PMP, including the link between hardware design and specification, as well as the planning for the Pathfinder mission and a future gravimetry mission. The focus will be on the elements and workflow of the simulation of the quantum sensor on a satellite platform, combining the efforts of the physics and geodesy partners.CARIOQA-PMP is a joint European project, including experts in satellite instrument development (Airbus, Exail SAS, TELETEL, LEONARDO), quantum sensing (LUH, SYRTE, LP2N, LCAR, ONERA, FORTH), space geodesy, Earth sciences and users of gravity field data (LUH, TUM, POLIMI, DTU), as well as in impact maximisation and assessment (PRAXI Network/FORTH, G.A.C. Group), coordinated by the French and German space agencies CNES and DLR under CNES lead. Funded by the European Union
The influence of sub-seasonal to seasonal atmospheric temperature variability on alpine permafrost
Authors: Büeler Dominik , Sharaborova Elizaveta , Pyrina Maria , Lehning Michael , Domeisen Daniela I. V.
Published: March 2024

Alpine permafrost thawing due to climate warming has been rapidly intensifying in the past decades. Since permafrost stabilizes the rock, its thawing has and will become a growing risk for mountainous countries like Switzerland, with potential implications for rockfall magnitude and frequency, mountain infrastructure, mountain ecosystems, and tourism. The long-term trend in the thickening of the active layer and thus the subsidence of the permafrost table in the Swiss Alps due to climate warming is well observed and documented. However, less is known about how sub-seasonal to seasonal variability of atmospheric temperature, in particular individual multi-weekly heatwaves in summer, influence below-ground temperature from year to year. In this interdisciplinary study, we thus explore how atmospheric temperature variability on timescales of days to seasons affects the variability of below-ground temperature and the depth of the permafrost table, measured at various rock borehole stations of the Swiss Permafrost Monitoring Network PERMOS. In addition, we evaluate how well the snowpack and ground surface model SNOWPACK is able to reproduce this relationship. The insights from this analysis will pave the way to couple the SNOWPACK model to sub-seasonal to seasonal weather prediction models, which are increasingly being used to predict the probability of heatwave occurrence several weeks ahead. Such a coupling could allow for a prediction of the evolution of below-ground temperature and of significant permafrost anomalies on an operational basis, and thereby support early warning systems for alpine hazards.
Climatology of surface parameters for the city of Turin using UTOPIA (Italy) land surface model
Authors: Cassardo Claudio , Andreoli Valentina , Bertoni Davide , Lim Sujeong , Manfrin Massimiliano , Park Seon K.
Published: March 2024

While there are several series of daily observations of temperature, precipitation and few other parameters available in many locations in the world, sometimes lasting more than a century, there are much less series of other variables related to the surfae atmospheric layer or underground soil, such as sensible and latent heat fluxes, soil heat flux, soil temperature and moisture in the root layer and below it. This work aims to propose a method to evaluate such parameters at a climatic time scale using a trusted land surface model, taking the variables from the outputs of the simulation and creating a database. In this work, the selected model is the UTOPIA (University of TOrino land surface Process Interaction model in Atmosphere). This technique can be applied in general to each site in which hourly observations of the seven parameters needed for the simulation are available (temperature, humidity, pressure, the two components of the horizontal wind velocity, precipitation and solar radiation or cloudiness). In a preliminary phase, the database will be created on the period 1992-2023, on which we have the availability of hourly measurements carried out at the Department of Physics of the Turin University. In a second phase, we plan to develop a methodology to derive hourly observtions from the existing series of data gathered in the city of Turin, using peculiar methods to interpolate or extrapolate the missing observations of required inputs and to downscale hourly observations from daily observations. This methodology could be tested using the eisting data in the recent climate period.
Enhanced closed-loop underground thermal energy storage systems, using experimental materials via numerical modelling and laboratory analysis
Authors: Franzè Sara , Martelletto Francesca , Dalla Santa Giorgia , Isania Fatemeh , Scotton Paolo , Doretti Luca , Galgaro Antonio
Published: March 2024

Thermal energy storage (TES) is a technology that stocks thermal energy by heating or cooling a storage medium so that the stored energy can be used at a later time for heating and cooling applications and power generation.  TES systems can be divided into three main categories: sensible heat storage (SHS), thermochemical storage (TCS) and latent heat storage (LHS) associated with phase-change materials (PCMs). PCMs are able to release or absorb thermal energy changing their physical state at a quite constant temperature.This work aims to analyse the properties of different PCMs and supporting materials to be used coupled in closed-loop underground thermal energy storage (UTES) system. The physical and thermal properties of different PCMs (from lower to medium – high temperature) and their supporting materials, in particular diatoms, are analysed separately through laboratory analysis and numerical modelling, in order to find out the best material providing high thermal conductivity and capacity, efficiency, durability and low cost. However, research is also open to other types of materials such as graphene, zeolites, carbon nanotube and biochar.Then, the best performances PCM is tested to define the best mix between PCMs (the capacitive part) and diatoms (part that will prevent the leakage during the phase change) under different boundary conditions. With the best mix, combined with cement, cylindrical samples 30 cm in diameter and 1 m in length will be constructed with the patented mixtures with a metallic finned tube inserted within it, to represent a thermal storage mass with a tube inside.This sample will be tested, for low-temperature experiments (below 100 °C), using water as carrier fluid, in a physical model hosted at the UNIPD laboratory constituted by a box (1 m3 volume) that can be filled with dry or saturated loose materials with a metallic tube inserted in the middle to represent the heat exchange between the water flowing in the tube at a certain temperature, and the surrounding material, under different boundary conditions. The experimental device, allows to assess, under controlled conditions, the evolution in time and space of the energetic processes that occur between an heat exchanger and the surrounding ground. A second sample with similar characteristics, on the other hand, will be tested with high temperatures (between 200 °C and 300 °C) using a diathermic oil as heat transfer fluid and will be tested in a different device with a high-temperature heating system. The experimental data obtained will be also used in the construction and calibration process of numerical models by using commercial software (FEFLOW).Finally, the simulation results are expected to identify the best conditions to apply the new conceived mix in a real test site.
High Precision, High Time Cadence Measurements of the Mg II Index of Solar Activity by the Extreme Ultraviolet Sensor aboard the NOAA GOES-R Series
Authors: Snow Martin , McClintock William
Published: March 2024

One of the instruments on the Geostationary Operational Environmental Satellites is the Extreme and Ultraviolet Sensor (EUVS).  Channel C of EUVS measures the Magnesium II core-to-wing ratio with high signal-to-noise ratio at a cadence of three seconds.  This presentation will describe the design of the instrument and give an overview of the data collected so far.  Available data products range from the full-cadence operational data measured every three seconds to science-quality daily averages.  The instrument measures the spectrum of the Sun from 275 to 285 nm with a spectral resolution of 0.1 nm.  It uses a diode array with a sampling width of 0.02 nm, providing five samples per slit width.  The first of these instruments became operational in January 2017 and continues through the present.
Impact of CO2 with impurities on integrity of wellbore cements during CCS 
Authors: van Noort Reinier , Svenningsen Gaute
Published: March 2024

CO2 injected into geological reservoirs for storage will contain a range of impurities dependent on the specifications of the transport and storage operator(s). Such impurities include inert gases such as N2 and Ar, as well as reactive components including SOx, O2, and H2S. Upon injection into a (wet) reservoir, these components will partition between the CO2-phase and the hydrous pore fluid, and some of the reactive species may introduce acidification (in addition to the acidification caused by the CO2 itself), or other chemical reactions. 

In the near-wellbore area, the partitioning impurities can potentially lead to enrichment of water-soluble impurities in the hydrous fluid and corresponding depletion of these impurities in the CO2 plume. Because of this, even low (ppm-level) concentrations of reactive impurities need to be considered with regards to their potential impact on wellbore sealant integrity. As part of the Cementegrity project, we have performed exposure experiments on five different sealant compositions; three of which are based on Ordinary Portland Cement (OPC), one is based on Calcium-Aluminate Cement (CAC) and one is a granite-based geopolymer (GP). Using a purpose-built batch-exposure system, sample cylinders were exposed to water and supercritical CO2 under simulated downhole conditions of 80°C and 8-10 MPa, for up to 16 weeks. The sealant samples were placed at two different levels in each exposure apparatus, so that samples were either exposed to wet supercritical CO2, or to CO2-saturated water. The effect of H2S in the CO2 stream was studied in a second series of experiments, where 2.2 mol% H2S was added to the CO2-phase to which the samples were exposed.

After exposure, the samples were retrieved and cross-sectioned perpendicular to the axial direction, so that the impact of exposure on sealant microstructure and composition could be studied using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). In this paper, we will focus on the different impacts of exposure conditions (wet sc. CO2 vs. CO2-saturated water) as well as the additional impact of H2S.
Changes in the Seasonality of North Atlantic Tropical Cyclones
Authors: Treppiedi Dario , Villarini Gabriele , Noto Leonardo V. , Scoccimarro Enrico , Yang Wenchang , Vecchi Gabriel A.
Published: March 2024

The North Atlantic hurricane season is officially recognized to start on June 1st and end on November 30th. The awareness of this time window is crucial both for federal, state and local agencies as well as the general public to put in place preparation and mitigation efforts to mitigate the impacts of this natural hazard. However, there is an underlying assumption of stationarity in the seasonality of these storms, implying a lack of narrowing or expanding of the hurricane season over the years. Here, we consider the days when tropical cyclones happen (TCdays) to model their seasonality using circular statistics, which is the appropriate modeling framework due to the nature of this quantity. By using mixtures of distributions to model the inter-annual variability of the TCdays, we find an expansion of the tails of the distributions over the period 1966 – 2020 for the North Atlantic basin, leading to a more prolonged hurricane season over the recent decades. These results will be explained in terms of physical drivers, providing insights into the mechanisms that could be responsible for the observed lengthening of the hurricane season.
Drought projections and associated uncertainties over the Arabian Peninsula from CMIP6 models
Authors: Saharwardi Md Saquib , Dasari Hari Prasad , Hassan Waqar Ul , Gandham Harikishan , Pathak Raju , Ashok Karumuri , Hoteit Ibrahim
Published: March 2024

Drought frequency and severity have increased over the water-stressed Arid regions. This research employs multiple CMIP6 global climate models (GCMs) for projecting droughts over the Arabian Peninsula (AP) until the end of the 21st century. We utilized the standardized precipitation index (SPI) and standardized precipitation evapotranspiration index (SPEI) to generate projected future statistics of droughts along with uncertainties assessment from inter-model spread, scenarios, timescale, and methods therein.For this purpose, after a meticulous analysis, we first identify the most suitable GCMs for better representation of AP's drought spatiotemporal pattern over the historical period (1985-2014). Our results indicate an increase in potential evapotranspiration (PET), which dominates simulated drought statistics relative to the precipitation. The projected evolution of the SPEI, which is derived from both precipitation and PET, indicates droughts  consistently increasing from low to high emission scenarios, In contrast, the SPI, owing to relatively-weaker amplification of the precipitation shows a moderately increasing wetness, except for a few northern regions where both indices evolve in agreement The fidelity of the simulated precipitation by many models over the historical period is also relatively poor compared to the PET, which may also be potentially adding to the uncertainties. In general, the principal sources of uncertainty in drought projections evolve from the choices of index, followed by scenarios, and inter-model variability, whereas methods and timescale mostly impact the magnitude of the trend in drought statistics.  
A one-dimensional temperature and age modeling study for selecting the drill site of the oldest ice core near Dome Fuji, Antarctica
Authors: Abe-Ouchi Ayako , Obase Takashi , Saito Fuyuki , Tsutaki Shun , Fujita Shuji , Kawamura Kenji , Motoyama Hideaki
Published: March 2024

The recovery of a new Antarctic ice core spanning the past ∼ 1.5 million years will advance our understanding of climate system dynamics during the Quaternary. Recently, glaciological field surveys have been conducted to select the most suitable core location near Dome Fuji (DF), Antarctica. Specifically, ground-based radar-echo soundings have been used to acquire highly detailed images of bedrock topography and internal ice layers. In this study, we use a one-dimensional (1-D) ice-flow model to compute the temporal evolutions of age and temperature, in which the ice flow is linked with not only transient climate forcing associated with past glacial–interglacial cycles but also transient basal melting diagnosed along the evolving temperature profile. We investigated the influence of ice thickness, accumulation rate, and geothermal heat flux on the age and temperature profiles. The model was constrained by the observed temperature and age profiles reconstructed from the DF ice-core analysis. The results of sensitivity experiments indicate that ice thickness is the most crucial parameter influencing the computed age of the ice because it is critical to the history of basal temperature and basal melting, which can eliminate old ice. The 1-D model was applied to a 54 km long transect in the vicinity of DF and compared with radargram data. We found that the basal age of the ice is mostly controlled by the local ice thickness, demonstrating the importance of high-spatial-resolution surveys of bedrock topography for selecting ice-core drilling sites.
Polycyclic aromatic hydrocarbons (PAHs) and their derivatives in soils developing on coal waste dumps from the Upper Silesia, Poland
Authors: Śmiszek-Lindert Wioleta , Fabiańska Monika , Marynowski Leszek , Barczyk Marzena
Published: March 2024

In southern Poland, the mining industry led to the creation of diverse post-mining waste deposited in dumps. Therefore, it is essential to study and monitor the condition of soils developing there. The soil samples have been collected from the coal waste dump at the Ziemowit Coal Mine in Upper Silesia, Poland. The aim of the research was to determine the extent of soil contamination by polycyclic aromatic hydrocarbons (PAHs) and their derivatives within the soil profile on the dump that was not subjected to thermal phenomena (self-heating).Soil samples were taken at depths of 0, 20, and 40 cm. Powdered samples (ca. 10 g) were extracted using a dichloromethane (DCM)/methanol mixture (1:1 v:v) with an accelerated Dionex ASE 350 solvent extractor. The samples were analysed using GC–MS carried out with an Agilent Technologies 7890A gas chromatograph and Agilent 5975C Network mass spectrometer.The PAHs detected included phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b+k]fluoranthene, benzo[j]fluoranthene, benzo[a]fluoranthene, benzo[a]pyrene, benzo[e]pyrene, perylene, indeno[1,2,3-cd]pyrene, benzo[ghi]perylene, dibenzoanthracenes, and coronene together with their alkyl derivatives in the range of C1-C4. Concentrations of highly carcinogenic PAHs such as benzo[a]pyrene (ca. 0.95 µg/g), benzofluoranthenes (ca. 0.17-3.34 µg/g), and benzo[a]anthracene (ca. 1.70 µg/g) have been determined in all samples. Due to the combined effects of weathering and leaching by waters penetrating the highly permeable dump lighter PAHs were partially or totally removed, among them naphthalene and alkyl naphthalenes up to C3, fluorene, acenaphthene, and acenaphthylene. There are significant differences in compounds absence with sampling depth, i.e. the least leached soils were sampled deepest and closest to the coal waste level, where even C2 naphthalenes were preserved. In PAHs distribution predominate 4- to 5-rings compounds, however also heavier 6-rings PAHs were found.The results show that coal waste dump soil, even there where self-heating is absent, can contain significant amounts of PAHs making it a potential source of contamination spreading, particularly during dry seasons when soil dusting occurs or due to leaching by rain water to nearby water reservoirs.
On the Microgeography of Soil Bacterial Communities
Authors: Bickel Samuel , Or Dani
Published: March 2024

The highly fragmented soil physical environment and the dynamic aqueous phase jointly constrain bacterial life by limiting cell dispersion and modulating diffusion and access to patchy nutrients. A modeling framework that integrates soil hydration conditions with soil organic carbon inputs provides systematic estimates of size distributions and interaction distances among soil bacterial populations. The patterns of bacterial community microgeography provide an important building block for interpreting soil ecological functioning. Experiments and mechanistic modelling show that soil bacterial cluster sizes (measured by counting cell numbers within a community) follow an exponentially truncated power law with parameters (e.g., largest community size) that vary with mean soil water content and carbon inputs across biomes. Theory predicts that similar to human settlement size distributions, tree sizes and other systems in which growth rates are defined by the environment independent of the object size, the resulting bacterial community size distributions is likely to obey the so-called Gibrat’s law. Our results support a potential for generalization using positively skewed distributions of soil bacterial community sizes (e.g., log normal and Gamma). We show that soil bacteria reside in many small communities (with over 90% of soil bacterial communities having less than 100 cells), supported by theoretical predictions of log-normal distribution for non-interacting soil bacterial community sizes with scaling parameters that vary with biome characteristics. We will use estimates of the fraction of the largest bacterial communities where anoxic conditions may develop under prevailing conditions to constrain the number of anoxic hotspots per soil volume.
Advanced retrieval of sulfur dioxide from TROPOMI using COBRA
Authors: Theys Nicolas , Vlietinck Jonas , Yu Huan , De Smedt Isabelle , Fabris Lorenzo , Brenot Hugues , van Gent Jeroen , Niemeijer Sander , Romahn Fabian , Hedelt Pascal , Loyola Diego , Van Roozendael Michel
Published: March 2024

Owing to its high spatial resolution, the TROPOspheric Monitoring Instrument (TROPOMI) launched in 2017 onboard the Sentinel-5 Precursor (S5P) platform provides important information on global volcanic and anthropogenic SO2 emissions, with an unprecedented level of details.In a recent study (Theys et al., 2021), we proposed an approach called Covariance-Based Retrieval Algorithm (COBRA), different from the classical Differential Optical Absorption Spectroscopy (DOAS). Application of COBRA to TROPOMI SO2 column retrievals leads to a significant reduction of the retrieval noise and biases as compared to the TROPOMI operational (DOAS-based) SO2 product. COBRA even reveals new emission sources in long-term averaged SO2 maps.In view of a future operational deployment (planned end 2024), the COBRA SO2 scheme is being implemented as part of the Copernicus S5-P Product Algorithm Laboratory (PAL). In this poster, we give an update of TROPOMI COBRA SO2 results. The latest developments of COBRA S5P-PAL v2 algorithm are presented and discussed. The pre-operational S5P-PAL environment enables a full reprocessing of TROPOMI data. For several examples, we illustrate the COBRA data set for the long-term monitoring of SO2 columns over both anthropogenic and volcanic scenes. Finally, possible future developments of COBRA are discussed. Theys, N., Fioletov, V., Li, C., De Smedt, I., Lerot, C., McLinden, C., Krotkov, N., Griffin, D., Clarisse, L., Hedelt, P., Loyola, D., Wagner, T., Kumar, V., Innes, A., Ribas, R., Hendrick, F., Vlietinck, J., Brenot, H., and Van Roozendael, M.: A Sulfur Dioxide Covariance-Based Retrieval Algorithm (COBRA): application to TROPOMI reveals new emission sources, Atmos. Chem. Phys., 21, 16727–16744, https://doi.org/10.5194/acp-21-16727-2021, 2021. 
Intra-plate volcanism generated by slab-plume interaction: Insights from geodynamic modeling of the Eifel plume and its interaction with the European subducting lithosphere beneath the Alpine subduction zone
Authors: Li Yingying , Steinberger Bernhard , Brune Sascha , Le Breton Eline
Published: March 2024

The Eifel volcanic area in western Germany has been active for tens of million years. Geodetic observations, geochemical analysis and seismological studies all indicate that the source of these long-term volcanic activities is a mantle plume. However, it still remains controversial whether the Eifel plume has a deep origin. This is because the tomography images do not consistently show a continuous plume conduit between the surface and the core-mantle boundary. The Eifel plume is also not associated with any flood basalt province or a clearly age-progressive hotspot track, which is regarded as a key surface feature indicating a deep plume origin. In addition, it has been proposed that the Alpine subduction zone, south-east of the volcanic area, has created a stagnant slab in the mantle transition zone, which might be interacting with the Eifel plume.Based on the previous studies and observations, our two contrasting hypotheses are as follows: (1) The Eifel plume is not rooted in the lower mantle. In this case, subduction beneath the Alps might trigger a return asthenospheric flow and the ascent of an upper-mantle plume, leading to the formation of intraplate volcanism beneath the European plate. (2) The Eifel plume is assisted from an upwelling in the lower mantle. In this case, the subducting plate might tilt the plume conduit and influence the position where volcanism takes place.In this study, we apply the Finite-Element-Method geodynamic modeling code ASPECT to model the ascent of the Eifel plume and its interaction with the subducting slab. We design both slab advancing and slab retreating model set-ups, with and without a plume from the lower mantle beneath the subducting plate. We check whether and under what conditions the Eifel plume will be triggered behind the slab due to slab overturn. Preliminary results show that the return flow induced by subduction can help generate an upper-mantle plume and lead to the formation of volcanism. A series of models are also performed to investigate the effects of mantle viscosity and plume temperature on the plume-slab interaction.
Comparative analysis of effectiveness of I Head, L Head and T Head Groyne
Authors: Priyanka  , Ojha Chandra Shekhar Prasad
Published: March 2024

In the present scenario of changing hydrological patterns due to natural and human-induced reasons, the need for effective management of the river system has become more pronounced than ever. This emphasises the necessity to construct river training structures to mitigate the effect of floods and riverbank erosion. Groynes are river training structures provided to protect and stabilise the riverbanks. Most of the previous studies on these structures focused on studying the flow pattern around I Head groyne in the sand bed. Limited research has been done on L Head Groyne (LHG) and T Head Groyne (THG). This study compares bed morphology and flow pattern around three types of groyne: IHG, LHG, and THG in gravel bed. Experiments were conducted to study and compare the flow characteristics around these groynes under similar flow conditions. The flow depth was maintained at 0.136 m, and the Froude number was kept at 0.61. The maximum scour depth observed for LHG and THG is around 38 % more than that of IHG. The normalized velocity distribution is also compared for the three. It is observed that the reduction in streamwise velocity is maximum for the LHG. The study offers insights into the bank protection capability of the three types of groynes and distinguishes the role of these structures in achieving the different objectives of rivertraining works.
Identification of Potentially Dangerous Glacial Lakes (PDGLs) in the Northwest Himalayas 
Authors: Upadhyaya Anup , Rai Abhishek K.
Published: March 2024

The retreat of glaciers has emerged as a significant threat in recent decades, leading to the emergence and growth of glacial lakes. Many of these lakes are vulnerable to Glacial Lake Outburst Floods (GLOFs) as a result of challenging geotectonic settings and adverse climatic environments. Satellite imageries, Digital Elevation Models (DEMs), seismic and meteorological data were utilized in this study to asses the vulnerability posed by more than 1300 glacial lakes in the Northwest Himalayas (NWH) to a potential GLOF event in the future. We employed the Analytic Hierarchy Processes (AHP) - Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) and AHP - Complex Proportional Assessment of Alternatives (COPRAS) approaches to identify Potentially Dangerous Glacial Lakes (PDGLs), using 15 key conditioning factors.  Over 20 lakes were identified as having very high risk to GLOFs, while more than 130 lakes were classified as being at a high risk. The upper Indus basin possessed the most number of vulnerable lakes, which are at a greater risk of experiencing a probable GLOF event, followed by the Jhelum basin. To authenticate our results, we examined the past GLOFs incidents and our analysis revealed that most of the previous GLOFs are classified as PDGLs falling into either the very high or high risk categories. The findings of this study will provide valuable insights for stakeholders and decision makers enabling them to implement preventive measures to mitigate risks during a potential GLOF event in future.
Urban Areas as a Hybrid System for Methane Emissions to the Atmosphere, Case Study: Cluj-Napoca (ROMANIA)
Authors: Hmoudah Mustafa , Ghiorghiu Eduard , Baciu Calin
Published: March 2024

Methane (CH4), a potent greenhouse gas (GHG) with a relatively short atmospheric lifetime, is important for mitigation actions to bring a near-term climate advantage.Although urban areas cover
Comparison of Atmospheric Large-scale Patterns during two Warming Periods in Greenland in the last 100 years 
Authors: Schalamon Florina Roana , Abermann Jakob , Scher Sebastian , Trügler Andreas , Schöner Wolfgang
Published: March 2024

The air temperature (AT) increased during the Early 20th Century Warming (ETCW), especially in the Arctic, with a similar trend as during the present warming period. This AT increase is observed while investigating the annual AT anomaly of historic observations provided by the Danish Meteorological Institute (DMI) and of the zonal average of Greenland based on reanalysis data (NOAA 20CRv3). 

We define two distinct warming periods (1922–1932 and 1993–2007) for Greenland with a continuous increase in the AT anomaly. The increase is the largest at the northernmost observations in Upernavik and the smallest at the easternmost observations in Tasiilaq. The zonal average trend (Sen's slope) of AT increase in Greenland is 0.1°C/year in both periods, exceeding the global AT trend. Examining the spatial distribution of the AT trend in the reanalysis data during the warming periods reveals a warming hotspot in the sea in front of the West Coast of Greenland, which is more dominant in the second period. Nonetheless, the positive trend is rather homogeneous over Greenland, indicative of large-scale influences rather than localized phenomena. This motivates our study to analyse and compare the structure of atmospheric large-scale patterns (LSP) during these two warming periods. 

To do this, we use an unsupervised self-organizing maps (SOM) algorithm to highlight prevalent LSPs based on the reanalysis of the geopotential height of 500hPa. SOM is an artificial neural network used for clustering data into distinct groups, so-called nodes, by reducing its dimensionality. In the first approach to compare both periods, the frequency of the nodes is evaluated, meaning comparing how often a specific prevalent LSP defined by SOM occurs in the one and the other warming periods. A preliminary result is that there are significant differences in the occurrence of the nodes. Further exploration of the difference in node frequency and setting them into a meteorological context are the primary objectives of this study. 

Additionally, we aim to establish links between LSP and anomalies of atmospheric variables (such as air temperature) to investigate whether similar LSP are accountable for similar deviations. This will deepen our understanding of the atmospheric dynamics during Greenland's warming periods, which affect the cryosphere.  
Using a multi-gas UAS to compare methane and nitrous oxide emissions from highly emitting process steps at wastewater treatment plants 
Authors: Gålfalk Magnus , Bastviken David
Published: March 2024

We present a newly developed UAS and method for sensitive and simultaneous mapping of multiple trace gases including methane (CH4) and nitrous oxide (N2O). Using this UAS capacity, a study of the most highly emitting process steps at several wastewater treatment plants (WWTPs) in Sweden will be presented, where CH4 and N2O emissions are compared, showing the advantage of simultaneously sampling the two gases and the ability allowed by a drone to measure total gas fluxes from extended treatment steps. Usually only CH4 is the main focus of WWTP emission studies, but even relatively small unknown N2O emissions can have a large impact on the climate due to its warming potential being ~10 times higher than CH4 (on a 100-year timescale).The UAS has everything onboard to collect all data needed for the flux calculations, including GPS, a light-weight weather station, sensitive gas sensors, and telemetry data storage. Everything is stored on a customized logger at 1 Hz producing a point cloud from which fluxes of the different gases can be calculated in post-processing.In total 13 WWTPs were included in a one-year measurement campaign using the UAS, targeting mainly sludge treatment and the biological process step. This study exemplifies the capacity and measurement opportunities generated by multi-gas UAS.
Ultra-high spatial resolution mapping of urban vegetation heights with multimodal remote sensing data and deep learning method
Authors: Sun Ying , Xiao Kun , Xin Qinchuan
Published: March 2024

Urban forests are an integral component of urban ecosystems, which play several critical roles in improving the quality of life in cities and towns. Accurate estimation of urban forest canopy height is pivotal for quantifying forest carbon storage and understanding forest ecosystem processes as well as shaping effective forest management police to mitigate global climate change. Although spaceborne or airborne LiDAR can provide the height information, there is often a trade-off between the spatial resolution and spatial coverage. On the synergism of the above two issues, we aim to fuse the multimodal remote sensing data and digital elevation model (DEM) data for ultra-high spatial resolution vegetation canopy height estimation over large urban area. In this study, we introduce a novel deep learning model, ARFCNet, designed for vegetation canopy height mapping employing unmanned aerial vehicle (UAV) imagery, Sentinel data, and DEM data as model inputs. We compare the potential of vegetation canopy height mapping under two strategies: the first involving RGB imagery, Sentinel-1 data, and DEM data with a spatial resolution of 1m, and the second with DEM spatial resolution of 30m. We assessed the model performance and compared with existing canopy height products and ground-based measurements. Results show that the ARFCNet model, under the first strategy, exhibits superior accuracy in estimating vegetation height across different regions, with the R² and RMSE value of 0.98 and 1.33m, respectively. We also mapped the 1-m vegetation canopy height in Guangzhou, China based on ARCFNet model, and compared it with three existing tree height products in Guangzhou (ETHGCH: Lang et al. (2023), GLIGCH: Potapov et al. (2021) and NNGIFCH: Liu et al. (2022)), with R² of 0.72, 0.61, and 0.45, and RMSE of 3.94, 6.04, and 4.81, respectively. In comparison, our ultra-high spatial resolution (1m) vegetation canopy height provides detailed measurements especially in the land cover type of urban land. It holds promise for national or global vegetation heights monitoring, enhancing biomass mapping accuracy, and contributing to carbon neutrality goals.
Meteomatics' Meteodrones as precise alternative to radiosondes: a comparison
Authors: Kobras Melanie , Hammerschmidt Lukas , Kryenbühl Philipp , Guay Brad , Fengler Martin
Published: March 2024

Meteodrones are hexacopters equipped with specific sensors to collect information about temperature, humidity and wind in the lower and middle atmosphere. Besides being substantially more sustainable than radiosondes, Meteodrones have the significant advantage of measuring atmospheric conditions in a vertical profile instead of being deflected from their launching position by wind.For continual verification of data quality, the measurements are compared to co-located standard measurements from radiosondes and evaluated against the World Meteorological Organization's (WMO) observation requirements for high-resolution numerical weather prediction.In addition to a selection of measurement profiles, we present the evaluation of atmospheric data within an extensive 6-month validation period, employing our improved processing algorithms. Therefore, we demonstrate the capability of automatically operated Meteodrones to close the meteorological data gap in the lower atmosphere in order to considerably improve numerical weather forecasts.
Breccia Mechanisms and Hydrothermal Evolution from Both Colombian Emerald Belts
Authors: Betancur Acevedo Camilo Andrés , Kammer Andreas , Garcia Toloza Javier
Published: March 2024

This study presents the conditions of pressure, temperature, and breccia mechanisms that allow the migration of emerald-bearing hydrothermal fluids within the emerald belts of Colombia. Based on detailed petrographic analysis, three different hydrothermal events were determined, establishing a chronological framework that enhances our understanding of geological processes in these emerald belts. The first event is characterized by the high presence of albite, due to an albitization event that altered the rock. The other events are marked by an early stage of carbonatization (second) and a late carbonatization stage (third). After understanding the hydrothermal events, Fermi diad bands were obtained by Raman spectroscopy in fluid inclusions. This approach permits the calculation of the rock pressure using the vibrational modes of the CO2 and their relationship with its density. These analysis was performed in minerals associated with each hydrothermal event. The data obtained from these analyses provides the evolution of the pressure in the whole hydrothermal history. Finally, a fractal analysis applied to breccias from both (western and eastern) emerald belts was performed. This analytical approach aimed to understand the breccia mechanisms throughout the entire hydrothermal history, providing a view of the geological evolution of these emerald belts. Even though both belts present similar events, the western emerald belt reveals higher mechanical energy in comparison with the eastern emerald belt, in which the pressure is generally lower and breccia mechanisms show a higher-intensity corrosive event, the presence of fluidization breccias manifests that the migration of the fragments may be fluid assisted against Halokinesis