bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing Solar Power Plant Efficiency in Arid Regions through a Waterless, Smart Cleaning Robot
Authors: Mohaghegh Mehdi
Published: March 2024

In the pursuit of sustainable energy solutions, solar power plants, particularly in dry and semi-dry areas, face the challenge of dust accumulation on panels, significantly reducing efficiency. Traditional cleaning methods, often reliant on scarce water resources, present an environmental paradox in these water-stressed regions. Our innovative approach involves the development of a smart clearing robot that addresses this issue effectively and sustainably.
This robot utilises advanced digital technologies to both forecast power plant performance and clean solar panels without water usage. Incorporating elements of IoT, Machine Learning, and predictive analytics, the robot provides valuable insights into the plant's operational status while maintaining optimal panel cleanliness through a waterless cleaning mechanism. This approach not only conserves precious water resources but also enhances the overall efficiency and lifespan of solar panels.
Our solution represents a practical application of the Water-Energy-Food (WEF) Nexus, demonstrating how digital innovation can overcome specific challenges while contributing to the broader goals of sustainable development, particularly UN SDGs 6 (Clean Water and Sanitation), 7 (Affordable and Clean Energy), and 13 (Climate Action).
This abstract proposes a pioneering step in utilising digital technology for environmental sustainability, showcasing a synergistic approach to addressing the intertwined challenges of water scarcity and energy efficiency in solar power generation.
Hydrologic Design: Solutions and Communication
Authors: Volpi Elena , Fischer Svenja , Dallan Eleonora , Grimaldi Salvatore , Fiori Aldo , Kochanek Krzysztof , Prieto Cristina
Published: March 2024

Hydrologic design is one of the key tasks of hydrologists and most important for the majority of stakeholders, authorities and practitioners. Generally, hydrologic design consists of the dimensioning of hydro-structures in order to fulfill a pre-specified purpose related to water, e.g. flood protection or water supply. Hydrologic design, therefore, is a key element also for engineering activities beyond the hydrological application, and therefore must be communicated to the interested parties in an appropriate and comprehensive way.In this context, the “Hydrologic Design: Solutions and Communications” working group aims at:1- development of novel, goal-oriented procedures for the design of hydrologic solutions for the societal problems (e.g. extremes like floods and droughts, water management, control of water contamination etc.), bringing the best of the available methods;2- development of novel methods to improve the understanding, characterization, quantification and reduction of uncertainty in hydrology, which will be able to extrapolate the results to data-scarce regions, ungauged catchments or beyond the observation range. The usage of available information from local sources will be improved, by combining different sources of information;3- advances towards more reliable predictions by innovating the combination of the knowledge from deterministic models, probabilistic models and artificial intelligence methods, as well as, analyzing the predicted problem from different angles.We plan to involve the stakeholders into the whole process of acquisition, modeling and/or concluding. Altogether, this will result in a simplified communication of hydrological design and the corresponding uncertainty to stakeholders, local people and authorities and, hence, strengthen the connection between science and practice.
Constraints on the spatial distribution of lunar crustal magnetic sources from orbital magnetic field data
Authors: Oliveira Joana S. , Vervelidou Foteini , Wieczorek Mark A. , Diaz Michelena Marina
Published: March 2024

We know from spacecraft measurements that the crust of the Moon is heterogeneously magnetized. With the exception of a few magnetic anomalies related to craters and swirls, the origin of most of the lunar magnetic anomalies is not understood. Here we evaluate the performance of an inversion methodology, initially conceived to infer the direction of the underlying magnetization from magnetic field measurements, commonly referred to as Parker's method, to elucidate the origin of the magnetic sources by constraining the location and geometry of the underlying magnetization. We assess the performance of the method by conducting a variety of tests, using synthetic magnetized bodies of different geometries. These have been chosen such that they mimic  the main geological structures potentially magnetized within the lunar crust. Our test results show that the Parker method successfully localizes and delineates the two-dimensional surface projection of subsurface three-dimensional magnetized bodies, when certain conditions are fulfilled. In particular, the magnetization should be close to unidirectional, and the magnetic field data should have a higher spatial resolution than the smallest dimension of the magnetized body as well as a high signal-to-noise ratio. As an additional evaluation test, we applied this inversion methodology to two lunar magnetic anomalies that are associated with visible geological features, the Mendel-Rydberg impact basin and the Reiner Gamma swirl. For Mendel-Rydberg,  our analysis shows that the strongest magnetic sources are located within the basin's inner ring in agreement with previous studies showing that during an impact, the crust inside the newly formed crater undergoes demagnetization and potentially remagnetization (if an ambient magnetic field is present). For Reiner Gamma, we found the strongest magnetic sources form a narrow dike-like body that emanates from the center of the Marius Hills volcanic complex. The reason that only one such dike emanating from Marius Hills is magnetized could be linked to an atypical iron-metal composition or to the lunar ambient magnetic field being only intermittently present. Future applications of this method can focus on constraining the origin of the many lunar magnetic anomalies that are not associated with visible geological features.
Quantifying cut-and-fill terrace cycles since the Middle Pleistocene in the Patagonian Steppe, Argentina
Authors: Milanez Fernandes Victoria , Ruby Andreas , McNab Fergus , Niedermann Samuel , Wittmann Hella , Schildgen Taylor
Published: March 2024

The rapid response of Patagonian topography to ice-mass changes, facilitated by the presence of a slab-window, offers an ideal setting for investigating the interplay between surface processes, climate dynamics, and solid Earth rheology. This study focuses on glacio-fluvial terrace sequences of the Río Santa Cruz and Río Shehuen (50ºS), which are fed by glacial meltwater from the Southern Patagonian Icefield and extend for over 200 km along the entire length of the river. Recent research in Patagonia demonstrates that glacio-fluvial gravels from terraces formed in the vicinity of glacier outlets can be reliably correlated to glacial terminations. Thus, these cut-and-fill terrace sequences provide a geomorphic archive uniquely positioned to directly correlate landscape responses with periodic climate forcing. Yet, the spatially extensive preservation of these terraces over 100s of kilometers likely reflects the influence of geodynamic processes active over continental length-scales. Radiometric dating of basalts overlying the oldest terrace generations documents eastward-draining paleo-valleys by 3.2 Ma. New surface exposure-dating of terraces using in situ cosmogenic 10Be and 21Ne reveal onset of net incision at ~1 Ma, with individual terrace ages well-correlated to Patagonian glaciations and global cold periods. We attribute terrace abandonment and incision following glacial cycles to a drop in sediment supply relative to water discharge, likely influenced by the formation of a proglacial lake (Lago Argentino). While the onset of net incision aligns with the decline of the greatest ice extent in Patagonia and the Mid-Pleistocene Transition (MPT), terrace ages and geometry underscore the need to link net incision to regional geodynamic processes. Sub-parallel, vertically offset terrace profiles require a regional base-level fall of 100 m since 1 Ma, while terrace age-elevation relationships show a temporally non-uniform regional incision history. These observations cannot be explained by climatically-forced sediment supply variation, but likely relate to the evolution of the mantle underlying the slab window. Our study highlights the complex interplay between climate-driven factors and regional geodynamics in shaping the fluvial landscape of southern Patagonia.
Soil microbial functional diversity changes under contrasting N2O emission events
Authors: Mattana Stefania , Sabaté Cinta , Tallec Tiphaine , Boland Francois , Manise Tanguy , Heinesch Bernard , Feigenwinter Iris , Turco Fabio , Rautakoski Helena , Lohila Annalea , Guerrieri Rossella , Janssens Ivan , Roland Marilyn , Poblador Sílvia , Magliulo Enzo , Vitale Luca , Wu Liyou , Zhou Jizhong , Peñuelas Josep , Ribas Angela
Published: March 2024

Denitrification, the reduction of nitrogen oxides (NO3-and NO2-) to NO, N2O and, ultimately, to N2 gas in soils, is classified as a microbiologically ‘broad process’ which can be conducted by a wide array of microbes belonging to remote phylogenetic groups. Further, understanding how environmental and management factors drive denitrification is challenging because they are scale-dependent, with large scale drivers affecting denitrification fluxes both directly and through drivers working at detailed small scales. Despite of this, we hypothesized that denitrification processes, although highly complexes due to the multiple processes and environmental conditions involved, they could present a functional convergence at the microbial community level explained by a short list of microbial groups or functions.  On the other hand, different methodological approaches to assess soil microbial diversity are currently used; among them are multiple substrate-induced respiration by MicroResp™, enzymes activities and functional genes abundance and structure by GeoChip 5S microarray. We applied all those methods to study functional diversity in 5 different soils from 5 countries: Finland, Belgium; France, Switzerland and Italy. Studied soils have a wide range of soil pH, organic Carbon and Nitrogen content, and texture. Soils were sampled at Hot Moment and Low flux emission of N2O.   The main objective of this study was to explore possible convergences in terms of functional microbial diversity in contrasting N2O emission events (low emission versus hot moments).  Result showed that MicroResp™ , enzyme activities and GeoChip 5S microarray were reliable ecological indicator to evaluate soil microbial functionality diversity. Results stressed the importance to study soil microbiome at different magnitude of N2O emission with the aim to gain a deeper knowledge of nitrifiers community. Reciprocal relationship of those methodologies, soil proprieties and magnitude of flux emission of N2O are discussed.   
High-resolution mapping of tree mortality in European forests
Authors: Cheng Yan , Oehmcke Stefan , Mosig Clemens , Mirela Beloiu , Kattenborn Teja , Abel Christin , Gominski Dimitri , Nord-Larsen Thomas , Fensholt Rasmus , Horion Stephanie
Published: March 2024

Tree mortality has escalated worldwide in recent years due to climate warming and unprecedented drought events. However, mapping tree mortality across forest ecosystems has not yet been achieved. Aerial photos provide opportunities to reveal the spatial and spectral characteristics of canopy death at local to landscape scales. In this work, we present a deep learning model for mapping tree mortality from aerial photos in various forested ecosystems across Europe. This model builds on a baseline model trained with data on dead tree canopies from California using sub-meter resolution aerial photos and allows the use of various spatial resolutions of the input images (ranging from 10 to 60 cm). By comparing our results to ground observations and/or state-of-the-art forest disturbance and loss products, we will discuss the advantages and limitations of aerial photo-based tree mortality mapping. The proposed framework can be used for large-scale mapping of tree mortality from multi-year aerial photos. The tree mortality maps provide detailed information that can help understand the mechanisms of tree mortality under climate change. Furthermore, aerial photo-based maps can serve as training labels for mapping pixel-level deadwood fractions from satellite images, which enables seamless spatial coverage and could be an essential step towards a global map of tree mortality. 
Transformations of the Electromagnetic Field in Different Frames of Reference and the Applications
Authors: Shen Chao , Ji Yong
Published: March 2024

The transformation of the electromagnetic fields in different frames of reference (wether inertial reference frames or non-inertial reference frames) is the problem frequently met during the electromagnetic measurements in space and the relative analysis. For example, to draw the values of the electromagnetic fields in spacecraft comoving reference frame from the electromagnetic fields measured in the spacecraft rotational reference frame with a reasonable accuracy. Another example is the calculation of the charge density based on the four-point electrostatic field observations of MMS; the present analysis is not very satisfactory and there is still no rigid evaluation on the method applied. However, it is not easy to find a plain and rigid evaluation on the transformation formulas used. In this research, a systematic theoretic investigation has been performed, the universal formulas for the transformation are given and further applied to two actual situations successfully. For space plasmas, the relative velocities of the structures are generally very low and always much less than the speed of light in vacuum, so that the Galillia transformations are applicable. In this study, the Galillia transformations of the electromagnetic fields, the electric potential and magnetic vector potential, and the charge density and current density in different reference frames (wether inertial reference frames or non-inertial reference frames) have been presented and the respective errors are given. The results can find wide applications in space physics. At first, the general formula for the rotational potential of the planets are obtained. Secondly, by using the yielded theoretical results, a strict verification on the deduction of the charge density based on MMS electrostatic fields measurements has been made. It is found that, the Poisson equation is valid because the Coulomb gauge can be used for low-speed motions, and it is enough to draw the charge density from the MMS electrostatic fields measurements with a first order relative error. 
Detecting Geophysical and Geological Signatures of an unknown Fault in Messina Historical Center (Sicily, Southern Italy)
Authors: D’Amico Sebastiano , Pino Paolo , Silvia Scolaro , Torre Antonino , Neri Giancarlo , Presti Debora , Galone Luciano , Orecchio Barbara
Published: March 2024

The analysis of seismic noise measurements indicates an evident shift in the Site Resonant Frequency along a NW-SE axis that crosses the historic center of Messina (Sicily, Southern Italy). This shift implies a clear lateral variation in sediment layers from the southwest to the northeast along the axis. Moreover, it suggests the existence of an unreported fault, differing from the widely accepted NNE-SSW primary structural system attributed to the M 7.1 earthquake of December 28, 1908, the strongest earthquake occurred in the Messina Straits area (southern Italy) in historical times.Further evidence supporting this NW-SE fault is provided by surface geological investigations and comprehensive analyses of morphological and Digital Terrain Model data. While geological observations clearly suggest normal faulting, they do not explicitly reveal any potential strike-slip components. The activity of this NW-SE fault extends back to at least the Middle Pleistocene, as inferred from stratigraphic evidence and borehole data, possibly persisting into the Upper Pleistocene.This newly detected fault warrants more extensive investigation in the near future to ascertain its precise spatial extent and contemporary dynamics, particularly regarding its potential for seismic activity.
Asssessing the impacts of extreme rainfall on urban transport: a complex systems approach
Authors: Ford Alistair , Liu Yimeng , Dawson Richard , Yang Saini
Published: March 2024

Extreme rainfall causes disruption and damage to urban transport networks through flooding, resulting in economic impacts for residents and businesses. The impact of such extreme weather events is the result of a complex interaction between the hazard (shaped by the nature of the rainfall and urban characteristics such as topography and land-use), exposure (the spatial and temporal intersection of the flood footprint with urban infrastructure and assets), and vulnerability (the ability of those assets and their users to cope with the level of flooding). This paper demonstrates a complex systems approach to understand the role of these three components of the impact on urban transport systems by dynamically coupling a hydrodynamic flood model (such as CADDIES 2D or CityCAT) with an agent-based transport model (SUMO). By simulating a range of extreme rainfall events at a range of times of day, the modelling approach allows quantification of the scale of the impact (both direct and indirect) and assessment of adaptation options to reduce the disruption. Inclusion of coupled dynamic models allows the exploration of both hard, including engineered and nature-based approaches, and soft measures such as early warning and home working. This allows for a more-complete cost-benefit analysis of interventions and understanding of their effectiveness.The modelling approach is demonstrated for a range of extreme rainfall events on commuting journeys on the road network in the city of Beijing, China. The results show that whilst grey and green approaches to adaptation can reduce the impact of extreme rainfall on the transport network, the benefits of soft measures, such as demand reduction by increased home working, are greater. Such soft measures also have additional co-benefits for reduction in emissions from transport, and potentially a lower implementation cost. Only by considering these interactions in a complex systems approach can such an assessment be undertaken. 
Experimental Study on the Erodability of Microplastics in Muddy Environments
Authors: Jalon-Rojas Isabel , Lemaire-Coqueugniot Adeline , Gomit Guillaume , Romero-Ramírez Alicia , Jarny Sébastien
Published: March 2024

This study aims to elucidate the erodability behavior of microplastics in muddy environments like lakes, rivers, estuaries, and deltas, quantifying their critical shear stress on muddy sediment beds. Microplastics of diverse compositions, densities, shapes, and sizes were tested in a hydraulic flume with smooth and synthetic cohesive sediment beds. As flow intensity gradually increased, leading to particle mobilization, friction velocities and critical shear stresses were calculated. Initial results on smooth beds reveal that particle shape was a dominant factor in mobilization (sphere > pellet > fiber > sheet), followed by density: for equivalent shapes, denser particles required higher friction velocities for mobilization. Results from tests with different particle sizes and orientations relative to the flow highlight the influence of the exposed surface area: larger surface areas facilitate easier particle mobilization. Comparative experiments on smooth and muddy surfaces revealed higher shear stresses on cohesive sediment beds, attributed to particles sinking. Particle Image Velocimetry (P.I.V.) analysis showcased roughness-induced turbulence, marked by acceleration peaks and depressions, as the primary mechanism facilitating particle detachment from sediment.
Monitoring the surface deformation of an active volcano during a new unrest phase (Askja caldera, central Iceland)
Authors: Oestreicher Nicolas , Ruch Joël , Sæmundsson Þorsteinn , Helgason Jón Kristinn , Serrano Vega Nicolas , Luo Xingjun , Leva Patricia , Maissen Jasmin , Hohl Michael , Aaron Jordan , Manconi Andrea , Geirsson Halldór , Mc Ginnis Daniel , Panza Elisabetta , Chatelain Yohann , Arlaud Frédéric
Published: March 2024

In the summer of 2021, Askja caldera entered a renewed period of unrest, which was marked by a significant uplift of the caldera floor (over 70 cm in 2.5 y) and a slight increase in background seismicity. These indicators suggest the presence of magma rising from depth, potentially heralding an eruption in the months or years ahead. The renewed activity has increased the risk of landslides, particularly along the already unstable slopes of the eastern Öskjuvatn caldera. A major landslide in 2014 triggered a tsunami in the adjacent lake that inundated the lakeshore, reaching several tens of meters above its pre-event surface. To gain a deeper understanding of the unresting phase and its associated hazards that may lead to an eruption, the installation of a comprehensive monitoring system is key.In the summer of 2023, a dense monitoring network was established to address these shortcomings. Three time-lapse cameras were installed to track ground movement along the unstable eastern caldera rim. Three corner reflectors were deployed to capture InSAR data, even during the snow-covered winters. A continuous GNSS instrument was also installed to monitor ground displacement continuously. We also covered the entire Öskjuvatn caldera rim with several drone surveys, in 2020, 2021 and 2023, obtaining high-resolution DEMs and orthomosaics to study ground deformation in the past few years.However, arctic conditions prevail during winter months at Askja caldera. Extensive wind-sculpted ice structures have formed on the stations and prevent using the corner reflectors and time-lapse cameras at their full capacity. Storm- to hurricane-force winds have damaged highly exposed stations on the shoulders of the caldera ring faults. We propose technical improvements for extreme conditions and show preliminary results of our monitoring system. In particular, we show a detailed structural map based on our drone data and extensive field observations, thousands of fractures and other geological features providing a kinematic analysis for different parts of the caldera ring faults cliffs.This collaborative effort between Swiss and Icelandic institutions has established an unprecedented monitoring system for an unresting volcano susceptible to eruptions and landslides. The multi-tools approach offers valuable insights into the behaviour of such calderas and could serve as a model for similar monitoring efforts worldwide.
Isotopic hydrograph separation in the Hydrological Open Air Laboratory, Austria
Authors: Széles Borbála , Holko Ladislav , Parajka Juraj , Stumpp Christine , Stockinger Michael , Komma Jürgen , Rab Gerhard , Wyhlidal Stefan , Schott Katharina , Hogan Patrick , Pavlin Lovrenc , Strauss Peter , Schmaltz Elmar , Blöschl Günter
Published: March 2024

Exploring the contributions of new and old water to runoff during precipitation events in agricultural catchments is essential for understanding runoff generation, solute transport, and soil erosion. The aim of this study was to compare two isotope hydrograph separation methods in the Hydrological Open Air Laboratory (HOAL) in Austria, a 66-ha large experimental catchment dominated by agricultural land use. The classical two-component (IHS) and the ensemble isotope hydrograph separation (EIHS) methods were applied to multiple events in May-October of 2013-2018 using δ18O and δ2H. The new water contributions obtained by the IHS during peak flow were compared with the average new water fraction from the EIHS. The results showed that EIHS provided average new water fractions during peak flows (0.46 for δ18O and 0.47 for δ2H) that were close to the averages obtained by IHS (0.48 for δ18O and 0.50 for δ2H). While the EIHS may be a more robust approach compared to IHS, as it relaxes some of the assumptions of IHS and it gives a reliable average of the new water contribution, the IHS can provide useful information on the new water contribution variability for individual events.
A rotational discontinuity can generate both a foreshock bubble and a hot flow anomaly
Authors: Turc Lucile , Archer Martin , Zhou Hongyang , Kajdic Primoz , Blanco-Cano Xochitl , Pfau-Kempf Yann , Liu Terry , Lin Yu , Omidi Nick , LaMoury Adrian , Lee Sun , Raptis Savvas , Sibeck David , Zhang Hui , Hao Yufei , Silveira Marcos , Wang Boyi , Palmroth Minna
Published: March 2024

Solar wind directional discontinuities can generate transient mesoscale structures upstream of Earth's bow shock, which can have a global impact on the near-Earth environment. Understanding the formation conditions of these transient structures is crucial to evaluate their contribution to solar wind-magnetosphere coupling. Hot flow anomalies (HFAs) are thought to be created only by tangential discontinuities, and develop where the discontinuities intersect the shock. Foreshock bubbles, on the other hand, are associated with both tangential and rotational discontinuities, and are generated before the discontinuities reach the bow shock, as they form due to foreshock suprathermal ions accumulation on the upstream side of the discontinuities. Here we present the results of a global 2D hybrid-Vlasov simulation of the interaction of a rotational discontinuity with near-Earth space performed with the Vlasiator model. As the discontinuity enters the simulation domain, a foreshock bubble forms duskward of the Sun-Earth line, where the foreshock is initially located. Shortly after the discontinuity makes first contact with the bow shock at the subsolar point, we find that a structure with enhanced temperature and strongly deflected flows develops at the intersection of the discontinuity with the bow shock. This structure displays typical features of an HFA. This suggests that both a foreshock bubble and an HFA can be generated concurrently by a single directional discontinuity, and that a rotational discontinuity can lead to HFA formation in some conditions. We compare the ion distribution functions inside the foreshock bubble and the HFA, and find significant solar wind core heating within the HFA, as expected from spacecraft observations. We discuss how the properties of the structures vary spatially and temporally, providing global context to localised spacecraft measurements.
Co-benefits and cost-benefit analysis of energy transition in the power sector in China and India
Authors: Lu Chenxi
Published: March 2024

China and India, two of the world's leading carbon emitters, have pledged to achieve carbon neutrality by mid-century in alignment with the Paris Agreement. Central to this ambition is the electrification of their economies, and both nations have made significant strides in recent years. Yet, a thorough cost-benefit analysis of their energy transition progress and future energy transition pathways remains lacking. Here we adopt nine comprehensive models to assess the region-specific co-benefits related to carbon emission, air pollution, health and employment of energy transition in the power sector in China and India from 2015-2020 and further explore their most cost-effective pathways towards 1.5°C and 2°C scenarios in 2030-2050. We find that although the emissions contributed by the power sector in China and India from 2015 to 2020 resulted in more than 10,000 PM2.5 attributable deaths in 2020, the economic benefit of job creation of new installation of renewable power in 2020 was 68 (95% CI: 56-93) times and 6 (95% CI: 5-7) times than the monetary of health loss. Under the SSP1_RCP2.6 scenario, it will ultimately achieve the largest benefit (monetary health co-benefits) to cost (carbon mitigation cost) ratio for both countries in 2050, and India (14.6 (95% CI: 12.7-16.1) will obtain a larger ratio than that of China (4.1 (95% CI: 3.3-4.7)). We recommend both nations deepen their commitment to power sector transition, prioritizing low-carbon fuels and expanding education and skill training to support the emerging new energy economy.
CAMEMBERT: A Mini-Neptunes General Circulation Model Intercomparison
Authors: Christie Duncan , Schneider Aaron , Charnay Benjamin , Sergeev Denis , Lee Elspeth , Rauscher Emily , Innes Hamish , Malsky Isaac , Carone Ludmila , Steinrueck Maria , Zamyatina Maria , Roman Michael , Mayne Nathan , Noti Pascal , Deitrick Russell , Fauchez Thomas , Komacek Thaddeus , Chen Justin
Published: March 2024

With observatories such as JWST, astronomers are now attempting to better understand the previously inscrutable atmospheres of mini-Neptunes, the smaller and often cooler cousins of the better-studied hot Jupiters. General circulation models (GCMs) are an essential part of the toolset used to improve that understanding, from both the perspective of theoretical investigations and in support of observation. It is only recently, however, that the exoplanet community has begun to benchmark and study the behaviour of our GCMs through intercomparisons, a practice that has been going on in the Earth sciences community for decades. With that in mind, we present CAMEMBERT (Comparing Atmospheric Models of Extrasolar Mini-Neptunes Building and Envisioning Retrievals and Transits), a community effort to compare the many of the GCMs used in studies of mini-Neptunes using common parameters and targets in hopes to better understand differences between our models and to better inform the interpretations of our results. This talk will cover the protocol as well as preliminary insights from the project. CAMEMBERT is a part of the CUISINES meta-framework, which also includes the THAI, SAMOSA, CREME, and MOCHA GCM intercomparisons.
Biochar application on a rainfed barley crop under a climate change scenario does not improve grain yield and quality
Authors: Benavente-Ferraces Iria , Carpio Espinosa María José , Perciun Verónica , Panettieri Marco , García-Gil Juan Carlos , Plaza César
Published: March 2024

Climate change effects on agriculture is already a major threat for global crop production in terms of yields and quality of grains. In particular, sustainability of rainfed agriculture in semiarid regions is severely affected by warming and prolonged drought periods. Exploring new soil amendments such as biochar, which holds in countering climate change effects may be a sustainable method aimed at storing carbon, increasing soil quality and buffering the warming and drought stresses on soil and crops. However, we still need to better understand the effects of biochar application on crop yields, particularly under climate change conditions.To fill this knowledge gap, in a long-term field experiment, we investigated how cumulative biochar addition (20 t ha-1 year-1) under climate change conditions affected a barley crop. Rainout shelters and open-top chambers were set up to simulate a 30% rainfall reduction combined with an increase of 2°C in soil temperature. Unamended soils for both ambient conditions and climate change manipulation were used as a control. Our findings revealed that the barley yield was greatly impacted by climate manipulation reducing the grain yield by 74-81%. However, the application of biochar did not lead to improvements in crop yield under these altered conditions. Moreover, grain quality parameters (specific grain weight and weight of 1000 grains) were not enhanced by the application of biochar nor the simulated climate change conditions.Acknowledgments: this work was supported by the research projects TED2021-132342B-I00 (Spanish MICINN) and TUdi (Horizon 2020, GA 101000224).
A new geoelectric field model for the UK based on long-period magnetotelluric data to assess and forecast ground-based space weather effects
Authors: Huebert Juliane , Beggan Ciaran , Richardson Gemma , Eaton Eliot , Orr Lauren , Kiyan Duygu , Hogg Colin , Clarke Ellen
Published: March 2024

Ground-based impacts of solar activity through the interaction of the Earth’s magnetic field with the solar wind have been classified as a major natural hazard in many mid-high latitude countries. Effects on the ground are closely coupled to local geology due to varying electrical conductivity of different rock types. The conductivity distribution can be estimated from magnetotelluric (MT) measurements, which then is used for the large-scale modelling of the time-varying ground electric field.
This geoelectric field model serves as the input for the impact analysis of Space Weather on ground-based systems such as the high voltage power grid, gas pipelines and railways. Previous efforts in the UK had been based on a thin-sheet approach, but MT data better captures the true conductivity variations in the Earth’s crust and mantle that drive geoelectric fields during space weather activity.  Within the UK-funded SWIMMR programme, we collected long-period MT data at 50 sites with site spacing of 50-70 km in Britain during a field campaign in 2021-23, adding to a few existing legacy data sets. Using a frequency-domain approach and geomagnetic field observations from the UK geomagnetic observatories and variometer sites we can derive models of the geoelectric field during geomagnetic active times. Using the new MT data, we revisit GIC estimates for both historic and modern geomagnetic storms, perform extreme value analysis of both geoelectric fields and GICs, and implement a fast now- and forecasting of ground effects within the SWIMMR framework.
Coupled hydrological-hydrodynamic and data assimilation of the entire river network of the Maroni basin using SWOT river products and other EO missions
Authors: Larnier Kevin , Garambois Pierre-André , Emery Charlotte , Gal Laetitia , Paris Adrien
Published: March 2024

The SWOT mission (NASA, CNES, UK-SA, CSA) launched in December 2022 provides observations of surface of inland water bodies at unprecedented resolution and accuracy. Here we focus on the Level 2 river products (heights and widths at 200m scale) and we assess their usability in creating coupled hydrological-hydrodynamic simulations of large scale basin where in-situ data are sparse. First we use an automated toolchain that generates (i) the mesh and processed input data for the hydrological models SMASH [1] or MGB [2], (ii) the coupling points between the hydrological and the hydrodynamic models, (iii) the mesh for the hydrodynamic 1D model (DassFlow-1D [3]) using either SWOT Level2 river observations of water heights and widths or other EO missions (ICESat-2, Copernicus Sentinels).Then we conduct experiments of data-assimilation of conventionnal altimetry missions (ICESat-2, Sentinel 3), in-situ level heights and SWOT Level 2 river heights in order to correct the unobserved quantities (channel bathymetry and friction coefficient) and the inflow discharges using advanced techniques taking into account correlated effects of control variables and simulated water surface properties. The accuracy obtained using this method is assessed by comparing with the sparse existing in-situ data and in terms of physical consistency of simulated flow signatures with some EO data selected for validation.This methodology and the inference capabilities are illustrated on the Maroni basin (French Guyana) which is the first application of variational data assimilation over a multi-branch river network at basin scale. A large parameter vector composed of spatially distributed friction coefficient and channel bathymetry plus inflow/lateral hydrographs are successfully estimated at various spatio-temporal resolution given data cocktails of varying spatio-temporal densities and informative content. [1] SMASH (Spatially distributed Modelling and ASsimilation for Hydrology) -https://smash.recover.inrae.fr/[2] https://www.ufrgs.br/lsh/mgb/what-is-mgb-iph/[3] https://mathhydronum.insa-toulouse.fr/codes_presentation/pres_dassflow/
Concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans in Kuala Lumpur urban environment and their potential risk to human health
Authors: Latif Mohd Talib , Zain Sharifah Mazrah Syed , Mohd Hanif Norfazrin , Khan Md Firoz , Myilravanan Jivantiran
Published: March 2024

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are persistent organic pollutants that affect human health. This study aimed to quantify the concentrations of 17 PCDDs/PCDFs congeners in ambient air in the urban environment of Kuala Lumpur and their potential risk to humans. PM2.5 and TSP were collected on quartz microfibre using separate high-volume samplers, whereas the gaseous phase and passive samples were captured on polyurethane between December 2021 and October 2022. The results show the Ʃ17PCDD/PCDF concentration in ambient air is 736 ± 375 fg WHO-TEQ m-3, whereas PM2.5, TSP, and gaseous phase concentrations are 223 ± 161 fg WHO-TEQ m-3, 337 ± 213 fg WHO-TEQ m-3 and 507 ± 273 fg WHO-TEQ m-3, respectively. The hepta- and octa-group congeners dominated up to 80% of the Ʃ17PCDDs/PCDFs and are more likely to bind with the particle phase than the gaseous phase. The Ʃ17PCDDs/PCDFs displayed a significant difference between gaseous and particle concentrations (p
A harmonised approach to Calibration and Validation for upcoming Sentinel missions: updates for CO2M and Sentinel-5
Authors: Hayer Catherine , Lang Ruediger , Lindstrot Rasmus , Sierk Bernd , Bojkov Bojan
Published: March 2024

As part of the Copernicus Programme of the European Commission, the European Space Agency (ESA) and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) are expanding the Copernicus Space Component to include additional measurements of atmospheric composition. To support the evaluation of greenhouse gas emission reductions decided during the COP21 meeting in Paris in 2015, new measurements are required with improved accuracy. Measurements from space-borne instruments are a key component of this effort – requiring improvements in both spatial and spectral resolution.The Copernicus missions are Europe’s primary contribution to this effort. The CO2M mission – a constellation of initially 2 platforms – is due to launch at the end of 2026 and will be available to contribute to the global stocktake in 2028 and those beyond. Data from the three instruments on board each platform – CO2I/NO2I, MAP, and CLIM – will be combined to act as a single “hyper-instrument”. NO2 is often co-emitted with CO2 & CH4, so the spectrometer (NO2I) will be used to detect near-surface NO2 plumes; the impact of aerosol pollution on the XCO2 columns will be calculated using the Multi-Angle Polarimeter (MAP); and cloud contamination will be observed and removed via data from the Cloud Imager (CLIM). These data will be used within the CO2 and CH4 retrievals from the CO2I spectrometer to improve the retrievals and allow for a precision of 0.7 ppm and an error of 0.5 ppm for XCO2, and an uncertainty of ~10 ppb for CH4.Sentinel-5 will fly on the EUMETSAT Polar System – Second Generation (EPS-SG) platform, due for launch in 2025. S-5 will be a push-broom hyperspectral UVN spectrometer, with a 7.5 km2 spatial resolution and global daily coverage via a 2670 km wide swath. It will monitor various trace gases, including CH4.Comprehensive calibration and validation analysis during the satellite’s commissioning will be undertaken to ensure they meet the specified requirements, and ongoing monitoring will ensure the instruments continue to comply with the challenging requirements. External data from ground-, airborne-, and satellite-based instruments will be required, covering the whole globe and multiple parts of the EM spectrum. Calibration and Validation techniques are being developed across CO2M and S-5, as well as Sentinel-4 which is also due for launch in 2025. This inter-mission collaboration has been undertaken to reduce duplication of effort and ensure lessons are learned from the commissioning of each mission.Here, we give an update on the current state of planning for the Calibration and Validation operations, and identify gaps in the current provision of external networks, ground-based in particular, so that alternative and additional data sources can be procured.
The impact of the lockdown during the COVID-19 pandemic outbreak on NOx pollution in China, as derived from TROPOMI and variational atmospheric inverse modelling
Authors: Abeed Rimal , Fortems-Cheiney Audrey , Broquet Grégoire , Plauchu Robin , Pison Isabelle , Berchet Antoine , Potier Elise , Dufour Gaëlle , Coman Adriana , Savas Dilek , Siour Guillaume , Eskes Henk , ciais philippe
Published: March 2024

In 2020, China’s response to the COVID-19 breakdown included strict regulations on mobility in several provinces. Multiple studies showed that these measures caused a decrease in the emissions of nitrogen oxides NOx (= NO + NO2). In this study, we exploit the high spatial resolution and coverage of the TROPOMI nitrogen dioxide (NO2) observations, over Eastern China, in order to provide an estimate of this decrease down to the level of provinces. We assimilate these observations in NOx atmospheric inversions for the years 2019 through 2021, based on the variational inversion drivers of the Community Inversion Framework (CIF), coupled to a 0.5° resolution  configuration  of the CHIMERE regional chemistry transport model for the North Chinese Plain region, and of  its adjoint (both including the MELCHIOR-2 chemistry scheme). This framework allows to control the emissions at 0.5° resolution, and then to target emissions at province scale, but also to account for a full chemistry scheme in the atmospheric process. The prior estimate of the anthropogenic emissions for this Bayesian inversion framework is based on a combination of the Carbon-Monitor and CEDS inventories, accounting for the day-to-day variations of these emissions. The corrections of the prior anthropogenic and natural emissions allows to decrease the misfits to the TROPOMI NO2 observation by up to 50%, so that the inverted emissions are highly consistent with these satellite data. Furthermore, the satellite coverage of the domain is good, with more than 60% of the model domain observed 95% of the days. Our results show a decrease in NOx emissions observed in most of Eastern China, during January, February, and March 2020, reaching -40% in February 2020 as compared to 2019. In some Chinese provinces, such as Shanghai, Qinghai, Jiangsu, Hubei and Henan, the reduction in NOx emissions accounted for -38%, -29%, -31%, -36%, and -24% respectively. In North Eastern China, however, our results show an increase in the NOx emissions in three major provinces: Jilin (+11.35% in January 2020), and Liaoning (+16.33% in March 2020). The yearly total emissions of NOx in Eastern China were slightly lower in 2020 than those in 2019, with emissions of 15.58 and 15.76 TgNO2/year, respectively. While in 2021, the total emissions of NOx accounted to16.42 TgNO2/year. We compared the emissions in 2021 to those in 2019, and we found that the levels are higher in most of China, especially in February reaching +45% in the North East, for instance. We show that our results are consistent with other studies that focused on the change in NOx emissions in China, during the COVID-19 lockdown period.
New facilities for high pressure / high temperature experiments on iron alloys at planetary core conditions on the European XFEL
Authors: Merkel Sébastien , Ginestet Hélène ,   EuXFEL 3063 and 2740 community proposals
Published: March 2024

The European XFEL is a new X-ray facility installed near Hamburg, Germany, that provides extremely intense X-ray flashes of less than 50 fs (10-12 s) that can be repeated every 220 ns (10-9 s). The facility, coupled with the High Energy Density (HED) instrument, opens new avenues for experiments on iron alloys under planetary core conditions.The instrument can be coupled with diamond anvil cell experiments. In this case, the X-ray flashes of the XFEL are not only used to measure diffraction images in less that 50 fs, but also to heat the samples and gradually increase sample temperatures every 220 ns, reaching several thousands of degrees at pressures well over a megabar in microseconds. During the 3063 community proposal, we hence tested a new method to explore the phase diagrams of iron alloys at planetary core conditions, inducing phase transformations, melting and microstructural changes in conditions and timeframes that could not be reached in previous experimental systems.The instrument is also compatible with laser-driven shock experiments. DiPOLE 100-X is a world-class laser that can deliver up to 100 J (in 1-omega) and 50 J (in 2-omega) over up to 15 ns pulses, with a repetition rate up to 10 Hz. It is now installed at the High-Energy Density (HED) beamline of the European XFEL. By shining DIPOLE pulses into polymers in the back of our samples, we can generate pressure and temperature conditions well over 100 GPa and several thousands of K and using the European XFEL, we can get in-situ X-ray diffraction! The facility was tested in May 2023 during the 2740 community proposal, involving over 100 scientists from over 40 world-wide institutions.In this presentation, I will hence present these new experiments at the European XFEL and preliminary results that can be obtained. These new measurements will require a lot of development and metrology, however, which are actively pursuing at present.Our work is supported by the ERC HotCores (Grant No 101054994) at the université de Lille.
The impact of plastic pollution in sandy riverbeds
Authors: Russell Catherine , Fernandez Roberto , Parsons Daniel , Pohl Florian
Published: March 2024

Plastic is ubiquitous in the landscape and rivers are increasingly important vectors for its transport. Some riverbeds exhibit bedforms including ripples and dunes, which are well understood, but understanding of plastic in bedforms is in its infancy. In this study, flume tank experiments show that when plastic particles are introduced to sandy riverbeds, bedforms change character and behaviour. We detail i) mechanisms of plastic incorporation and transport in riverbed dunes, ii) the topographic changes that occur on the riverbed, and iii) quantify plastic-induced changes in sand transport downstream. We find that plastic directly affects bed topography and locally increases the proportion of sand suspended in the water column, even at very low concentrations in the sand. In the wider environment, such changes have the potential to impact river ecosystems and wider landscapes. Different plastic types and shapes have different impacts, therefore the classification of plastic ought to be consistent and comparable to sediment. Considering plastic as a sediment, we present a classification scheme, to enable better comparison of plastic to sediment such that we can better understand their interaction with sediment as a sedimentary particle, and therefore why plastics accumulate where they do. This is importantly not just another classification scheme, but a philosophically grounded solution to a long-standing challenge that is set to be of increasing significance in increasingly contaminated contemporary settings. We set the framework to a suite of questions that will aid understanding of plastic routing and accumulation in the rivers and the wider landscape.