bluuebunny/crossref_metadata_2025 huggingface dataset:
A new approach to determine the Top of Atmosphere earth Outgoing Radiation using the Geant4 toolkit
Authors: Boudjella Manal Yasmine , Belbachir Ahmed Hafid , Dib Samy Anis Amine , Meftah Mustapha
Published: February 2023

Monitoring accurately the amount of the incoming solar radiation reaching the ground surface and the outgoing radiation at the top of the atmosphere (TOA) is crucial for quantifying the earth's energy budget as well as for understanding and modelling the climate system and its evolution. In the present investigation, we explore the use of the Geant4 Monte Carlo toolkit and a new reference spectrum SOLAR/SOLSPEC [1] to develop a new model to estimate the spectral distribution of Top of Atmosphere Outgoing Radiation (TOR). The system is implemented in Geant4, a toolkit [2] that simulates the passage of particles through matter. SOLAR-ISS is a high resolution solar spectrum with a mean absolute uncertainty of 1.26% at 1σ. The TOR is estimated for a clear atmosphere and at different air mass (AM). For quality analysis, the performance of this model is examined and evaluated by comparing Geant4 simulation results with those of the DISORT code, where the relative mean difference is less than 7.29% overall the spectral domain from 280 to 3000 nm for a well defined case. The characteristics, such as transmittance and reflectance, etc., of the present and previous results will be analysed and compared to evaluate the performance of Geant4. We can upgrade the current tools with more powerful, efficient, and accurate prototyping. Furthermore, We will consider the design of a graphical user interface for the creation of the simulation input file, this utility will serve as a guideline that helps the user to run a simulation.
Identification of extent and drivers of urbanisation in Ireland: A remote sensing-based approach
Authors: Dash Sonam Sandeep , Basu Bidroha , O'Loughlin Fiachra , Bruen Michael
Published: February 2023

Population growth in conjunction with rapid urbanization and industrialization has put immense pressure on global land use and land cover (LULC) patterns, and subsequently, adversely affect the water quantity and quality of associated water resources. The involved rate of change, spatio-temporal distribution of altered LULC classes, and the corresponding trend of LULC classes are quite challenging to monitor by using the conventional field survey-based approach. This study aims to analyse the changes in urbanization extent over Ireland during the past two decades, i.e., 2001-2021 using remotely sensed imageries. In addition, the extent of urbanization and its association with population growth is studied in detail over 43 spatially distributed study catchments of Ireland. One advantage of using remotely sensed LANDSAT observations include high-resolution spatial data available at a high temporal scale and also that the imagery is available for such long period covering the entire study period. The urbanization mapping is confined to two meteorological seasons, viz., summer and winter of every year analyzed. To aid more reliability in the outcomes of this study, the ACOLITE-based atmospheric correction algorithm has been adopted and the imageries were pre-processed before performing the image classification. The urbanisation trend over the period 2001-2021 revealed that the urban area expansion across the chosen catchments has happened at a rate of 0.13 to 1.14 km2/yr with the highest urban expansion rate is confined to the Dublin region of Ireland during the summer season. Furthermore, a correlation-based approach has been extended to study the drivers of increased urbanization in Ireland. The outcome of the correlation analysis revealed that population growth is the major driver behind increased urbanization and does affect the water resource quality adversely. The developed approach could be well replicated at any global catchment/regional-scale applications to generate essential database and analyse its impact on the water resources of the region of interest.
Climatic imprint in the mechanical properties of ice sheets and its effect on ice flow: Observations fromSouth Pole and EPICA Dome C ice cores
Authors: Martin Carlos , Mulvaney Robert , Conway Howard , Koutnik Michelle , Stevens C. Max , Corr Hugh , Ritz Catherine , Nicholls Keith , Drews Reinhard , Ershadi M. Reza
Published: February 2023

The climatic conditions over ice sheets at the time of snow deposition and compaction imprint distinctive crystallographic properties to the resulting ice. As it gets buried, its macroscopic structure evolves due to vertical compression but retains traces of the climatic imprint that generate distinctive mechanical, thermal and optical properties. Because climate alternates between glacial periods, that are colder and dustier, and interglacial periods, the ice sheets are composed from layers with alternating mechanical properties. Here we compare ice core dust content, crystal orientation fabrics and englacial vertical strain-rates, measured with a phase-sensitive radar (ApRES), at the South Pole and EPICA Dome C ice cores. In agreement with previous observations, we show that ice deposited during glacial periods develops stronger crystal orientation fabrics. In addition, we show that ice deposited during glacial periods is harder in vertical compression and horizontal extension, up to about three times, but softer in shear. These variations in mechanical properties are ignored in ice-flow models but they could be critical for the interpretation of ice core records. Also, we show that the changes in crystal orientation fabrics due to transitions from interglacial to glacial conditions can be detected by radar. This information can be used to constrain age-depth at future ice-core locations.
Constellation of radiation belts survey (CORBES) a COSPAR small satellite constellation survey program for Earth’s radiation belt
Authors: Yang Xiaochao , Dai Lei , Wu Ji , Li Wen , Miyoshi Yoshizumi , Nakamura Rumi , Palmroth Minna , Ebrahimi Mohammad , Deng Li , Li Yulun
Published: February 2023

A COnstellation of Radiation BElt Survey (CORBES) program is proposed by the Sub-Group on Radiation Belt (SGRB) of TGCSS, COSPAR, which is in pursuit of the goal of SGRB, focusing on the implementation of a Small/CubeSats constellation mission for radiation belt exploration. Basing on a general review of the status quo of research on the Earth’s radiation belts dynamics and the unresolved scientiﬁc issues, the scientiﬁc object and observation requirements of CORBES are proposed. The CORBES program is expected to have a constellation of 10-plus small/ CubeSats to take an ultra-fast survey of the Earth’s radiation belt. The general science goal for CORBES is to investigate two groups of physical processes related to the radiation belts: wave-particle interactions and radial transport. This program is an international multilateral cooperation mission, an open and sharing data policy will be implemented. The data set of observations will be shared within the contributors of the constellation and the broad research community at large, then would be of great use for comprehensively understanding the dynamics of magnetospheric energetic populations and developing more standard models of the Earth’s radiation belts. Furthermore, from the application perspective, the ultra-fast survey of the radiation belt could serve as an important facility for monitoring space weather of the Earth as well.
Lagrangian tracer spreading in surface ocean turbulence with ageostrophic dynamics
Authors: Maalouly Michael , Mompean Gilmar , Berti Stefano
Published: February 2023

Ocean submesoscales are characterized by horizontal scales smaller than approximately 10 km that evolve with timescales of O(1) day. Due to their small size and rapid temporal evolution, they are notoriously difficult to measure. In particular, the associated velocity field is not resolved in current satellite altimetry products. At these scales, surface ocean flows are populated by small eddies, and filaments linked with strong gradients of physical properties, such as temperature. Several recent studies indicate that submesoscale fronts are associated with important vertical velocities, thus playing a significant role in vertical transport. On that account, these fine-scale flows are key to the dynamical coupling between the interior and the surface of the ocean, as well as to plankton dynamics and marine ecology. In spite of their importance, the understanding of submesoscale ocean dynamics is still incomplete. In particular, a relevant open question concerns the role played by the ageostrophic components of the surface velocity field that manifest at these scales.By means of numerical simulations, we investigate ocean submesoscale turbulence in the SQG+1 model, which accounts for ageostrophic motions generated at fronts, and which is obtained as a small-Rossby-number approximation of the primitive equations. In the limit of vanishing Rossby number, this system gives surface quasi-geostrophic (SQG) dynamics. In this study, we explore the effect of the ageostrophic flow components on the spreading process of Lagrangian tracer particles on the horizontal. We particularly focus on the characterization of pair-dispersion regimes and particle clustering, as a function of the Rossby number, using different indicators. The observed Lagrangian behaviours are further related to the structure of the underlying turbulent flow. We find that relative dispersion is essentially unaffected by the ageostrophic flow components. However, these components are found to be responsible for (temporary) particle aggregation in cyclonic frontal regions. These results appear interesting for the modelling of submesoscale dynamics and for comparison purposes with the new high-resolution surface current data that will be soon provided by the satellite SWOT.
Plant roots are also hungry for nitrogen in winter
Authors: Andersen Emil , Walz Josefine , LeBlans Niki , Michelsen Anders , Olofsson Johan , Dorrepaal Ellen
Published: February 2023

In the Arctic, much of the year is cold and dark and often snow cover is present. Due to these limitations for active photosynthetic growth during such extended period, plants are challenged. However, while their aboveground parts have a clear seasonal bound by available light, the same may not be the case belowground. Here, temperature, moisture, and nutrient availability may be more important for their activity, which may benefit from a thick snow cover. Recent studies have shown that even after senescence aboveground, plant roots continue to grow in arctic ecosystems, but it is not known for how long into the winter they can remain active in nutrient uptake.To better understand the year-round variation in potential plant N-uptake during a full year in the Arctic, we set up an experiment with non-fertilising 15N-addition (applied as NH4NO3) each month, followed by destructive harvests the month after. 15N-recovery was then measured in aboveground and (attached) belowground parts (separated into plant functional groups), in (unattached) coarse and fine roots, and in microbial biomass as well as in extractable inorganic N. This was done for two sites in northern Sweden differing in precipitation regime and thus snow cover thickness and duration.Overall, our results show that there is clear potential for plants to take up N all year round, with winter potential for N-uptake matching or exceeding summer levels for evergreen and deciduous shrub as well as graminoid species. Shrubs have slightly reduced uptake of 15N during the autumn (beginning of snowfall) and spring (snowmelt). Difference in 15N-uptake between the sites differing in snow depth was smaller than expected, possibly because snow fall was high for both sites during the measurement year causing the snow depth to reach a critical threshold for decoupling soil from air temperature fluctuations.Our results suggest that if N is available in the soil and mobile enough to reach the roots, arctic plants will be able to acquire these resources irrespective of the season. It is therefore important to also consider the period outside of the “active growing” season for understanding plant activity and N-relations. Furthermore, the arctic winters are more sensitive to climate change and increasing temperatures will especially impact this season. Without understanding belowground activity in winter, it is therefore hard to predict future outcome of a changing planet.
Weather forecast downscaling for applications in smart agriculture
Authors: Di Paola Francesco , Gentile Sabrina , Genzano Nicola , Ricciardelli Elisabetta , Romano Filomena , Tramutoli Valerio
Published: February 2023

In the framework of the On Demand Services For Smart Agriculture (OD4SA) project, funded by PO FESR 2014-2020 from Regione Basilicata, Italy, a weather forecast service has been developed, for applications in smart agriculture and precision farming. It is based on the Weather Research and Forecasting (WRF) model and provides a daily 96-hour forecast of temperature and water vapor at 2 m altitude, wind speed and direction at 10 m altitude, atmospheric pressure, solar irradiance, and 1-hour accumulated rainfall, for the Southern Italy. Although encouraging advances in microscale modeling have been achieved in the last decade, the computational costs imposed by the state of the art do not allow for continuous operational forecasting at the sub-kilometer scale, useful for precision farming, especially in southern Italy that is characterized by a complex orography. To overcome this limit, an algorithm based on some Artificial Neural Networks (ANNs) has been developed, by using the WRF Large Eddy Simulation (LES) to build the training database at 240 m spatial resolution. Particular attention was paid to the analysis of the true spatial resolution of the WRF-LES outputs, to the definition of the ANNs topology and to the input selection, from over 250 inputs more than half has been discarded. The preliminary results show RMSE equal on average to 70% of those obtained by using the most common spatial interpolation methods.
Incoherent scatter radar study of D-region gravity wave dynamics above Arecibo
Authors: Zhou Qihou , Li Yanlin , Gong Yun
Published: February 2023

Arecibo incoherent scatter radar was the most powerful radar before its collapse in Dec. 1, 2020. Through its 57 years operation, it collected a large amount of ionospheric back scatter data. Although the radar is best known for studying the E- and F- region, accurate neutral wind measurements in the D-region is unsurpassed. At 75 km altitude, it could measure the neutral wind within an accuracy of 1 m/s with a height resolution of 300 m and time resolution of 1 min. Gravity waves having a period of 10-20 mins were often observed. Those waves typically exhibit a very large vertical wavelength. In this report, we present the gravity wave parameters, including vertical and horizontal wavelengths, momentum fluxes and discuss their propagation characteristics.
The effect of asthenosphere’s rheology on mantle and surface tectonics : the role of composite rheology
Authors: Arnould Maelis , Rolf Tobias , Manjón-Cabeza Córdoba Antonio
Published: February 2023

Earth’s upper mantle rheology controls lithosphere-asthenosphere coupling and thus its surface tectonics. Although rock deformation experiments and seismic anisotropy measurements indicate that dislocation creep can occur in the Earth's uppermost mantle, the role of composite rheology (including both diffusion and dislocation creep) on global-scale mantle dynamics and surface tectonics remains largely unexplored.Here, we investigate the influence of composite rheology on the planform of convection and on the planetary tectonic regime as a function of the lithospheric yield strength in numerical models of mantle convection with plate-like tectonics. We show that the consideration of composite rheology in the upper mantle leads to the self-generation of a discontinuous asthenosphere evolving fast, with a low-viscosity and a maximal thickness that depend on the rheological parameters for diffusion and dislocation creep. In mobile-lid models, the spatio-temporal evolution of the asthenosphere is mainly controlled by the location of slabs and plumes that generate regions of mantle deforming dominantly through dislocation creep. Moreover, the low upper-mantle viscosities caused by composite rheology produce substantial and contrasting effects on surface dynamics. For a strong lithosphere (high yield stress), the large lithosphere-asthenosphere viscosity contrasts promote stagnant-lid convection, while the increase of upper-mantle convective vigor enhances plate mobility for low lithospheric strength (small yield stress). We further show that composite rheology does not facilitate the onset of plate-like behavior at large lithospheric strength due to decoupling between the asthenosphere and the lithosphere.
Contribution of subsidence on relative sea level in Europe
Authors: Thiéblemont Rémi , Le Cozannet Gonéri , Raucoules Daniel , Rohmer Jérémy , Wöppelmann Guy , Calkoen Floris , Nicholls Robert J.
Published: February 2023

While the understanding and modelling of relative sea level rise (SLR) due to ocean density and mass changes have greatly improved over the past few decades, SLR contributions due to vertical ground motions (VGMs) remain a major source of uncertainty. Here, VGMs relate to ground motions that have imprints of a few kilometers, as opposed to broad scale land motion such as Glacial Isostatic Adjustment (GIA). VGMs are caused by processes such as natural resource extraction or the load of anthropogenic infrastructure on recent sediment deposits or natural processes (e.g. sismotectonics, volcanism, landslide), all of which vary in space and time, and can strongly inflate SLR locally.Here, we present a pan-European analysis of relative sea-level changes in Europe considering VGMs based on trends retrieved from the European Ground Motion Service (EGMS). EGMS allows identifying hot spots of robust subsidence along the European coastline such as the north Adriatic coast in Italy, areas such as Palavas (France), Groningen (Netherlands) and many coastal infrastructures such as dikes in La Rochelle (France) where subsidence was not documented earlier. Hence the service delineates where subsidence can have a significant impact to relative sea-level changes in coastal areas. This satisfies a major need from coastal adaptation stakeholders concerned with SLR. EGMS results are complemented and compared with VGMs estimates from permanent Global Navigation Satellite System (GNSS) network stations. The precision of the measurements is discussed: VGMs from GNSS stations derived from 4 different solutions (ULR, NGL, JPL and GFZ) allow accounting for uncertainty in trends estimation techniques. We estimate VGMs residual trends after removing the effect of the GIA from geophysical modelling, but also the effect of contemporary mass redistribution on solid Earth deformation. The results from both GNSS and EGMS suggest that the precision of ground motion velocities can be in the order of a millimetre per year.Overall, these estimates and their uncertainty can be used to produce a new coastal pan-European relative sea-level set of projections that respond to one major user need, namely the identification of areas where sea level rise is amplified by subsidence. However two other user needs remain unachieved: the local attribution of observed sea-level changes to components with a submillimetric per year accuracy and a quantified projection of subsidence, which would at least require subsidence models.    
UAV-based methane emission quantification at a UK landfill site
Authors: Yong Han , Allen Grant , Ricketts Hugo
Published: February 2023

A field campaign using UAV-based measurements to derive methane fluxes from a large landfill site in North Manchester was conducted in the summer of 2022. The system comprises the newly developed ABB lightweight (3kg) Hoverguard greenhouse gas analyser based on the off-Axis Integrated Cavity Output Spectroscopy (with a precision of 0.9 ppb for CH4 at 1 Hz), an on-board TriSonica™ Mini wind sensor and the DJI M600 pro hexacopter.  Fluxes and corresponding flux uncertainties were calculated using the mass-balance method from 6 flight surveys conducted downwind of the active landfill. Accurate and reliable wind measurements sampled from instrumentation onboard rotary-wing UAVs remains a challenge, which was found to dominate flux uncertainty in this study. This study presents a low-cost and repeatable methodology for hotspot methane emission quantification.
Late Paleozoic glaciated landscape in northern Africa as an outstandingly well-preserved analogue to Quaternary deglaciated areas
Authors: Wohlschlägl Ricarda , Kettler Christoph , Le Heron Daniel , Zboray András
Published: February 2023

The Ennedi sandstone plateau in Chad in north-central Africa exposes an outstanding example of an ice stream paleo-landscape that is of Paleozoic age. This assemblage of paleo-glacial structures is of comparable quality to that found in Quaternary deglaciated landscapes. A wide range of exceptionally well-preserved proglacial, ice-marginal and subglacial features are visible due to the absence of vegetation in the desert environment. Paleo-ice stream pathways contain swarms of large-scale glacial lineations distributed over the whole plateau that tell the story of a dying ice sheet during the late Paleozoic. A putative grounding zone wedge within a paleo-ice stream pathway allows the position of the former coastline to be reconstructed as it is assumed that ice streams terminated into a former ocean basin. Based on the convex topography and its position orthogonal to the large-scale glacial lineations, we present the first geomorphological interpretation of a grounding zone wedge in the Paleozoic record. Additionally, a unique system of inverted channel sediments in close proximity to glacial structures might record different phases of meltwater release during ice retreat. In summary, the Ennedi paleo-glacial landscape provides an excellent natural laboratory to understand the spatial relationship between subglacial, ice-marginal and proglacial components of a former ice sheet, with emphasis on exceptional outcrop quality that can be used to further our understanding of some Quaternary glaciated landscapes.
Microbial enzyme activities and use channels during microbial turnover of organic carbon substrates in soil
Authors: Vonhoegen Denise , Yousaf Ubaida , Thiele-Bruhn Sören
Published: February 2023

Recent studies of soil organic matter formation focus on energy and matter fluxes and their linkage to broaden the understanding of the processes and drivers underlying microbial turnover of organic carbon substrates in soil. In this study, which is part of the DriverPool project in the SoilSystems priority program, the energy and mass balances of organic matter turnover are investigated with special reference to the soil microbial community by testing selected hydrocarbon substrates with different properties.In a first incubation experiment the effect of substrate size was investigated by comparing the turnover of glucose (180 Da) and α-1,4-maltoteraose (666.6 Da). We hypothesize that exoenzymatic activity is required for substrates exceeding a size of 600 Da; thus, resulting in a different process type (adaptation-oriented process) compared to the intracellular turnover of  glucose (growth-oriented process). From a batch microcosm experiment, subsamples were collected after different incubation periods to determine microbial pools (biomass, necromass) and the incorporation of the C13-labeled substrates. Enzymatic activity of exoenzymes (α- and β-glucosidase, N-acetyl-glucosaminidase, sulfatase, phosphatase, fungal peroxidase) and endoenzymatic activity (dehydrogenase) were assessed to elaborate the understanding of metabolic pathways. To analyze shifts in the microbial community and to identify a bacterial- or fungal-dominated use channel for each substrate, substrate induced alteration in phospholipid fatty acid (PLFA) patterns of the harvested samples will be studied as well. First results show differences in enzyme activity pattern for glucose and maltotetraose.
The Role of Teachers’ Competencies in Education of Sustainable Development
Authors: Aceska Natalija
Published: February 2023

The education of sustainable development (ESD) in the curricula claims to foster students‘ability to take part in promoting sustainable development. A number of studies show that the implementation of sustainable development is highly demanding for teachers and requires specific knowledge and abilities. Hence, it is important to determine what competencies teachers need in order to develop and implement education of sustainable development and to attain specific educational goals with their students. ESD requires a specific and more constructive focus on teaching, which raises the question of building corresponding competencies in teachers’ education. Teachers have to gain the insight through constructivism, that acquiring competencies is a self-steered and active process, which can be fostered but not created. In this paper we present results from a research carried out in primary schools in North Macedonia aiming to assess the level of teachers’ competencies with respect to ESD. The objective of the study is to explore the perceptions and views on teachers’ competencies in relation to education of sustainable development. For this purpose as research instrument we have designed and applied an online questionnaire on separate samples of teachers and students. The gained results from the empirical analysis are used to promote the awareness amongst teachers about the development of ESD competencies in order to become more alive and integrated within the existing education curriculum.Keywords: education for sustainable development (ESD), teachers’ competencies.
A flexible, scalable, cloud-native framework for geospatial modelling
Authors: Edwards Blair , Fraccaro Paolo , Stoyanov Nikola , Jones Anne , Butt Junaid , Kuehnert Julian , Taylor Andrew , Garikipati Bhargav
Published: February 2023

Understanding and quantifying the risk of the physical impacts of climate change and their subsequent consequences have crucial importance in the changing climate for both businesses and society more widely. Historically, modelling workflows to assess such impacts have been bespoke and constrained by the data they can consume, the compute infrastructure, the expertise required to run them and the specific ways they are configured. Here we present, a cloud-native modelling framework for running geospatial models in a flexible, scalable, configurable, user-friendly manner. This enables models (physical or ML/AI) to be rapidly onboarded and composed into workflows. These workflows can be flexible, dynamic and extendable, running as for historical events, or as forecast ensembles, with varying data inputs, or extended to model impact in the real world (e.g. for example to infrastructure and populations). The framework supports the streamlined training and deployment of AI models, which can be seamlessly integrated with physical models to create hybrid workflows. We demonstrate the application and features of the framework for the examples of flooding and wildfire.
Atmospheric drying across Europe is unprecedented in a pre-industrial context
Authors: Treydte Kerstin ,   67 co-authors
Published: February 2023

Vapour pressure deficit (VPD) represents the desiccation strength of the atmosphere, fundamentally impacting evapotranspiration, ecosystem functioning and vegetation productivity. Its spatial patterns and long-term changes under natural versus human-induced climate change are poorly understood but are essential for predicting its future ecological and socio-economic effects, e.g., on crop yield, bioclimatic comfort or wildfires. We combine regional reconstructions of pre-industrial summer VPD variability from a European tree-ring oxygen-isotope network with excellent climate sensitivity with observations and Earth System Model simulations. We demonstrate a recent human-induced intensification of atmospheric drying across Europe that exceeds natural variability specifically in the Alps and Pyrenees, but also in western, central and southern Europe. A less distinct increase occurs in Fennoscandia. This VPD increase may cause an enhanced risk of tree mortality, forest decline and yield reductionsevenin the temperate lowland regions of Europe, particularly when considering the extreme drought events in the recent years.
Snow cover estimation by deep-learning segmentic segmentation of radar images based on optical image references
Authors: Montginoux Mathias , Weissgerber Flora , Monteil Céline , Girard Alexandre
Published: February 2023

In order to improve the forecasting of hydraulic production, EDF uses optical satellite images to evaluate the snow cover [1]. These images are acquired daily by the MODIS instrument of the Terra satellite and provide a snow product through the Normalized Difference Snow Index (NDSI). However, part of the information on the snow cover is lost due to clouds. To complete those gaps, radar satellite images can be interesting because it does not depend on weather conditions.Dry snow and wet snow have different SAR signature. Wet snow can be detected since its backscatter decreases [2]. Dry snow detection is more challenging. It may be performed with a polarimetric approach [3], and the snow depth (SD) can be estimated using optical images as auxiliary inputs [4]. In this work, wet snow was detected and SD was estimated over the Guil basin in the Alps (420 km²) for the years 2018 and 2019 on three relative orbits of Sentinel-1: the D66 (descending, 87 images), A88 (ascending, 119 images), and D139 (descending, 90 images). The results show an accumulation of snow in autumn on the SD and a peak of snowmelt in spring on the detection of wet snow.Then we propose to detect the snow from SAR images using a convolutional neural network trained with optical images from MODIS as labels. For the dataset, a smaller area is chosen around Abriès (of approximately 59km²) and we select 36 images for each of the three orbits to study the winter 2018-2019. A binary semantic segmentation is computed from two SAR inputs: Rwet from [2], and Rdry a polarimetric ratio inspired from [3]. The trained model, called SESAR U-net, gives a snow detection with an overall accuracy of 80% for our test set. This low accuracy result can be explained by the fact that MODIS images have a resolution 25 to 100 times coarser than the SAR images, which hinder both the training and the evaluation of the model. Further works will consider the uncertainty of the MODIS label in the loss computation to improve the training.[1] M. Le Lay et al., “Use of snow data in a hydrological distributed model: different approaches for improving model realism,” in EGU General Assembly Conference Abstracts, EGU General Assembly Conference Abstracts, p. 14545, Apr. 2018.[2] T. Nagler et al., “Advancements for snowmelt monitoring by means of sentinel-1 sar,” Remote Sensing, vol. 8, 04 2016.[3] A. Reppucci et al., “Estimation of snow-pack characteristics by means of polarimetric SAR data,” in Remote Sensing for Agriculture, Ecosystems, and Hydrology XIV (C. M. U. Neale and A. Maltese, eds.), vol. 8531, p. 85310Z, International Society for Optics and Photonics, SPIE, 2012.[4] H. Lievens et al., “Snow depth variability in the Northern Hemisphere mountains observed from space,” Nature Communications, vol. 10, p. 4629, Dec. 2019.
Drilling engineering experience gained from MD-BTES construction phase of SKEWS demo-site
Authors: Landau Matthias , Seib Lukas , Bossennec Claire , Handke Heiko , Muhl Jürgen , Stumpf Jürgen , Schindler Uwe , Sass Ingo
Published: February 2023

As a result of the current energy crisis triggered by war and increasing shortage of resources, renewable energy sources are becoming increasingly important. The storage of heat from fluctuating energy sources is an essential component for independent and base-load capable energy supply. A promising technology are medium-deep geothermal storage systems, which store excess heat in the crystalline subsurface and offer significant advantages over near-surface geothermal storage systems. At the Lichtwiese campus of the Technical University of Darmstadt, the world's first medium-deep research geothermal storage system was constructed in the crystalline bedrock with three 750 m deep boreholes with a distance of approx. 8.6 m (research project SKEWS, project administrator Jülich, funding code 03EE4030A). The outer casing of the coaxial system has a diameter of 7", on which an attached glass fiber cable records temperature and strain measurements. Research operations began in the spring of 2023, which consists of an initial enhanced Geothermal Response Test (eGRT) followed by five heating and cooling phases.The experience and knowledge acquired are intended to demonstrate the basic construction and operational feasibility of such storage systems, as well as to be used as a basis for the planning, dimensioning, construction and costing of future projects.With the current project status, it has already been possible to evaluate the processes of the drilling phase and their effects on the drilling operation. The encountering of deviating geological and hydrogeological conditions to the prognosis from the planning phase required, among other things, the change of the drilling technique from water hammer to rotary drilling with a clay-fresh-water fluid and accordingly also affected the verticality of the drillings. Based on the detailed drilling data recorded and the geological conditions explored, the drilling phase of the storage system could be evaluated in terms of its material usage, drilling accuracy, costs and energy consumption.
We invent pictograms
Authors: Ugrenović Beba , Kovačić Biljana
Published: February 2023

A pictogram is an image on a label that contains a warning symbol and special colors to provide information about the harmfulness of substances or mixtures, or how these substances can affect us or the environment. The CLP Regulation introduced a new system for the classification and labeling of hazardous chemicals in the European Union, and it has also been adopted in Serbia. The pictograms have changed and are now in line with the Globally Harmonized System of the United Nations               In the seventh grade of elementary school, when students are introduced to chemistry, the new subject they are studying, it is planned to learn basic pictograms in the part of curriculum called  ​​the Chemical Laboratory.               In class, students are introduced to the concept of pictograms. Then the students are presented with basic pictograms that they may encounter in their everyday life. After that, students should find pictograms on the packaging of chemical products used in the household and food packaging, recognize them and determine their meaning. After that, students are given the task of designing a pictogram for a topic of their choice.            This activity can be carried out with different age groups of students with adjustments to the teaching content.
Quantifying in-situ decay-rates of faecal indicators and pathogenic viruses in a river section in Germany.
Authors: Zamzow Malte , Seise Wolfgang , Selinka Hans-Christoph , Schumacher Frank
Published: February 2023

For assessing the health risk at recreational waters resulting from wastewater discharges from urban catchments, knowledge about the dynamics of the ratio between faecal indicator bacteria and pathogenic viruses is essential. Differences in wastewater concentrations, decay rates, and relevant exposure concentrations may influence how reliable concentrations of faecal indicator bacteria truly reflect existing health risk. Full-scale experiments on decay rates of pathogenic viruses in natural surface waters, especially fresh waters, are largely missing.In the present study, we quantified the decay rates of faecal indicator bacteria and pathogenic viruses in a natural surface water. To this end, we performed two Lagrangian sampling campaigns after combined sewer overflows (CSO) along a river section in Berlin, Germany. During the campaigns the same body of contaminated water was resampled while travelling through the city. Organic micro-pollutants (Gabapentine, Acesulfame), and inorganic ions (Cl-, SO42-) were analysed to function as conservative tracer substances. Wastewater and stormwater amounts were estimated in each sample. Furthermore, all samples were analysed for humane Norovirus GII, Adenovirus 40/41, somatic coliphages, f-specifc coliphages, intestinale enterococci, and E.coli. Decay rates were derived by relating the pathogens to the estimated fraction of wastewater. The observation time was 5 and 2 days for the first and second CSO event, depending on the flow of the river. Decay rates indicate a significant variability between organisms but also between sampling campaigns as a result of different physical-chemical conditions. While the oxygen was completely consumed in the wastewater plume of the first event, this was not the case during the second event, which still allowed pathogen removal by grazing of heterotrophic zooplankton. Our results contribute to the general understanding of pathogens and faecal indicators in surface waters.
Implications of optimal resource allocation in soil microorganisms
Authors: Schwarz Erik , Belyazid Salim , Manzoni Stefano
Published: February 2023

Soil microbes are key players in the cycling of soil organic carbon. In the complex soil system, microbes are faced with multiple stresses and trade-offs. In order to build biomass and proliferate, microbes have to mine accessible substrate and simultaneously have to survive abiotic stresses such as dry conditions. How they allocate carbon to the production of microbial biomass, extracellular enzymes, or biomolecules that help resist abiotic stresses is an important control of soil organic carbon fate. High carbon use efficiency fuels the build-up of microbial necromass, while increased production of exoenzymes might accelerate the breakdown of particulate organic matter. Production of additional biopolymers needed to sustain metabolic activity under stress – e.g., the production of osmolytes for maintaining turgor pressure in drying soils – poses an additional carbon cost that trades-off with the production of biomass and extracellular enzymes. Here we propose a conceptual model of soil carbon cycling with an explicit representation of these microbial allocation trade-offs. The model resolves physical processes such as saturation dependent substrate diffusion and is formulated at steady-state. It is based on the premise that microbes are optimally adapted to the environment they inhabit – meaning that the allocation trade-offs between the production of biomass, extracellular enzymes, and biomolecular stress response are adapted to maximize the microbial growth rate under these conditions. Using this conceptual model, we investigate how microbial allocation traits (fraction of carbon taken up and allocated to new biomass, extracellular enzymes, or osmolytes) might vary over a range of environmental conditions. Optimal allocation of carbon leads to increased investment in extracellular enzymes when carbon is scarce, and to progressively higher investment in osmolytes in drier conditions. While these trends are somewhat expected, the model predicts (rather than prescribing) the sensitivity of these allocation traits to changes in soil moisture and available carbon as a consequence of the optimality assumption. We conclude by exploring what implications these results might have for soil organic carbon fate.
Decay of the perturbations induced by a horizontal cylinder across an open-channel flow
Authors: Fernandez Théo , Schnauder Ingo , Eiff Olivier , Blanckaert Koen
Published: February 2023

A laboratory study is reported on the flow perturbations induced by a cylinder across an open-channel flow at a subcritical Reynolds number of ReD = 104 (based on the cylinder diameter). Inspired by field measurements on the Plizska River, Poland (Blanckaert et al., 2014) the investigated configuration is representative of large wood trunks that traverse a river.The flow perturbation induced by cylinders has been abundantly investigated in infinite unbounded configurations. Cylinders placed in a bottom boundary layer, such as found in rivers, have hardly been investigated. Previous investigations have demonstrated the importance of different parameters such as the cylinder-based Reynolds number ReD , the gap ratio Gb, defined as the ratio between the distance from the flume bed to the lower edge of the cylinder and the cylinder diameter D, the blockage ratio Br, defined as the ratio between D and the boundary layer thickness, and the boundary layer turbulence. However, these studies mainly focused on the frequency of the vortex shedding, characterized by the Strouhal number St and not on the characteristics of the wake.Thus, a first aim of the present study is to analyze the flow characteristics in the wake of the cylinder, such as the half-width of the wake L0 , the velocity deficit Us , the decay of the perturbations in the streamwise velocity ū, turbulent kinetic energy k and Reynolds stresses.A second aim is to analyze the effect of the bed boundary layer on the perturbations induced by the cylinder, and the effect of the latter on the bed boundary layer. This is important as these mutual interactions can have implications on the bed morphology, fluxes of matter including wake retention and hyporheic exchange and stream habitats in general.The study reveals that important differences exist between the flow perturbations in unbounded and bounded configurations. In a bounded environment, the wake half-width L0 increases at a slower rate along the flow direction and is limited by the boundaries (the free-surface and the bed). Moreover, a faster recovery of the streamwise velocity ū and a faster decay of the velocity deficit Us were observed. These differences with the unbounded case are due to the confinement of the wake and the blockage created by the cylinder. Furthermore, the turbulence generated by the interaction of the wake and the boundary layer, as well as the ambient turbulence also have an impact on these differences. Blanckaert, K., Han, R., Pilotto, F., and Pusch, M. (2014). Effects of Large Wood on Morphology, Flow and Turbulence in a Lowland River. In International Conference on Fluvial Hydraulics, River Flow 2014, pages 2493–25
Neural network surrogate models for multiple scattering: Application to OMPS LP simulations
Authors: Himes Michael , Kramarova Natalya , Zhu Tong , Mok Jungbin , Bandel Matthew , Fasnacht Zachary , Loughman Robert
Published: February 2023

Retrieving ozone from limb measurements necessitates the modeling of scattered light through the atmosphere.  However, accurately modeling multiple scattering (MS) during retrieval requires excessive computational resources; consequently, operational retrieval models employ approximations in lieu of the full MS calculation.  Here we consider an alternative MS approximation method, where we use radiative transfer (RT) simulations to train neural network models to predict the MS radiances.  We present our findings regarding the best-performing network hyperparameters, normalization schemes, and input/output data structures.  Using RT calculations based on measurements by the Ozone Mapping and Profiling Suite's Limb Profiler (OMPS/LP), we compare the accuracy of these neural-network models with both the full MS calculation as well as the current MS approximation methods utilized during OMPS/LP retrievals.
First Quantitative Assessment of Anthropogenic Methane Sources Investigated by the CHARM-F Lidar during the CoMet 2.0 Arctic Airborne Campaign
Authors: Fruck Christian , Quatrevalet Mathieu , Fix Andreas , Wolff Sebastian , Wirth Martin , Ehret Gerhard
Published: February 2023

The CoMet 2.0 Arctic airborne greenhouse gas measurement campaign took place over Canada in Summer of 2022. For the campaign, the German research aircraft HALO has been equipped with various instruments for remote-sensing and in-situ measurements of CO2 and CH4 and flown over target areas with potential sources of greenhouse gases, either natural (wetlands, thawing permafrost, etc.) or anthropogenic (oil and gas drilling sites, oil-sand mining, open-pit coal mines, landfills as well as biomass-burning in forest fires). With the city of Edmonton, Alberta as campaign base, a variety of sources of methane released due to human activity and adding substantially to the Canadian anthropogenic CH4 budget were conveniently within reach for our measurements.This presentation focuses on a selection of anthropogenic sources of CH4 in Canada as well as the Valdemingómez and Pinto landfill sites near Madrid, which were targeted during a test flight. We show first results of the evaluation of active remote-sensing measurements that were conducted with DLR's CHARM-F lidar system. By using the Integrated-Path Differential-Absorption (IPDA)-lidar technique, CHARM-F enables measurements of total column concentrations of methane and carbon dioxide along flight tracks. After further adding wind information from auxiliary measurements or models, emission fluxes from localized sources can be estimated. We will highlight the top emitters in terms of estimated emission rate of CH4 (in the 10kt/year range). Those are likely the most promising candidates for mitigation attempts.