bluuebunny/crossref_metadata_2025 huggingface dataset:
Projecting the evolution of the urban climate of metropolitan French cities using a convection-permitting model
Authors: Michau Yohanna , Lemonsu Aude , Lucas-Picher Philippe , Caillaud Cécile
Published: February 2023

Urban areas will not be spared from the effect of climate change and will face more and more extreme weather events (e.g., heatwaves and floods). Such changes already cause severe environmental issues, economics damages, and many casualties, especially in cities where most activities and populations are concentrated. Evaluating the impacts of future extreme events on urban areas is a major challenge to prepare the adaptation.Urban areas are very complex systems that require specific modeling tools. The latest advances in regional climate modeling allow simulations to be performed over longer time periods with finer horizontal resolutions of up to few kilometers. The scientific community emphasizes the considerable improvements in using Convection-Permitting Models (CPM), especially for the representation of small-scale phenomena. Also, CPMs offer an interesting modeling framework for studying the interaction between regional climate and urban effects (especially urban heat island) and city-scale impacts through the explicit coupling of the atmospheric climate model with a dedicated urban surface model.In this study, the CNRM-AROME CPM, coupled with the Town Energy Balance (TEB) urban-canopy model, is used at 2.5-km horizontal resolution. Climate simulations were performed on an extended France domain (northwestern Europe) as part of the EUropean Climate Prediction system (EUCP) project over an historical period (1986-2005) and two future periods (mid-term, 2041-2050 and long-term, 2080-2099) using the RCP8.5 emission scenario. Here, scientific objectives are (1) to evaluate the urban heat island evolution for some metropolitan French cities, and (2) to quantify the evolution of specific meteorological hazards on cities and population. With this aim, we selected indicators related to heatwaves (based on Ouzeau et al. (2016) methodology) and heavy precipitation event, considered as some of the most relevant extreme meteorological events. These indicators were tested and evaluated on the evaluation simulation, and then analyzed in a changing climate to quantify the impacts on the cities. The multi-city approach makes it possible to investigate the variability that can exist between cities depending on their geographical and climatic contexts.
Potential of AI classification of the weather radar observations for aeroecological research
Authors: Lukach Maryna
Published: February 2023

The benefits of the application of weather radar observations for aeroecological research are already well known to the scientific community. The advantages of long-term polarimetric weather radar observations for the detection of bird and insect migration or estimation of their abundances are used by different teams all over the world. In this context, a correct, timely, and meaningful interpretation of polarimetric weather radar observations is an important part of these studies. This interpretation requires a well-developed technique that automates the recognition of separate classes in both spatial and temporal dimensions of the data.The study presents a novel data-driven technique for identifying different classes in Quasi-Vertical Profiles (QVPs) and in Columnar Vertical Products (CVP) based on observations made by a dual-polarization Doppler weather radar. The top-down optimal clustering is applied to the detection and identification of aeroecological classes in the QVPs and CVPs. We demonstrate its application to the NCAS X-band dual-polarization Doppler weather radar (NXPol) data and the potential of its application to the C-band data of the Met Office radar network. This technique is generally applicable to similar multivariate data from other observational instruments and will improve quantitative observation and monitoring of biodiversity in the UK.
Main drivers of the seasonal and annual changes in phosphorus content in the Guadaira river (South of Spain)
Authors: Jurado-Ezqueta Manuel Jesús , Contreras Eva , Hidalgo Cristina , Serrano Laura , Polo María José
Published: February 2023

High amounts of nutrients favor the growth of algae that consume oxygen from the aquatic environment causing eutrophication. In the case of phosphorus, it comes mainly from two sources: fertilizers washed from agricultural areas by runoff water and urban and industrial development. In the first case, the phosphorus loads do not have a clear point of entry into the water channels, whereas in the second one, the phosphorus loads can be generated from point sources, such as discharges from the wastewater treatment plants (WWTP) but also from non-point sources, such as urban areas runoff in episodes of intense rainfall. The main purpose of this work is to analyze the content of phosphorus in water for more than 40 years and inquiry into the origin of the sources that may have produced the phosphorus loads. For this purpose, the Guadaira river basin (South of Spain), where agricultural land uses converge with numerous human activities resulting in high pressures on water quality, was selected. The results highlight that the phosphates threshold value established for good/moderate state (0.32 mg PO4/l) is exceeded by 96% of the measurements during the period 1981-2022 in a water quality control point located downstream of the main WWTP, which threat the wastewater of Seville, and that in addition collects the contributions from the other WWTPs and agricultural lands located in the basin. The episodes of sediment contribution that occurred during the period 1981-2022 were analyzed at this control point, and from the 184 episodes found, 30 episodes may have been due to runoff (which also may have originated from agricultural areas or from the overflow of water collectors) (type 1 episodes) and 79 may have been due to urban spills (type 2). 80% of both types of episodes were found to be higher than 1.5 mg/l being able to reach concentration values of up to 14 mg/l. Most of the episodes of dry months were categorized as type 2, reaching the highest concentration values (8-17 mg/l), while type 1 episodes were mostly present in rainy months.Finally, despite the increase of the stable population (+0.52% ∼ +1.42% per year between 2000 and 2012) and tourism (average ≈ +3.23% per year), the WWTP improvement has achieved a decrease in the mean phosphorus concentrations of -0,2% per year. Despite the investment in the WWTP of the basin is necessary to improve its operation and efficiency as well as its adaptation to the increase in population and tourism to ensure better water quality of the water resources.Acknowledgements: This work has been funded by the project TransDMA – Adaptation of the Water Framework Directive to the Andalusian reality: The Guadalquivir estuary as an integrated management model, promoted by the Ministry of Economy, Knowledge, Business and University and co-financed by the operational program FEDER 2014-2020 in Andalusia.
Digital Outcrop Modeling of The Eocene Rus Formation; Implications to Sedimentology and Structural Geology, Saudi Arabia
Authors: Osman Mutasim
Published: February 2023

The King Fahd University of Petroleum & Minerals (KFUPM) campus features good exposure of the Eocene Rus Formation. This region, which is referred to as the Dammam Dome's apex, is what caused the Rus Formation's primary and secondary deformations. Despite the fact that these structures attracted numerous researchers and produced high-quality documentation and published work, a variety of data covering all the outcrops on the KFUPM campus is still lacking. In this study, 10 outcrops were used, and for each outcrop, high-resolution 3D photographs were captured together with sedimentological and structural data. The outcrops range in height from 5 to 7 meters, in width from 200 to 400 meters, and most of them include at least three distinct sets of fractures. The bed-by-bed sedimentological information includes lithology, grain size, texture, sedimentary structures, and fossils. The structural data also includes the thickness of the beds as well as the strike and dip of a representative number of fractures. To be used in the digital models, the images and all of the obtained data were geo-referenced. A new 3D outcrop model visualization and analysis tool has been created in-house, by the remote sensing team in KFUPM, with a focus on the ability to load and show massive outcrop model datasets in fully georeferenced coordinates (either in colored point cloud or textured TIN-mesh formats). Sedimentological and structural analysis tools have been created to do interactive study & annotation of the outcrop. All of the data from each outcrop were combined to form the results of this study, and the structural measurements were validated with an accuracy of +/- 5 degrees only for the measures of strike and dip. The Rus Formation digital models were also used to teach undergraduate students cutting-edge technologies and to bring the field into their desktops. Future plans and proposals call for integrating digital models with geophysical data such as seismic and GPR to increase value and benefits.
Rewriting the tale of deep-ocean upwelling
Authors: Naveira-Garabato Alberto C.
Published: February 2023

Since the seminal work of Walter Munk in the 1960s ('Abyssal Recipes'), oceanographers have believed that the upwelling of cold, abyssal waters that regulates the deep ocean's ability to sequester heat and carbon for decades to millennia is mainly driven by centimetre-scale turbulent mixing associated with breaking internal waves in the ocean interior. Measurements of deep-ocean turbulence over the last >20 years, however, have contested this scenario, and instead suggest that mixing by breaking internal waves drives *downwelling* of abyssal waters. Inspired by this conundrum, recent theoretical investigations have developed an alternative view of the role of mixing in sustaining deep-ocean upwelling. In this new view, upwelling is driven by highly localised turbulence within thin (typically tens of metres thick) layers near the seafloor, known collectively as the bottom boundary layer. In the BLT Recipes experiment, we recently set out to test this new view, and figure out how it works, by obtaining the first set of concurrent, systematic measurements of (1) large-scale mixing and upwelling, (2) their interior and bottom boundary layer contributions, and (3) the processes underpinning these contributions, in a representative deep-ocean basin (the Rockall Trough, in the Northeast Atlantic). This talk will review the insights emerging from the BLT Recipes experiment, and offer an outlook on how they might re-shape our understanding of the way in which turbulence sustains deep-ocean upwelling.
Fast-track assessment of flash flood - erosion - landslide risks in fire-stricken river basins of the region of Attica, Greece
Authors: Kontoes Charalampos (Haris) , Loupasakis Constantinos , Tsouni Alexia , Tsangaratos Paraskevas , Sigourou Stavroula , Pagana Vasiliki
Published: February 2023

The Region of Attica, the most densely populated region of Greece, which includes the capital, Athens, and contains critical infrastructures and social economic activities, was stricken by large forest fires in 2021 that caused incalculable damage. Thus, it was deemed necessary to conduct urgent assessment of flash flood-erosion-landslide risks in the small-sized fire-stricken river basins, with a view to prioritizing the required urgent interventions. For this purpose, the Operational Unit "BEYOND Centre of EO Research & Satellite Remote Sensing" of the Institute of Astronomy, Astrophysics, Space Applications & Remote Sensing (IAASARS) of the National Observatory of Athens (NOA), in cooperation with the Laboratory of Engineering Geology and Hydrogeology of the National Technical University of Athens (NTUA), studied the five river basins in the region of Attica that were affected the most by the aforementioned forest fires. Both research groups collected and studied all available geospatial data, and conducted extensive field visits in the areas of interest for on-site observation and collection of additional data, emphasizing at residential areas, road network and other critical infrastructures, and run hydrological, hydraulic, soil erosion and landslide models at high spatial resolution. All the collected and produced data, the flood hazard and landslide susceptibility maps, as well as the identified critical points and the proposed mitigation measures (both short-term and long-term) were delivered to the decision makers of the Prefecture of Attica and the 11 affected Municipalities, and access was given to the dedicated online platform which was specially developed for the needs of the authorities. Overall, 224 critical points were identified, 136 for flood and 88 for landslide risks. Presentations were organised for all the relevant stakeholders and the public. Subsequently, mitigation measures were applied to the most critical points by the Prefecture’s technical services. The methodology and the outputs of the project are in line with the requirements for the implementation of the EU Floods Directive 2007/60/EC, the Sendai Framework for Disaster Risk Reduction, the UN SDGs, as well as the GEO’s Societal Benefit Areas.
Venus Dynamics Tracer (VdT) - a mission dedicated for in-situ measurements of the Venus atmosphere.
Authors: Stenberg Wieser Gabriella , Yamauchi Masatoshi , Persson Moa
Published: February 2023

Recent Venus missions (Venus Express and Akatsuki) provided a large-scale view of Venus atmosphere and discovered new phenomena, such as high-altitude extension of the mountain wave to the cloud layer and a dawn-dusk asymmetry in the ionospheric motion.  The superrotation of the cloud layer is assumed to be driven by the thermal tide but its relation to any meridional convection or waves is still unknown.  The key to understand all these phenomena is to determine the multi-step re-distribution of the absorbed solar radiation to other forms of energy: (1) internal energy; including temperature, latent heat, and chemical energy (2) kinetic energy both in large scale flows/waves and in minor deviations of convection motions, (3) electric energy including ionization. To understand how the motion of Venus atmosphere is driven by the energy originating from the absorption of solar radiation, we proposed Venus Dynamics Tracer (VdT), a mission for in-situ measurements, as a response to the ESA call for new M-class missions.  Specific targets were two major energy absorption regions: the cloud layer and the ionized upper atmosphere. The scientific goals were to investigate (a) the roles of the vertical and meridional circulation in maintaining major atmospheric dynamics near the cloud layer where visible light is absorbed and drives the vertical motions of the air, and to understand the (b) global dynamics of ions and neutrals in the upper atmosphere where EUV is absorbed both by neutrals and ions and where energy and momentum are transferred between them.  For the first target, multiple-balloons are deployed for in situ observations with supporting camera/s on an orbiter giving global context. For the second target, the motions of ions and neutrals are directly measured.  This presentation discusses required measurements to answer the scientific goals.  
Microbial communities investigation and biocontrol activity in saffron cultures
Authors: del Gallo Maddalena , Farda Beatrice , Djebaili Rihab , Sabbi Enrico , Ercole Claudia , Pace Loretta , Pellegrini Marika
Published: February 2023

Crocus sativus L., commonly known as saffron, is recognized as one of the most valuable spices in the world for the flavouring, nutritional and bioactive properties of its dried stigmas. As underground organs, saffron corms are exposed to infections caused by fungi, bacteria, viruses and nematodes. Among the latter, the genus Fusarium includes fungal pathogens that destroy these cultures, affecting also the composition of the microbial communities associated with the plant. The corms are typically chemically disinfested before sowing to control diseases. However, most fungal pathogens, such as Fusarium spp., are resistant to this treatment. The aim of this work was to i) investigate the microbial communities associated with the rhizosphere of saffron in presence of fusariosis; ii) isolate and characterize the Fusarium pathogen strains; iii) evaluate the biocontrol potential of selected beneficial bacterial strains against the isolated phytopathogens. Soil and plant samples of the saffron cultures were sampled in L’Aquila territory (Italy) and analysed with microbiological approaches, including culture–independent and – dependent methods. The 16S rRNA metabarcoding ITS barcoding was performed to investigate microbial communities composition and identify fungal pathogen isolated strains respectively. Four beneficial bacteria were tested against phytopathogen strains by dual culture method and microscope observations. The metabarcoding analysis revealed the presence of taxa related to the Proteobacteria phylum. The three isolated fungal strains were identified as Fusarium oxysporum ff. spp. and two of the four selected beneficial strains (Bacillus pumilus and WG6) showed an inhibition percentage greater than 50% with disgregation and vacuolization of the hyphae. These preliminary findings serve as the basis for future studies about the possibility of asses more sustainable agricultural practices and eco-friendly strategies to avoid or mitigate Fusarium disease in saffron cultivation and protect a such valuable and precious plant.Keywords: Fusarium, pathogens, biocontrol
Potential effects of climatic trends on crop yield in the Mediterranean
Authors: Santiago-Ventura Emilio F. , Román-Sánchez Andrea
Published: February 2023

Current climatic conditions tend to increase the frequency of droughts and may lead to increased aridity and evapotranspiration. This trend can cause adverse effects on agricultura due to water stress. Spain is the only country in Europe that is being affected by a characteristic aridity process according to USGS (2017). Andalusia, Southern Spain, is the most important agricultural region in Europe and one of the hardest affected by aridity. However we know little, if anything, about the relationship between aridity and crop yields in this region. Using data from ECAD and AEMET from more than 100 weather stations over the period 1959-2022, the temporal and spatial variability and trend of temperature and precipitation are analysed. Calculations are made for several indices of drought, aridity, continentality and oceanity to examine the relationship between them and the yield of a wide variety of crops. A high concentration and reduction of precipitation has been observed and the results obtained reflect a correlation between these indices of aridity, drought and continentality and the yield of selected crops. The trend of increasing aridity can be considered as a key factor in crop yields, especially in rainfed crops.
Ecohydrology the scientific background for implementation of Nature Based Solutions towards  mitigation hydrological extremes
Authors: Zalewski Maciej
Published: February 2023

Water is a key determinant of ecosystem’s structure as far as is driving carbon, phosphorus and nitrogen cycling, thus determine ecosystem biodiversity, bioproductivity and services for society. The understanding of  interplay between hydrological and ecological processes which is a merit of ecohydrology becomes fundamental for development and implementation of Nature-Based Solutions (NBS) and Hybrid Solutions (integrating NBS with hydroengineering solutions) for water management in the catchments.

In order to reverse the degradation of natural and urban ecosystems, as well as  to mitigate extremes (floods and drought) resulting from progressive Climate Change, the key challenge  is necessity of enhancement of catchment multidimensional sustainability potential WBSR (water, bioproductivity, biodiversity, ecosystem services and resilience). This becomes critical as far as  climate change often leads to xeroseries which reduces bioproductivity and biocomplexity of catchment ,  which in turn causes decline in biodiversity. On the other hand all above effects negatively integrity of all processes of water and nutrient cycles and ecosystem services . 

The implementation of EH NBS for mitigation of hydrometeorological extremes has to be based on a new paradigm and methodology, which expands IWRM and  will be introduced during the conference.
Exploring deep root water uptake, soil moisture, and land surface fluxes in the Amazon
Authors: Bieri Carolina , Dominguez Francina , Miguez-Macho Gonzalo , Fan Ying
Published: February 2023

Plant roots act as critical pathways of moisture from subsurface sources to the atmosphere. Moreover, deep plant roots allow vegetation to meet water demand during seasonally dry periods by taking up moisture from accessible groundwater. This is an important resilience mechanism in the Amazon, a hydrologically and ecologically significant region. However, most regional land-atmosphere computational models do not adequately capture the link between deep roots and groundwater. This study details the implementation of a dynamic rooting scheme in the Noah-Multiparameterization (Noah-MP) land surface model, a widely used tool for studying the exchange of energy and moisture between the land and atmosphere. The rooting scheme is a first-order representation of dynamic rooting depth based on the soil water profile and includes quantification of deep root water uptake (RWU). The scheme is easily scalable and ideal for regional or continental-scale climate simulations. It is used in conjunction with a groundwater scheme which captures high-resolution spatial groundwater variations, allowing us to capture the critical link between deep roots and groundwater. We perform 10-year simulations with and without the root scheme for a test region in the Amazon to validate the enhanced model. We analyze time series of soil moisture, RWU, and evapotranspiration for points with differing vegetation cover and elevation. This allows us to demonstrate functionality of the root scheme and ensure it behaves properly for varying conditions. Representation of deep RWU is critical for realistic simulation of the soil-plant-atmosphere system. As the land surface is an important component of atmospheric predictability, inclusion of deep RWU can contribute to improved prediction of atmospheric variables such as precipitation. 
Data-driven seasonal forecasts of European heat waves
Authors: Materia Stefano , Jung Martin , Donat Markus G. , Gomez-Gonzalez Carlos
Published: February 2023

Seasonal Forecasts are critical tools for early-warning decision support systems, that can help reduce the related risk associated with hot or cold weather and other events that can strongly affect a multitude of socio-economic sectors. Recent advances in both statistical approaches and numerical modeling have improved the skill of Seasonal Forecasts. However, especially in mid-latitudes, they are still affected by large uncertainties that can limit their usefulness. The MSCA-H2020 project ARTIST aims at improving our knowledge of climate predictability at the seasonal time-scale, focusing on the role of unexplored drivers, to finally enhance the performance of current prediction systems. This effort is meant to reduce uncertainties and make forecasts efficiently usable by regional meteorological services and private bodies. This study focuses on seasonal prediction of heat extremes in Europe, and here we present a first attempt to predict heat wave accumulated activity across different target seasons. An empirical seasonal forecast is designed based on Machine Learning techniques. A feature selection approach is used to detect the best subset of predictors among a variety of candidates, and then an assessment of the relative importance of each predictor is done, in different European regions for the four main seasons.Results show that many observed teleconnections are caught by the data-driven approach, while a few features that show to be linked to the heat wave propensity of a season deserve a deeper understanding of the underpinning physical process.
Spatial modelling of seabed sediments in the Dutch North Sea with a Random Forest
Authors: Dabekaussen Willem , Stam Jelte , van Heteren Sytze
Published: February 2023

Maps of seabed-sediment composition are among the most sought-after geological data products in the marine domain. The Dutch part of the North Sea is one of the busiest marine sectors in the world with energy, food supply, sand mining and nature competing for space. To enable information based decisions it is important to have up-to-date maps and models. Seabed-sediment maps currently in use for the Netherlands are hand drawn maps, originating from the 1980s and 1990s. With the amount of developments on the North Sea there is a high demand for reproducible maps containing recent information. This requires a faster and more robust mapping methodology.

The Geological Survey of the Netherlands maintains a database containing subsurface information, including some 14.000 offshore sample locations. The data is quite heterogeneous and as a first step the visual descriptions and/or laboratory grain size analyses are homogenized to relative mud, sand and gravel proportions. The interpolation of the point data was performed using a Random Forest (RF) Machine Learning algorithm. The model was trained to predict sediment properties based on a set of predictor features. A wide range of predictor features has been tested, including spatial coordinates, (derivatives of) bathymetry and available external data like suspended matter and current speed velocities.

Considering that the resultant seabed-sediment map shows sediment classes, two strategies can be followed: i) regression modelling of grain size proportions will result in a RF output as continuous variables, subsequent classification then results in a sediment-class map, or ii) classiffication of sample grain size proportions enables classification modelling, directly resulting in a sediment-class map including an uncertainty estimate of the prediction.

Cross-validation results show that sediment class interpolation outperforms regression interpolation of grain size proportions. Validation of the predicted class probabilities shows that the RF produces accurate probabilities that can be used as a reliable uncertainty estimate. Based on cross-validation results and visual inspection of the classified map the most suitable set of predictor features were identified. RF proved to be well capable of generating a trustworthy seabed-sediment composition map, enabling calculation of maps that are easy to update with information from new sampling campaigns.
Public involvement in the design and implementation of infrastructure projects.
Authors: Dimitrakopoulou Dimitra , Ioannidis Romanos , Dimitriadis Panayiotis , Iliopoulou Theano , Sargentis George-Fivos , Chardavellas Efthymios , Mamassis Nikos , Koutsoyiannis Demetris
Published: February 2023

Infrastructure projects, although associated with public health and well-being, are often faced with opposition movements during their design and implementation. In this work, public involvement is investigated as means for comprehending the reasons behind any public opposition during the implementation of civil infrastructure works. More specifically, three courses of actions are proposed in order to initiate public engagement in the design process of infrastructure projects, i.e., (i) the collaboration with municipalities, institutes and universities for collection of data and previous studies in the area, (ii) the indirect communication with the public through online questionnaires, and (iii) the direct communication with the public during field works and by loose-format interviews regarding their experiences. After statistically evaluating the information acquired by the input data, it is concluded that the combination of the above actions can enhance the engineers’ knowledge at the area of interest, and thus, may result in a more efficient design of civil works, but also, in the public engagement during and after their implementation.
Digital mapping of soil classes with imbalanced class observations: A case study of Lombardy region, Italy
Authors: Adeniyi Odunayo David , Maerker Michael
Published: February 2023

Mapping soil classes to retrieve information for specific soil management strategies according to capabilities and limitations of soil types is an important and very useful application of Digital Soil Mapping (DSM). DSM involves the application of mathematical methods to develop models that explain the spatial distribution of soil characteristics using environmental variables as predictors. Machine learning (ML) algorithms is related to the ability to quantify the high-dimensional and nonlinear relationships between soil characteristics and environmental variables over diverse soil landscapes. However, most common ML algorithms works well on balanced datasets having classes that are approximately represented equally. However, imbalanced soil property class observations might lead to an underestimation or loss of minor classes (small N) and an overestimation of major classes (large N) while modelling with ML algorithms. In this study, we addressed this problem by investigating different resampling strategies such as data resampling techniques and synthetic resampling techniques, which have been developed to counteract imbalanced data problems. We compared the performance of three of the most common ML algorithms (decision tree, random forest, and multinomial logistic regression) with the respective resampling approaches in an agricultural lowland area of Lombardy region, Italy. The study helps to identify: i) the effect of using imbalanced distribution of class observations in digital soil mapping, ii) the resampling strategy that improves and gives better performance, and iii) the best performing predictive model for soil classification for lowland areas combined with an appropriate resampling strategy. The results yield valuable information on how to deal with imbalanced class observations for digital soil mapping in an agricultural lowland area.

 
Characterization of cellulose decomposed by saprotrophic fungi using Raman spectroscopy
Authors: Ahlawat Ashish , Floudas Dimitrios
Published: February 2023

Wood decomposition has been studied extensively due to its importance in wood deterioration and carbon cycling processes. Wood decaying fungi are categorised into white rot, soft rot and brown rot. White rot fungi have an enzymatic mechanism by which they can digest lignin and crystalline cellulose. Instead, brown rot fungi lack the enzymes to digest lignin and crystalline cellulose. Several hypotheses have been made on the mechanism by which brown rot fungi mine carbon out without the required enzymes mainly focussing on extracellular metabolites and metal ions. Here, we investigate chemical and structural modifications on cellulose produced by saprotrophic fungi using Raman specrtroscopy under different conditions. In additions, known modifications introduced by chemicals on cellulose will also be compared to fungal changes on cellulose.
Bridging “Around the world in 80 days” and “Journey to the Center of the Earth”: web-based mapping of exploration seismics data around the globe
Authors: Diviacco Paolo , Busato Alessandro , Burca Mihai , Viola Alberto , Potleca Nikolas
Published: February 2023

Exploration Seismics is one of the most important geophysical methods that could provide insights of the Earth crust up to depths of several Kilometers. This approach has been used widely in many areas of the globe accumulating large datasets that allow to improve the knowledge of the Earth dynamics.Providing access to recent and old datasets to the widest scientific community is of paramount importance to foster, as much as possible, collaborative research among scientists. In this, the possibility to find, preview and possibly process data directly on the web is extremely relevant.National Institute of Oceanography and Applied Geophysics - OGS is deeply committed in developing a web-based framework named Seismic data Network Access Point (SNAP) (https://snap.ogs.trieste.it), that allows scientists to remotely explore data assets that have been acquired by OGS itself and by other research institutions. SNAP is used within several international data dissemination initiatives such as EMODnet, SeaDataNet, SCAR-SDLS and others.These kinds of initiatives often focus on specific areas, such as for example the European Seas or Antarctica, that are located far from each other and that have different needs in terms of projections or bounding boxes. Finding a one-fits-all solution for web mapping and data access to georeferenced data in such diverse environments is not easy.Polar areas, in particular, are as complex to handle as difficult to survey. At the same time these regions are of overwhelming importance for climate studies. The remoteness, extreme weather conditions, and environmental sensitivity of Antarctica make new data acquisition complicated and existing seismic data very valuable. It is, therefore, critical that existing data are Findable, Accessible, Interoperable and Reusable (FAIR). The aim of the SNAP framework and its implementations is to allow seismic data acquired in distant and different regions of the globe to be immediately accessible within a FAIR paradigm, offering all standard OGC compliant metadata models, and OGC compliant data access services.We will present in detail the SNAP web-based framework in the light of Open Data and FAIR principles, and its planned future developments.
Evaluation of the effects of grassland distribution on erosion processes of the loess hillslopes under simulated rainfall
Authors: Sun Ruoxiu , Ma Li , Zhang Jianjun , Hu Yawei
Published: February 2023

Vegetation distribution are of great significance to control soil erosion and water and soil loss on slope.  In order to further explore the influence of slope vegetation distribution on the process of sediment yield and discharge, and quantitatively analyze the relationship between vegetation distribution and sediment yield and discharge. Through field rainfall simulation, under the condition of 15° slope, the sediment yield and runoff were observed under the conditions of different vegetation coverage (40%, 60%), different rainfall intensity (30, 60, 90 mm/h) and different vegetation distribution positions (relative distance 0, 0.2, 0.4, 0.6, 0.8, 1). The results showed that: (1) under a certain slope and rainfall intensity, the runoff yield and sediment yield increased rapidly at first and then tended to be stable under different vegetation distribution conditions. (2) In this study, the average runoff yield and sediment yield firstly decreased and then increased with the increase of the relative distance. The average runoff yield of the slope with the relative distance of 0.2 was the minimum. (3) The random forest algorithm shows that rainfall intensity and vegetation coverage have important effects on runoff yield, and rainfall intensity and vegetation relative distance have important effects on sediment yield. (4) When the vegetation coverage was 40%, the optimal vegetation relative positions were 0~0.36 and 0~0.31, respectively, with the main objective of reducing runoff and sediment. When the vegetation coverage was 60%, the optimal relative vegetation positions were 0~0.43 and 0~0.22, respectively, to reduce runoff and sediment. This study shows that slope vegetation distribution has an important effect on sediment yield and runoff. Under the same vegetation coverage, the smaller the relative distance of the grass belt, the better the effect of reducing runoff and sediment. The research results can provide theoretical basis and data support for optimal allocation of vegetation in the process of ecological restoration.
Drawbacks in modeling debris flow erosion using the shallow water equations and the finite volume method. Examples from FLATModel and the Rebaixader torrent
Authors: Medina Vicente , Hürlimann Marcel , Molano Laura
Published: February 2023

FLATModel (Medina et al. 2008) was developed as a modeling tool for debris flow (DF) events. It includes several specific DF features, among them, a simple erosion mechanism was proposed and implemented. The previous validation of this model capability was based on event volume comparison. Now, a more detailed analysis has been performed, and several constraints in its applicability emerge. Model results for erosion present an important dependence on numerical parameters configuration, hence, not only the physical parameters calibration is required. Accuracy in erosion modeling requires proper numeric setup resulting in high computational effort, compromising the model performance. New specific algorithm or erosion computation approach is required.A part from these numerical aspects, we present some results obtained in the Rebaixader torrent (Central Pyrenees), where a debris-flow monitoring system is installed and annual UAV-surveys are performed.Medina, V., Hürlimann, M., Bateman, A. (2008) FLATModel: 2D finite volume code for debris-flow modelling. Application to different events occurred in the Northeastern part of the Iberian Peninsula. Landslides, 5, 127-142. https://doi.org/10.1007/s10346-007-0102-3
Evolution of Causal Structure of Interactions in Turbulence at the Biosphere-Atmosphere interface
Authors: Kumar Praveen , Rodriguez Leila Hernandez
Published: February 2023

Turbulence at the biosphere-atmosphere interface refers to the presence of chaotic and chaotic-like fluctuations or patterns in the exchange of energy, matter, or information between the biosphere and atmosphere. These fluctuations can occur at various scales. Turbulence at the biosphere-atmosphere interface can affect the transfer of heat, moisture, and gases. In this study, we use causal discovery to explore how high-frequency data (i.e., 10 Hz) of different variables at a flux tower, such as wind speed, air temperature, and water vapor, exhibit interdependencies. We use Directed Acyclic Graphs (DAGs) to identify how these variables influence each other at a high frequency. We tested the hypothesis that there are different types of DAGs present during the daytime at the land-atmosphere interface, and we developed an approach to identify patterns of DAGs that have similar behavior. To do this, we use distance-based classification to characterize the differences between DAGs and a k-means clustering approach to identify the number of clusters. We look at sequences of DAGs from 3-minute periods of high-frequency data to study how the causal relationships between the variables change over time. We compare our results from a clear sky day to a solar eclipse to see how changes in the environment affect the relationships between the variables. We found that during periods of high primary productivity, the causal relationship between water vapor and carbon dioxide shows a strong coupling between photosynthesis and transpiration. At high frequencies, we found that thermodynamics influences the dynamics of water vapor and carbon dioxide. Our framework makes possible the study of how dependence in turbulence is manifested at high frequencies at the land-atmosphere interface.
Mathematical Morphology applied to solar features detection
Authors: Bourgeois Slava , Wagner Andreas , Barata Teresa , Erdélyi Robertus , Oliveira Orlando
Published: February 2023

Mathematical Morphology (MM) is an effective method to identify different types of features visible on the solar surface such as sunspots, facular regions, and pre-eruptive configurations of Coronal Mass Ejections (CMEs), which are important indicators of the Sun’s activity cycle.  On the one hand, we determine sunspots areas in Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA) intensity images with this MM method, and we compare the obtained values with existing solar databases (e.g., the Debrecen Heliophysical Observatory catalogue or Mandal et al.'s catalogue [2020, A&A doi:10.1051/0004-6361/202037547]). The good agreement between the MM results and the existing catalogues validates the method, which we then apply to contour the different magnetic polarities in the SDO/Helioseismic and Magnetic Imager (HMI) magnetograms in order to identify so-called delta-sunspots. The next step is to investigate the correlation between solar flares and the length of these delta-sunspots contours. On the other hand, as another application, MM also helps us to extract flux rope structures from magnetic field models, using twist number maps obtained from a time-dependent magnetofrictional code. We can then investigate the evolution of the magnetic flux rope properties and the underlying triggers for the instability that ultimately leads to an eruption.
Examining the contribution of human induced climate change on global drought characteristics
Authors: Koutroulis Aristeidis , Grillakis Manolis , Seiradakis Konstantinos
Published: February 2023

Drought is generally considered a slow process natural hazard. However, the faster onset and strength of recent events have received great attention. Climate change and human activities can both play a role in altering the characteristics of droughts, including their speed of development and intensity. Climate change can, for example, indirectly impact droughts by changing the amount and distribution of precipitation, while human activities, such as land management, can directly alter the water content of the soil. In this study, we run the JULES-W2 land surface model with the counterfactual stationary ISIMIP3a climate dataset, a hypothetical climate without climate change [1], and transient land use changes based on observations. We use soil moisture as a water deficit indicator and a framework for calculating the hydrological drought propagation speed [2] to define drought characteristics. We compare results against those calculated from historical runs with climate-related forcing based on observations (factual) to examine historical imposed long-term changes attributed to human-induced climate change. Our results show that climate change could significantly impact the speed of development and intensity of droughts. Some regions like Congo rainforest, Europe and the western US are simulated as hot spots of more fierce droughts, while others (e.g. East African mountains) may have faced milder droughts as a result of climate change. These changes can have important consequences for the productivity of agricultural lands, the health of ecosystems, and the availability of water for human use. Future climate change highlights the implications of faster droughts on risk management and challenges the research of drought hazard prediction.  [1] Mengel, M., et al. “ATTRICI v1.1 – counterfactual climate for impact attribution.” Geosci. Model Dev., 14, 5269–5284.[2] WU, Jiefeng, et al. Hydrological drought instantaneous propagation speed based on the variable motion relationship of speed‐time process. Water Resources Research, 2018, 54.11: 9549-9565. Acknowledgements: “Co-funded by the ERASMUS+ Programme of the European Union” (Contract number: 101004049 — EURECA-PRO — EAC-A02-2019 / EAC-A02-2019-1).
Analytic solution of the wave equation in complex structures with defects, waveguides, sources
Authors: Kutsenko Anton
Published: February 2023

We discuss a derivation of the analytic solution of the wave equations in complex structures perturbed by local defects, long waveguides, and various sources. After obtaining the exact analytic form of the solution, the numerical implementation becomes more or less straightforward. The corresponding real-time simulations will be demonstrated. Another important point is that the analytic solutions do not have disadvantages associated with the noise of reflections from the artificial boundaries of the model and other drawbacks inherent in purely numerical simulations. The solution is based on integral and algebraic transforms, including the active use of special functions. Even for linear waves that propagate in inhomogeneous structures, the solution is very complex. This fact probably makes the process of obtaining exact analytic solutions for nonlinear waves practically hopeless.
Short- to seasonal-range streamflow forecasting in reservoirs of the Brazilian National Interconnect Electric Power System
Authors: Freitas Camila , Silveira Reinaldo , Petry Ingrid , Paranhos Cassia , Fan Fernando , Collishonn Walter , Tucci Carlos
Published: February 2023

The Electric Energy Company of Parana (COPEL GeT), the Meteorological System of Parana (SIMEPAR) and RHAMA Consulting company are undertaking the research project PD-6491-0503/2018 for the development of a hydrometeorological seasonal forecasting for Brazilian reservoirs. The project, sponsored by the National Agency for Electric Energy (ANEEL) under its research and development programme, aims the forecasting of streamflow, at temporal scales ranging from 1 to 270 days which are integrated by the National Power System Operator (ONS) through its Interconnected System (SIN). The SIN is composed of more than 150 hydropower plants and reservoirs located over a wide range of climate and hydrological conditions. It is responsible for more than 50% of the total electricity produced in the country. In this work we describe the overall characteristics of this project, comprising its structure, main research results and its usefulness for assisting decision makers in the field of energy, as will be demonstrated through some application sceneries. We used the precipitation short-medium-range, sub-seasonal, and seasonal ECMWF forecasts as input to a continental-scale, hydrologic hydrodynamic model (MGB-SA) to produce streamflow forecasts for the SIN hydropower reservoirs. On the short-medium-range horizon we used persistency and the control member as benchmarks, while in the sub-seasonal and seasonal we used the ESP. On the short-medium-range and sub-seasonal, the ensemble average performance was superior to the control deterministic predictions for ECMWF (MGB-SA), both for the prediction quality metrics and for the event discrimination metrics. On the seasonal forecast, the ECMWF results were consistently superior to the benchmark on the first lead time month, decreasing performance with the horizon. The results of the project are expected to benefit energy generation planning, routine and emergency hydraulic operation (e.g., flood and droughts), as well as energy commercialization procedures in the country.