bluuebunny/crossref_metadata_2025 huggingface dataset:
Monitoring Tectonic Movements with Low Cost GNSS Measurement Systems
Authors: Akpinar Burak , Özarpacı Seda , Aydın Cüneyt , Aykut Nedim Onur , Özdemir Alpay , Oku Topal Güldane , Güneş Özge , Karabulut Fahri , Doğan Uğur
Published: March 2024

Geodetic GNSS (Global Navigation Satellite Systems) measurement systems play a crucial role in studies aimed at monitoring crustal movements. From the past to the present, GNSS measurement systems have served as active measurement tools within the scope of these studies. In these studies, geodetic GNSS measurement systems can be used as continuous reference stations and are primarily employed in campaign-type measurements. However, the setup and operation of continuous reference stations require a significantly high financial budget. On the other hand, campaign-type measurements necessitate simultaneous data collection using multiple GNSS measurement systems, depending on criteria such as the size of the field and the number of points. This, in turn, increases the overall measurement costs. Today, due to the high expenses associated with geodetic GNSS measurement systems, research is being conducted on the use of low-cost GNSS systems in structural health monitoring, displacement determination, and other applications. Since the studies conducted so far have generally been limited to short-term observations at short baselines, there remain questions about the performance of low-cost GNSS measurement systems in monitoring crustal movements. In this study, the objective is to determine the performance of GNSS measurement systems, whose unit costs are considerably lower compared to geodetic GNSS systems, in monitoring crustal movements. For this purpose, two low-cost GNSS measurement systems will be deployed on the northeastern edge of the surface rupture caused by the earthquakes of Mw7.8 and Mw7.6 that occurred in Kahramanmaraş on 06.02.2023. This will enable the continuous monitoring of the post-earthquake effects in the Çelikhan segment on the East Anatolian Fault (DAF). Furthermore, the performance of low-cost GNSS measurement systems will be assessed. In addition to the measurements taken at permanent stations, campaign-type GNSS measurements will be conducted at four different points using both geodetic and two low-cost GNSS measurement systems throughout the project. By processing the data obtained from geodetic GNSS measurement systems and the data acquired from low-cost GNSS measurement systems in the same region, the results will be analyzed. This analysis aims to determine the performance of low-cost systems in monitoring tectonic structures through continuous measurements and campaign-type measurements. This is work is supported by TUBITAK project number 123Y147.
A critical review of petrological data in the Penninic domain of the Central Alps (Lepontine dome and its E-NE metasedimentary covers) 
Authors: Tagliaferri Alessia , Pigazzi Enrico , Morandi Sabrina , Tartarotti Paola , Schenker Filippo Luca
Published: March 2024

In the Central Alps, the Penninic domain is formed by Europe-derived crystalline basement units that experienced a complex geodynamic history. This geodynamic history spans from subduction-related HP-LT (high pressure-low temperature) at ca. 38 Ma up to Barrovian metamorphic conditions peaked at ca. 31 Ma, followed by a more or less pervasive greenschist facies re-equilibration more evident in the northern units. This history led to the piling of polymetamorphic crystalline basement nappes that nowadays are up arched forming the Lepontine dome.The Lepontine dome is a structural and metamorphic dome characterized by a widespread Barrovian metamorphic imprint. The temperatures of the Barrovian metamorphism increment towards the south and have a concentric distribution, locally intersecting the nappe contacts.Here, we present a critical review of petrological data from the literature within the Lepontine dome, coupled with new temperature data computed with Raman spectroscopy acquired on the E-NE margin (up to the Tambo nappe) of the Lepontine dome. This work aims to identify the finite shape of isotherms at the base and on the roof of the Adula HP nappe and to trace the peak temperature conditions according to their relation to the Adula nappe emplacement (pre-, syn- or post- deformation). Two endmembers are envisaged in the literature: (1) a history where the temperature peak is attained during deformation and, according to thermodynamic studies, evolves from a single prograde PT loop, and (2) a post-deformation thermal peak formed after the HP deformation. The spatial distribution of rocks recording these different thermo-mechanical histories and the geochronological ages of the peak thermal conditions will help to postulate coherent geodynamic scenarios.Petrological data from the Lepontine crystalline basement nappes point to peak conditions developed during nappe emplacement. On the other hand, the metamorphism and deformation of the northern metasedimentary covers suggest that a second thermal imprint is responsible for the peak temperatures registered close to the Adula nappe. This might suggest that the heat surplus developed during deformation of the Adula nappe was diffused to the close units also after its emplacement.
Changing discharge patterns of springs characterized by nival flow regimes in the Austrian Alps
Authors: Vremec Matevž , Seelig Magdalena , Seelig Simon , Collenteur Raoul , Wagner Thomas , Eybl Jutta , Winkler Gerfried
Published: March 2024

Alpine spring runoff patterns recorded at gauging stations offer a unique observational window into the hydrological state of Alpine water systems. These systems play a crucial role in supplying water to downstream areas and are particularly sensitive to changes in temperature and precipitation. Using a dataset of spring discharge monitored at 29 stations by the Austrian Hydrographic Service, spanning 24 years, we conducted a trend analysis on both the quantity and timing of mean and extreme flows. The springs, which were clustered into groups based on the Pardé coefficient and autocorrelation analysis, are distributed over the whole area of the Austrian Alps with mean catchment elevation reaching up to 2500 m above sea level. The trend analysis was performed using the Mann-Kendall test and the Theil-Sen slope on seasonally and annually computed statistics describing the quantity and timing of the occurrence of mean and extreme flows. The results indicate that at springs with a nival flow regime (i.e., flow dominated by snow melt), winter discharge increased. However, during the summer period, differences emerged between two characteristic spring groups: (i) springs at higher-elevation catchments, mainly distributed in the west of the Austrian Alps, with a positive trend in summer, and (ii) springs in the eastern part of the Northern Alps, that displayed a decrease in summer discharge. Notably, differences in the trends for timing of maximum and minimum flows were also evident between these two groups. Furthermore, we compared the hydrological trends to precipitation trends in the spring areas to assess relationships between meteorological and hydrological patterns. These findings provide valuable insights into how the spring runoff patterns have evolved in the Austrian Alps over the past 24 years.
Proactive management of dissolved organic carbon (DOC) in drinking water catchments 
Authors: Amezaga-Kutija Ana Lucia , Werner David , Jarvis Adam , Waugh Stewart
Published: March 2024

High levels of organic matter in drinking water catchments are a hazard as there is a known correlation between the presence of organic matter and the formation of trihalomethanes (THMs) during the chlorination stage of water treatment. Organic matter is quantified through the measurement of dissolved organic carbon (DOC) in water.  THMs are potential harmful for human consumption and regulated in drinking water standard, therefore additional chemical loads are required in water treatment to removed THMs which is costly for water companies. Temperature is also known to have a correlation with the formation of THMs during chlorination and the presence of DOC in catchments, meaning this hazard may increase in the future with the predicted changing climate.This study investigates the potential to proactively manage DOC within a drinking water catchment before drinking water treatment to reduce the risk of THM formation during chlorination. The study focuses on a specific catchment in Northumberland, UK, which includes a reservoir that feeds directly into a drinking water treatment plant. A yearlong monitoring scheme is currently being carried out to discover the dynamics of DOC fluxes throughout the catchment and establishing the pathways and sources of DOC loads. Results so far show that for the main tributary to the reservoir DOC loads vary from 65.01Kg/day in normal conditions to 14402.24kg/day in high rainfall, storm conditions. The data collected is being used to determine relationships between DOC load, land use, land management and climate. These relationships will later be utilized in a model which will be used to simulate various scenarios including some future climate analysis. The final aim of the study is to produce a catchment management plan and business plan considering potential DOC load management methods, stakeholder involvement and scenario analysis.
Taiwan Non-Ergodic Ground Motion Prediction Equations for Spectral Accelerations and Instantaneous Powers
Authors: Chao Shu-Hsien , Huang Jyun-Yan , Hsu Chiao-Chu , Lin Che-Min , Sung Chih-Hsuan , Kuo Chun-Hsiang
Published: March 2024

Currently, available Taiwan ground motion prediction equations were developed based on ergodic assumption, which means that the same ground motion prediction equation is applicable to any ground motion scenarios occurred in Taiwan no matter what locations of earthquake sources are; what paths from sources to sites are, and what locations of sites are. However, several recent studies have shown that the regional differences of source, path and site effects of ground motion in Taiwan are significant. As a result, the prediction for some specific ground motion scenarios in Taiwan may be biased, and the aleatory uncertainty of the ground motion may be over-estimated by using current available Taiwan ground motion prediction equations. Based on it, the aim of this study is to develop new Taiwan ground motion prediction equations for spectral accelerations and instantaneous powers based on non-ergodic assumption which are depended on the source and site locations to consider the regional differences of source, path and site effects of ground motion in Taiwan by using available ground motion records, 3-D velocity models, and horizontal-to-vertical Fourier spectra ratios. A better ground motion prediction result with higher accuracy and lower uncertainty will be achieved based on the proposed non-ergodic Taiwan ground motion prediction equations in this study. Structural damage induced by a scenario-based earthquake can be estimated more precisely by using the proposed non-ergodic ground motion prediction models for spectral acceleration and instantaneous power at fundamental period simultaneously.
A unified Bayesian model selection workflow for geophysical free-surface flow
Authors: Kumar V Mithlesh , Kowalski Julia
Published: March 2024

The broad family of shallow flow models arises from depth-averaging the underlying governing balance laws. Depth-averaging yields an analytical model complexity reduction, increasing computational efficiency and reducing the number of model parameters. Consequently, shallow flow models become a desirable choice for various scientific and engineering applications, such as landslide prediction and coastal engineering. In the realm of landslide modelling, different variants of shallow flow models are often tailored - sometimes in an ad hoc manner - to specific physical phenomena, such as basal shear, non-hydrostatic effects, kinetics, or phase change processes. Therefore, selecting the most appropriate shallow flow model for a particular scenario based on quantitative reasoning poses a formidable challenge. Quantifying the uncertainty associated with this model selection is essential to assess the reliability of the predictions of these shallow flow models.Here, we present a unified Bayesian model selection workflow leveraging Gaussian Process emulation — a machine learning technique used for non-intrusive physics-based machine learning. It starts with model calibration, where we generate posterior samples. These are then used to calculate the marginal likelihood, the basis for our model selection. This process faces two computational bottlenecks: significant computational costs involved in numerous model evaluations during calibration and high-dimensional, intractable integrals in the computation of Marginal Likelihood. To address the former, we integrated Gaussian process emulators into the workflow using PSimPy, our in-house Python package, for predictive and probabilistic simulations. For the latter bottleneck, we conducted a comprehensive literature review, with particular emphasis on marginal likelihood computation techniques based on Importance Sampling and implemented single proposal density schemes and integrated them into the workflow.We demonstrate our approach using elementary landslide runout models across varying fidelity levels, investigating the impact of data representation—specifically, comparing point data to time series data—while considering data characteristics such as velocity and distance. Additionally, we calibrated the discrepancy parameter for robust handling of uncertainties associated with the data. Our future work will focus on implementing advanced importance sampling schemes to enhance the computation of the Marginal Likelihood, especially in high-dimensional scenarios. Furthermore, emphasis will be placed on adopting a hierarchical approach to address data uncertainty in conjunction with model inadequacy, which is not accounted for in the existing workflow.
Solar Radiation Forecasts from Large Eddy Simulations and Observations using Ensemble Kalman Filtering
Authors: van Soest Marleen , Jonker Harm , de Roode Stephan
Published: March 2024

The increase in renewable energy production demands forecasting of wind and solar radiation due to their greater variability compared to non-renewable energy sources. The variability in solar energy is primarily caused by clouds. Large Eddy Simulation (LES) proves effective for high-resolution solar radiation prediction, capturing clouds like stratocumulus where large-scale models cannot. LES uncertainty in clouds primarily stems from initial conditions taken from these large-scale models. In this study, an ensemble Kalman filter assimilates observations into LES initial conditions. A large ensemble is created from a limited amount of LES runs by taking advantage of their internal variability. From this ensemble and measurements from the Cabauw measurement site, improved initial conditions are calculated for a range of stratocumulus cases. These cases are simulated without further interference. The method shows a 60% reduction in Root Mean Square Error (RMSE) for shortwave down solar radiation at the initial condition over the unfiltered initial condition. This improvement persists at 45% after 3 hours of simulation, showing the lasting impact of assimilated observational data on predictive accuracy. The decrease can be accounted to a combination of microphysical processes, energy fluxes from the lower boundary condition and the advective tendencies in the model. In future work, possible improvements to these processes will be identified and the method will be evaluated for other sites and cloud conditions.
Modelling phenology in European beech forests as waves of photo-thermal responses
Authors: Bajocco Sofia , Bregaglio Simone
Published: March 2024

Plant phenology, which refers to the timing of cyclic or recurring eco-physiological events in plants, provides key information about the seasonal dynamics of vegetation and ecosystem processes. While traditional phenological surveys imply the visual detection of easily observable events like flowering, bud break and defoliation, phenological patterns may be unclear due to combined effects or compensatory processes of driving variables (e.g., temperature and photoperiod). Monitoring the continuous plant development during a season is essential for interpreting temporal changes between observed phenological phases and the environmental impacts on the plants' seasonal dynamic. This is especially true for deciduous broadleaf forests, like European beech, where the canopy is sensitive to intra-annual climatic changes and extreme events like spring frosts. In this view, remotely sensed vegetation indices (VIs) observations, thanks to their high temporal resolution, provide a reference data source for investigating phenological moments (phenometrics) and trends. However, there are still two major drawbacks to be solved: (i) phenometrics are merely mathematical moments of the VI annual curve and do not represent any ecophysiological phase, (ii) the VI annual profile allows to detect the canopy growth processes of a plant community but does not reveal the dormancy-related processes occurring when the dominant vegetation cover is senescing. To fill this research gap, this work proposes a process-based model, named swell (simulated waves of energy light and life), able to simulate the complete VI intra-annual profile of beech forests based on their photo-thermal responses during the dormancy and the growing season. To this aim, the EU-forest dataset was used as spatial information of the European beech forests (data from 16 ecoregions), the MODIS NDVI (2010-2023) as reference data for swell calibration (4426 pixels) and independent evaluation (6672 pixels), and the E-OBS Copernicus dataset as weather input source. The rationale of swell is that each phenophase starts upon the completion of the previous one and progresses as a function of phenophase-specific photothermal requirements, using temperature and daylength as climatic cues. The swell simulations agreed with MODIS NDVI profiles (RMSE < 0.10, PBIAS < 5%, Pearson r > 0.8) across time and ecoregions, obtaining similar performances in calibration and evaluation and comparable performances with a fine-fitting statistical method fitted yearly (i.e., Elmore). Aggregating NDVI simulations by latitude and elevation bands allowed exploring patterns of beech phenology across Europe, whose dynamics can be inspected to reveal the vegetation response of this species in response to largely variable photothermal conditions.
Suitability assessment of the location for the Natural Based Solution application on drainage systems
Authors: Vranešević Milica , Knežević Milica , Zemunac Radoš , Meseldžija Maja
Published: March 2024

The introduction of Natural Based Solution (NBS) into sustainable agricultural practices is a key issue on which the balancing of intensive agricultural activities with environmental protection depends. In lowland areas with intensive agricultural production, occurrences of extreme amounts of excess water, caused by climate change, increase the need for efficient drainage systems. Within the comprehensive framework of drainage system improvement, NBS are emerging as key and versatile interventions. The principal challenge lies in reconciling these solutions with the prevalent technical paradigms in both land reclamation and agriculture. The most important change is the strategic integration of the use of riparian buffers as supplementary melioration measures in delineated areas, especially aimed at reducing the inflow of excess water into the canal network. Deciding where to implement NBS for better drainage systems comes down to assessing the risks that may occur as a consequence to natural resources such as water and soil. When the implementation of NBS determines the crucial factors and evaluates them effectively, then it can categorize and map the optimal places where improvement of the drainage system is possible and efficient. In this study the aim was to delineate suitable zones for implementing nature-based solutions along watercourses through the application of Geographic Information System (GIS) methodology. By overlaying different layers, including pedological and geomorphological maps, digital terrain models indicating land slope, land use classifications, and drainage classes, it is intended to analyze and identify optimal locations. Some of the characteristic drainage systems in Vojvodina have been selected to provide a relevant case study illustrating how GIS can be applied to demonstrate the potential of nature-based solutions in improving drainage systems. This approach not only enhances the efficiency of the existing drainage systems. It also provides insights for strategic afforestation and the increase of biodiversity in agricultural areas.
Temperature evolution across the 8.2 ka event based on speleothem fluid inclusion water isotopes from Milandre Cave (Switzerland)
Authors: Affolter Stéphane , Cheng Hai , Fleitmann Dominik
Published: March 2024

Hydrogen (δD) and oxygen (δ18O) stable isotopes contained in speleothem (cave carbonate) fluid inclusion water allow the quantitative reconstruction of past temperatures. Reconstructions can be based either on the use of a regional modern transfer function between isotopes in precipitation and temperatures (expressed in ‰ / °C) or based on the fractionation between the oxygen isotopes measured in the calcium carbonate and in the corresponding inclusion water. One advantage of this proxy is that temperature reconstruction is constrained by chemico-physical processes. Based on a δD gradient of 3.84‰ / 1°C, we reconstructed quantitative temperature variations occurring during the interval 9.0 ka to 7.8 ka BP for the central and western Europe area with a mean temporal resolution of approximately 25 years. The isotope profile shows that the 8.2 ka cold event is characterized by negative shifts in δD and δ18O consistent with numerous records from across the Northern Hemisphere such as for example Mondsee and Ammersee lake sediments in central Europe or at a larger scale in ice cores from Greenland. Across the 8.2 ka event, the new high-resolution Milandre Cave Fluid Inclusion Temperature (MC-FIT) shows a remarkable similarity with the physically constrained temperature reconstruction from Greenland ice cores that is based on nitrogen and argon isotopes of trapped air (Kobashi et al., 2017). This record, supported by additional speleothems from a neighboring cave, provides a better understanding of the continental temperature evolution across the 8.2 ka event.Affolter S. et al.: Central Europe temperature constrained by speleothem fluid inclusion water isotopes over the past 14,000 years. Sci. Adv.5, eaav3809. DOI:10.1126/sciadv.aav3809, 2019Kobashi, T., Menviel, L., Jeltsch-Thömmes, A. et al.: Volcanic influence on centennial to millennial Holocene Greenland temperature change. Sci Rep 7, 1441. https://doi.org/10.1038/s41598-017-01451-7, 2017
Mapping open burning of agricultural residues from Earth Observations
Authors: Oliveira Eduardo , Gata João , Lopes Diogo , Disperati Leonardo , Gama Carla , Silva Bárbara
Published: March 2024

Agricultural residue burning is a common practice in various regions of the world, which may have several environmental impacts, including on air quality, and the potential for triggering wildfires. In Portugal, this practice is particularly prevalent during the wet season, spanning from October to April. It involves open field burning of pruning residues and extensive burning to clear shrubbery, creating pastures for livestock. This research, conducted within the framework of the PRUNING project - Mapping open burning of agricultural residues from Earth Observations and modelling of air quality impacts- aims to explore the potential for detecting such events through satellite remote sensing.
The primary focus of this study is to assess the limitations of satellite remote sensing detection, with the overarching aim of integrating these findings into a systematic monitoring framework for open burning of agricultural residues. Additionally, the study aims to predict pollutant emissions and assess their impacts on air quality, providing valuable insights for environmental management and sustainable agricultural practices.
To achieve this goal, an in-depth analysis of known burning events was conducted using infrared thermal sensors. Multiple products, including Fire Radiative Power and fire masks from various sensors (e.g., MODIS, VIIRS, and Sentinel 3), were employed to characterize these known open field burning events. The results of this work allow verifying the tradeoffs effects associated with spatial, spectral, and temporal resolutions for each sensor, elucidating their impacts on the precision and accuracy of event detections. In parallel, this study evaluated the accuracy of the MINDED-FBA method in characterizing these known events. This automatic detection method, allows incorporating data from higher spatial resolution sensors (e.g., Sentinel-1, Sentinel-2, Landsat), for determining the extent of burned areas through multiple multispectral indices. In this context, the MINDED-FBA method may also be used to validate thermal anomalies detection products. Finally, the results of this work have also been compared to a national level register database of open burning, provided by the ICNF (Institute for Nature Conservation and Forests).
Assessment of Coastal Concrete Structures Exposed to Extreme Weather Conditions using Concrete Petrography (ASTM C856)
Authors: Ybañez Audrei Anne , Aguda Nancy , Cuyno Kate , Jimenez Jeremy James , Tanpoco Chelly Mei , Antonio Reyno , Arcilla Carlo
Published: March 2024

Concrete is used worldwide; however, it is susceptible to fluctuations in temperature and exposure to moisture. Coastal concrete structures, in particular, are exposed to extreme conditions brought about by hydrometeorological processes. The Philippines, as a maritime country, is highly dependent on its coastal structures for its economic development, mobility, and national defense. The country is exposed to the impacts of extreme conditions and natural hazards by virtue of its geologic setting.In this study, concrete assessment is applied to three major ports using concrete petrography complemented by standard physical tests. Petrography offers information on concrete composition, distribution of air voids, water-cement ratio used, depth of carbonation, and the presence and degree of cracking and concrete deterioration phases. The use of petrography in concert with physical testing greatly expands the understanding of the impacts of extreme coastal conditions to these port structures. Structures assessed exhibited carbonation of the cement paste and the presence of cracking, alkali-silica reaction, and delayed ettringite formation. The researchers investigated further, the possible causes of the concrete degradation including the material sources, the existing coastal and climatological conditions on site, and past extreme weather events such as tropical storms and high waves. These technical findings will contribute to the formulation of standards and recommendations on appropriate concrete cover thickness and mix designs for the assurance of resilient coastal concrete structures in the face of extreme weather conditions.
Modelling the Circulation of Hot exoplanet Atmospheres (MOCHA): exhaustive comparison of 3D models for hot Jupiters
Authors: Iro Nicolas , Fauchez Thomas , Komacek Thaddeus , Rauscher Emily , Teinturier Lucas
Published: March 2024

With the first exoplanet JWST and Cheops data available, and ARIEL in the near future, we are expecting to get a lot of time-varying measurements of exoplanets (e.g. phase curves and 3D eclipse maps), giving us unprecedented information about their climate. Hot Jupiters will be the best targets for  atmosphere characterisation with these facilities. 3D atmospheric circulation models are the main tools to interpret theoretically these upcoming observations, however, it is overwhelming to compare the numerous models developed independently with each various assumptions and setup. Some characteristics of their outputs are then dependent on the model used, impairing physical interpretation. It is therefore necessary to assess the differences, limits and applicability of each models in a controlled manner. We present MOCHA (Modelling the Circulation of Hot exoplanet Atmospheres), the most extensive intercomparision of hot Jupiter 3D circulation models. Our team is built from the experts developing all available codes,  in order to set up a common benchmark methodology.Our intercomparison project will provide the exoplanet community with protocols and methods to benchmark current and future 3D models. This will lead to better and more robust tools to retrieve physical information from JWST, Cheops, and later ARIEL data. This project is part of CUISINES (Climates Using Interactive Suites of Intercomparisons Nested for Exoplanet Studies), which has already provided Model Intercomparisons Projects (MIPS) such as THAI for the TRAPPIST planets and CAMEMBERT for mini Neptunes.
Large wood recruitment and transport during a severe flash flood in Central Spain, September 2023.
Authors: Lucía Ana , Sandoval-Rincón K. Patricia , Vázquez-Tarrío Daniel , Garrote Julio , Hernández-Ruiz Mario , Perucha María Ángeles , Romero Amalia , Díez-Herrero Andrés
Published: March 2024

In the face of escalating climate change and an expected increase in extreme precipitation events leading to extreme floods, this work addresses the understudied but critical aspect of woody material in river systems. We aim to understand the dynamics of large woody debris during a severe flood and the evolution of floodplain vegetation in the periods between floods.The study area is the River Alberche and its tributary, the River Perales (Tagus Basin, Central Iberian Peninsula). These were affected by an exceptional cut-off low weather situation (DANA in Spanish) in September 2023 producing heavy precipitation (up to 200 l/m2) and flash floods. This event flooded urban areas, damaged or destroyed four bridges, and resulting in two deaths. One of the damaged bridges had retained a significant deposit of large and fine woody material. After the flood, as usual, critical voices emerged from the affected population calling for the removal of woody material from the riverbeds. However, there are positive contributions of wood in rivers, enhancing hydro-morphological diversity and serving as a source of organic matter. Nevertheless, uncertainties remain regarding the dynamics and amounts of woody material, which warrant a comprehensive investigation.This research aims to fill existing gaps by investigating the dynamics of woody material transport under these exceptional flow conditions through a post-event forensic survey. In addition, it aims to understand river bed vegetation during non-extreme flood periods. The knowledge generated will contribute to the development of basin-scale models that integrate woody material, thereby improving the accuracy of flood risk assessments and enabling the formulation of effective mitigation strategies.
Impacts of Climate Change on Small Island Nations: A Data Science Framework using Remote Sensing and Observational Time Series
Authors: Prasow-Émond Myriam , Plancherel Yves , Mason Philippa J. , Piggott Matthew D. , Wahl Jonas
Published: March 2024

Small Island Developing States (SIDS) comprise a group of 58 nations identified by the United Nations as facing unique sustainability challenges. These challenges include high exposure to climate change and a lack of data and limited resources. The effects of climate change are already observed in SIDS, notably an increase in the magnitude and frequency of natural disasters, biodiversity loss, ocean acidification, coral bleaching, sea-level rise, and coastal erosion. The coastal zone is considered to be the main economic, environmental, and cultural resource of SIDS, making them particularly vulnerable to the adverse effects of climate change. This project focuses on quantifying and disentangling coastal changes, including erosion, accretion and coastline stability. Existing literature lacks a comprehensive understanding of the patterns of coastal changes, as well as the main anthropogenic and environmental drivers involved. We address this research gap by quantifying the challenges that SIDS encounter, with a particular emphasis on coastal changes.The approach is data-driven, relying on observational time series extracted from remote sensing (e.g., Sentinel-2, Planet Scope, Landsat missions), in situ measurements (e.g., tide gauge data), and open-access databases. We have developed a robust method based on image segmentation to extract the island's shape over time, enabling us to illustrate the island's dynamics and obtain reliable time series of the coastline position. The main drivers of coastal changes are then identified and quantified using time series analysis methods, including causal inference and discovery methods, for SIDS worldwide. We place a specific focus on the Maldives (Indian Ocean) due to its low elevation and high human activity. Additionally, the methodology expands to investigate a spectrum of issues, including the impacts of human activities (e.g., land reclamation, sand mining, shoreline armouring) on the natural responses of coastlines, as well as the effects of confounding factors or common drivers (e.g., Indian monsoon, tropical cyclones, and El Niño/Southern Oscillation). The ultimate goal is to develop a spatiotemporal variable coastline vulnerability index by integrating socioeconomic and environmental time series data, facilitating the assessment of environmental policies in SIDS.
Leaching of Soil Microplastics Through Meso- and Macrofuanal Community Transport (manuscript introduction)
Authors: Quigley Elise , Briones Maria JI
Published: March 2024

Transport of microplastics (MPs) in terrestrial compartments has been a growing body of research in recent years, however many of these soil models do not include the realistic role that soil organisms play in terrestrial MP movement. Here, we explore, for the first time, MP transport capabilities of multiple soil species from various ecological niches to investigate complex community structure’s interaction with MPs. Soil column mesocosms were incubated for 18 weeks with 250mg LLDPE (300-600µm) placed on soil surface and introduced were communities of naturally sourced earthworms from single and combined ecological niches (anecic, epigeic and endogeic) along with further integration of the three major ecological niches of collembola (epedaphic, hemiedaphic and euedaphic). Infiltration was performed bi-weekly to simulate intermittent rainfall events and to investigate leaching potential of microplastics through the soil columns with and without the influence of organisms. Throughout the experiment MPs were counted from leachate collected every two weeks and at the end the columns were separated into 11 layers to analyze the distribution of MPs. The presence of anecic, deep burrowing, earthworms significantly increased transport of MPs through the column into the leachate, yet there was an additive effect of leached MPs with all three types of earthworms present together and an even more so when collembola were present with anecic and all earthworms together. Thus, complex community structure increases vertical transport of MPs. At the end of the experiment significantly more MPs were still present at the soil surface of treatments with no organisms and only collembola present, treatments with earthworms present had much less MPs at soil surface and more integration of MPs in each soil layer throughout the entirety of the column. This study highlights the importance of factoring in realistic communities of soil inhabitants as a driver for intensified MP movement and needs to be considered in MP transport modeling.
Forecasting tropical high-impact rainfall events using a hybrid statistical dynamical technique based on equatorial waves
Authors: Ferrett Samantha , Wolf Gabriel , Methven John , Frame Tom , Holloway Christopher , Martinez-Alvarado Oscar , Woolnough Steve
Published: March 2024

Recent work within the WCSSP FORSEA project and its successor FORWARDS has demonstrated that a hybrid statistical-dynamical forecasting technique combining model ensemble forecasts of equatorial waves with climatological rainfall statistics conditioned on wave phase and amplitude can provide additional skill in predicting high impact weather. The underlying rationale for the technique is twofold. Firstly that high impact rainfall events in the tropics are commonly associated with presence of equatorial waves; and secondly that while global models can adequately predict the evolution of dynamical structure of equatorial waves on time-scales of several days they do not predict the relationship between waves and rainfall well. In tests using the Met Office Global and Regional Forecasting System (MOGREPS) the hybrid forecast is found to outperform model rainfall forecasts from both the global and regional convection permitting versions of MOGREPS, however a weighted blend of the MOGREPS forecasts and the hybrid forecast was found to have the highest skill and further improvements in the method may be obtained by taking into consideration the effects of wave-superposition and interaction. To ascertain whether forecasts can be further improved by better predictions of wave amplitude and phase we compare to hypothetical best-case hybrid forecast computed using wave amplitudes and phases taken from reanalysis. This best-case scenario indicates that errors in forecasting all wave types diminish the hybrid forecast's skill, with the most significant reduction observed for Kelvin waves, suggesting that a significant improvement in the prediction of the propagation of equatorial waves would have a significant impact on rainfall prediction in the tropics. 
Arctic peat fire emissions estimated from satellite observations of fire radiative power
Authors: Kaiser Johannes , Stebel Kerstin , Schneider Philipp , Huijnen Vincent
Published: March 2024

Exceptional wildfire activity occurred in the Arctic during the last years due to pronounced heat episodes. The Arctic has an abundance of peat and soils with organic content. When peat is burnt, the carbon flux into the atmosphere is virtually irreversible and this process may become of global significance for Arctic fires. Furthermore, smoke from smoldering fires (below-ground, peat) has a different chemical composition than smoke from flaming fires. It is therefore important to distinguish peat fires and above-ground, potentially flaming fires in fire emission estimation.The operational Copernicus Atmosphere Monitoring Service (CAMS) is tracking global fire activity and emissions with its Global Fire Assimilation System (GFAS) as a near-real time service. GFAS uses satellite-based observations of fire radiative power (FRP), which links observed thermal radiation directly to the biomass combustion rate, i.e. amount of biomass burnt and corresponding emission of carbon into the atmosphere, based on satellite retrievals from MODIS and VIIRS. Here, we present a partitioning of the Arctic fire activity represented in GFAS into smoldering below-ground and potentially flaming above-ground fires using two approaches: (1) masking the fire activity maps with published peat maps and (2) analysing the observed diurnal cycles of the fire activity at all locations. We subsequently apply adapted emission factors and compare the resulting emission estimates to the standard values produced by CAMS for carbon, carbon monoxide, nitrogen dioxide and aerosols.Furthermore, we may confront the fire emission estimates with independent atmospheric smoke observations by feeding them into IFS-COMPO, which is used to generate hindcasts of atmospheric composition, including tropospheric columns of CO and NO2. This allows an evaluation of the estimated trace gas emissions, by comparing the model simulations to satellite retrievals of carbon monoxide and nitrogen dioxide. It thus provides an independent assessment of the estimated fire emissions, and, in turn, carbon flux.
Valve isolation placement to mitigate contaminant spreading in water distribution network
Authors: Santonastaso Giovanni Francesco , Di Nardo Armando , Greco Roberto
Published: March 2024

A water distribution network (WDN) is a complex system that supplies drinking water from water treatment plants to consumers. WDN consists of various elements that ensure an efficient and reliable water supply. Among all these elements, valves are critical components that control the flow and pressure within the network and can isolate segments (the smallest parts of the WDN that can be isolated without interrupting service in the entire WDN) for maintenance or repair purposes. There are several studies in the literature on the optimal positioning of valves, in general the proposed methods are treated as optimization problems with one or more objectives aimed at reducing installation costs while ensuring high system reliability of the WDN (Creaco et al., 2010).In recent years, water distribution networks have become increasingly vulnerable to contamination risks (WHO, 2014). Various factors contribute to this vulnerability, such as malfunctions in chlorination equipment, low pressure, contaminants entering water tanks and inadvertent connections between drinking and non-drinking water sources. When contamination is detected, the quickest remedial action that a water utility can take is to isolate the water section by closing gate valves.The objective of this study is to find the optimal placement of gate valves in the water distribution network (WDN) to address the vulnerability of water quality, effectively isolate the contamination and minimize the residual concentration of contaminants. The proposed methodology is based on community detection algorithms used by sociologists to detect community structures in social networks (Traag, 2014). A community C can be described as a group of nodes with a high density of links between them and low density of links between different groups (or communities).In this work, the community detection algorithm proposed by Girvan and Newman (2002) is used to identify groups of densely connected nodes in the WDN, and then isolation valves are placed on the boundary pipes between the different groups of nodes without performing hydraulic simulations. Different edge weights are tested to improve the placement of the isolation valves and reduce the risk of water pollution. The proposed methodology will be tested on a real water distribution network in southern Italy. ReferencesWorld Health Organization. (2014). Water safety in distribution systems. World Health Organization. https://apps.who.int/iris/handle/10665/204422Creaco, E., Franchini, M. & Alvisi, S. Optimal Placement of Isolation Valves in Water Distribution Systems Based on Valve Cost and Weighted Average Demand Shortfall.  Water Resour Manage 24, 4317–4338 (2010)Traag, Vincent. 2014. Algorithms and Dynamical Models for Communities and Reputation in Social Networks. Springer International Publishing.Girvan , M. E. J. Newman, Community structure in social and biological networks, Proc. Natl. Acad. Sci. 99(12) (2002) 7821–7826.
Shifting nitrate seasonality along decades of anthropogenic impact in western European catchments
Authors: Ebeling Pia , Dupas Rémi , Abbott Benjamin , Kumar Rohini , Ehrhardt Sophie , Fleckenstein Jan H. , Turner Nils , Musolff Andreas
Published: March 2024

Nitrate pollution in streams, although attempts have been made to combat it, remains a persistent problem, especially in highly anthropogenically impacted landscapes such as Western Europe. Nitrate concentrations and discharge typically vary with the seasons, as does the vulnerability of water bodies to high nitrate inputs. However, the degree of variability and seasonal timing vary in space and time while nitrate inputs in catchments have undergone drastic long-term changes. The changing N sources and distribution in the catchments and their variable hydrological activation suggest that different nitrate seasonality has emerged across catchments over the decades. In this study, we hypothesize that nitrate concentrations respond faster to changes in input during the high-flow season than during the low-flow season, as shallow sources are typically activated during high flow and are the first to be affected by changes in management. To test this hypothesis, we propose a hysteresis approach of long-term nitrate seasonality during low- and high-flow seasons, which we applied in 290 catchments in Germany and France with nitrate and discharge time series of 20 or more years. Our results show that in the majority of catchments, nitrate and discharge vary synchronously with peaks in winter. Deviating average nitrate-discharge typologies could be linked to topography and hydroclimatic seasonality as well as to the regionally characteristic source heterogeneity and lithology in northwestern France. Contrary to our hypothesis, we found both types of trajectories with preceding high-flow and low-flow nitrate concentrations were equally present. We could exemplarily show high-flow concentrations responded first in an agricultural catchment and low-flow concentrations reacted first in a more point source intense catchment. However, across the large number of catchments, consistency was not observed suggesting higher complexity of interacting processes. In a further step, we plan to investigate the long-term trajectories of phosphorus to account for the ratios of the major nutrients affecting the resulting impact of land-stream transfer processes on eutrophication.References: Ebeling, P., Dupas, R., Abbott, B., Kumar, R., Ehrhardt, S., Fleckenstein, J. H., & Musolff, A. (2021). Long-term nitrate trajectories vary by season in Western European catchments. Global Biogeochemical Cycles, 35, e2021GB007050. https://doi.org/10.1029/2021GB00705