bluuebunny/crossref_metadata_2025 huggingface dataset:
Storm Tracks and Jet Streams in ICON: Unravelling Climate Change Responses through Aquaplanet Horizontal Grid Spacing Sensitivity Experiments
Authors: Peinado Bravo Angel , Shaw Tiffany , Klocke Daniel , Stevens Bjorn
Published: March 2024

General Circulation Models (GCMs) are widely used to understand our climate and to simulate and predict the effects of global warming, revealing the dynamical convergence of storm tracks and jet streams at horizontal grid spacing of 50 km (e.g., Lu et al. 2015). Nevertheless, they have shown persistent biases in the large-scale features of the general circulation and basic climate statistics, which are attributed mainly to the parameterization, specifically, convection parameterization. To address this, Global storm-resolving models (GSRMs) provide an alternative approach to parameterization by explicitly resolving convection and its interaction with other processes,  through the refinement of the horizontal grid, thus, offering new insights into the climate system. In a prior study, we showed the physical convergence of the tropical and general circulation structure at horizontal grid spacing of 2.5 km using aquaplanets. However, questions linger: Does the response under climate change of the storm tracks and jet streams converge at similar horizontal grid spacing, and what mechanism controls this convergence? We will present the effect of increasing horizontal grid spacing on the convergence of the storm tracks and jet stream location and intensity using the global storm-resolving model ICON. Control runs and idealised climate change experiments (increasing sea-surface temperature by 4 Kelvin) were conducted at horizontal grid spacing from 160 km to 2.5 km using an aqua-planet configuration. We adopt an aqua-planet configuration to focus on atmospheric phenomena, specifically convection and cloud feedback, meanwhile reducing the effect of complex interaction with land, topography, sea ice, and seasons. We will discuss the convergence rate of the eddy driven jet, subtropical jet, storm track, and large-scale circulation and their response to climate warming, characterised by the location, width, and intensity. 
Can appropriate assessment drive hydraulic risk management towards nature-based solutions? A case study in a Natura 2000 site in central Italy.
Authors: Di Cintio Riccardo , Bollati Simone , Rossi Carlo Maria , Luzi Giulia , Antonelli Giuseppe , Antogiovanni Angela , Forcina Francesco , Mancini Massimo , De Simone Simone , Di Biasio Armando , Nardone Antonio , Esposito Sandro , Sabatini Gianluca
Published: March 2024

Flooding is a natural hazard stemming from heavy rainfall, with a growing global impact due to shifts in land use, particularly urbanization and climate change. Traditional flood damage control methods have predominantly relied on “grey” solutions, involving extensive use of concrete structures, either reinforced or not. The sustainability paradigm has prompted a shift towards solutions inspired by nature, where ecological approaches are integrated with engineering design to enhance risk management. In this context, striking a harmonious balance between the “security objective” and biodiversity preservation, especially in areas governed by the European Council Directive 92/43/EEC, emerges as paramount.This case study focuses on the hydraulic-integrated environmental restoration of the Rio Santa Croce stream, partially encompassed within a Natura 2000 site (code IT6040024), located in Latina, Italy (Lat. 41.27°N, Long 13.71°E WGS 84). It serves as an illustrative example of how the Natura 2000 network, often perceived merely as a restriction by authorities, technicians and local communities, can be transformed into a valuable tool for steering hydraulic risk management towards nature-based solutions (NBSs). This transformation could be achieved through the appropriate assessment (AA) regulated by Article 3 of the European Council Directive 92/43/EEC.A multidisciplinary team, comprising professional foresters from the Società Cooperativa Trifolium a.r.l., along with professional engineers and a professional geologist, on behalf of the Province of Latina, conceived a green gabion wall to stabilize the banks of a section of the Rio Santa Croce while creating habitats for aquatic vertebrates. These retaining structures are considered environmental-friendly, offering a more sustainable option compared to traditional earth-retaining walls. By integrating vegetation and implementing special technical measures during the assembly of the baskets, the gabion wall can be classified as NBSs, providing a favorable compromise in situations where the only alternative involves conventional grey solutions. 
Interpretable Machine Learning to Understand Multi-Scale Meteorological Impacts on Ecosystem Carbon Uptake
Authors: Hafezi Rachti David , Reimers Christian , Winkler Alexander J.
Published: March 2024

Terrestrial carbon uptake constitutes the main driver of interannual variations in atmospheric CO2 and thus one of the least understood parts of the global carbon cycle. Meteorological factors, such as variations in weather patterns and extreme climate events, are the main drivers of interannual variations in the land carbon uptake. Assessing these impacts of meteorological events on the annual carbon balance, in terms of their timing and duration and their interaction with ecosystems, remains a challenging problem. Here we propose a data-driven approach to shed light on the meteorological drivers of terrestrial carbon variability. We use a convolutional neural network to predict carbon and water fluxes in forest ecosystems, which is trained on wavelet-transformed key meteorological variables to explicitly represent a wide spectrum of time-scales in the input. We curate a dataset conflating eddy covariance data from 15 deciduous broadleaf forest sites from the FLUXNET network, meteorological measurements gap-filled with reanalysis data and a random walk variable for validation. The application of an explanatory machine learning technique provides insights into the importance of the different meteorological events in terms of their length and timing in controlling anomalies in the annual terrestrial carbon balance. Additionally, we test our approach trained on carbon and water fluxes output from a comprehensive land-surface model to evaluate the validity of the observation-driven model. The model shows that water availability is the dominant factor of local variations in the carbon balance. In particular, vapour pressure deficit events lasting 20-40 days in summer are one of the most important drivers for the model to predict a lower annual carbon uptake. Furthermore, we compare these quantitative results and results of a case study of the 2003 heatwave with the model setup trained on land-surface model output. Such studies are important to demonstrate the potential of interpretable machine learning methods to improve our understanding of land-atmosphere interactions, and crucially, to learn the complex responses of ecosystems to meteorological variability from data.
Seasonal and temporal drivers of carbon and nutrient export from Finnmark rivers: Results of a 23-year time series of water chemistry and satellite imagery from Northern Norway
Authors: McGovern Maeve , Karlsen Stein , Høgda Kjell , Demars Benoît
Published: March 2024

In the Arctic, climate change impacts on terrestrial ecosystems have the potential to affect the magnitude and timing of carbon and nutrient export from soils to freshwaters and the coastal ocean, with implications for the structure and function of receiving aquatic ecosystems. For example, temperature driven increases in vegetative biomass, ‘Arctic greening’, may lead to increased export of dissolved organic matter, yet reduced export of inorganic nutrients, from catchments to surface waters, with implications for aquatic food-webs and biogeochemical cycling. Meanwhile, changes in seasonality on land (e.g. timing of leaf-out and autumn onset) can impact the timing of organic and inorganic matter inputs to surface waters, with potential for asynchrony with aquatic ecosystem processes. We compiled a 23-year time series (2000-2023) of monthly water chemistry monitoring data and satellite imagery (e.g. ndvi, snow cover, leaf-out, autumn onset) from the Alta, Tana and Pasvik rivers in Finnmark, Northern Norway. In addition, for the Tana River, we paired these long-term monthly water chemistry observations with 2 years (2022, 2023) of high resolution data collected from a network of in-situ sensors across a gradient in land cover types. Using concentration-discharge relationships and statistical modelling of element fluxes across multiple spatial and temporal scales, we investigated the importance of vegetation, climate, and hydrology as drivers of temporal and seasonal carbon and nutrient export from Finnmark rivers. Here, we present preliminary results and discuss implications for downstream aquatic ecosystems.
Mitigating Urban Heat Island Intensity in Urban Environments by optimal control method
Authors: Mouhali Waleed , Sellila Nacer , Louaked Mohammed , Mechkour Houari
Published: March 2024

Climate in urban areas differs from that in neighboring rural areas, as a result of urban development. It can create issues. Among these disturbances, Urban Heat Island (UHI) is a huge risk with many negative consequences (health, comfort...). It concerns urbanized area where temperatures are higher than in surrounding areas. To reduce this effect, the implantation (and design) of green spaces in dense cities is a pertinent solution.In this study, we use optimal control method to find the optimal shape of green space. We consider city as a porous media system. Therefore, a three-dimensional model is established for numerical studies of the effects of urban anthropogenic heat and wind velocity in urban and rural regions. The transport mechanism of fluid in the cities is governed by the Navier–Stokes–Forchheimer porous media system. It is actually based on non-stationary turbulent fluid dynamics coupled with heat equation considering building/soil radiation effects. We compute two-dimensional direct numerical simulation. We show the results for temperature and velocity fields. This work presents the governing equations, the control optimal algorithm and discusses the results of the predictions of the flow problems constituting the initial validation space of the model.
Shall I compare thee to a distant world? The importance of inter-planet and inter-model comparative studies.
Authors: Sergeev Denis
Published: March 2024

We cannot truly understand the general principles that govern planetary processes by studying only one planet or using only one modelling framework. Fortunately, continuing leaps in solar system exploration and recent exoplanetary discoveries, accelerated by the advent of JWST, allow us to start drawing connections between solar system planets and exoplanets — applying the vast knowledge of Earth and its neighbours to more distant worlds, and vice versa. To this end, solar system objects can offer analogues of some of the more exotic exoplanets, e.g. Jupiter's moon Io as an ultra-hot geologically active rocky planet analogue, or Venus as a habitable-zone Earth-like planet with a decidedly non-Earth climate. Within the solar system itself, a lot of atmospheric and geologic phenomena are present on more than one planet: dust devils are observed on both Earth and Mars, Earth's hydrological cycle has its methane counterpart on Titan, to name but a few. On the other hand, expanding our understanding of exoplanets places our own solar system within the broader context of planetary formation, architectures, atmospheres, and habitability. At the same time, a smorgasbord of numerical models, including 3D general circulation models of the atmosphere, are now routinely being applied to different planets, both to test our theory, predict and interpret observations. Drawing from the success stories in the Earth climate community, it is now recognised that benchmarking and comparing the behaviour of numerical models through intercomparison projects is one of the key ways to advance our knowledge. This has a variety of benefits to the planetary science, from better planning for future observations to identifying bugs in the code to feeding back the model improvements to the Earth climate community. Recently, this effort has been re-invigorated under the CUISINES framework, an international effort to systematically contrast and compare models of various complexity for a range of different planets. In this talk, I will first demonstrate how a state-of-the-art 3D climate model can be used to study different planetary atmospheres, from extrasolar hot Jupiters to temperate rocky planets. Using this model as an example, I will discuss some lessons that can be learnt in building planetary climate models. I will then give some highlights of the recent model intercomparisons for exoplanets and solar system planets. I will conclude with a discussion on how model intercomparison projects benefit both planetary and Earth-focused science.
Web-Based Severity Assessment of Natural Hazards: Natural Language Processing Based Extraction of Severity Impact Factors for Informed Decision Support
Authors: S Gopal Lakshmi , Thirugnanam Hemalatha , Vinodini Ramesh Maneesha , Malamud Bruce D.
Published: March 2024

This study introduces an automated information extraction (IE) method for assessing natural hazard severity using online sources (news articles and social media). A web crawler collects 4-15 daily news articles from diverse web sources, amassing 4,000 reports on natural hazard events between 05/2020 and 11/2023, while adhering to respective web page privacy rules. The extracted data analyses hazard severity, focusing on the impact factors of casualties and damages. This analysis aids decision-makers and researchers in comprehending the impact of hazards and developing mitigation strategies. Real-time web data severity analysis can also support first responders in resource allocation during and post-disasters.A natural language processing-based algorithm identifies hazard impact factors using grammatical patterns, PoS (Parts of Speech) tagging, and NER (Named Entity Recognition). From these, we identify numeric values for casualties, infrastructural and financial damages and public necessities, along with place names. The data is structured in a database for analysis.We utilize TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution), a Multi-Criteria Decision-Making method, to assign a severity rank to each location. In TOPSIS, we define the positive ideal solution as the maximum values for positive attributes (e.g., number of rescue operations, people rescued, and government authorities’ involvement). The negative ideal solution represents the minimum values for negative attributes (e.g., damages and fatalities) in each criterion. We then calculate relative closeness (0.0 to 1.0) by measuring each criterion’s distance from the positive and negative ideal solutions. A higher relative closeness indicates less severity, while a lower value suggests greater severity in hazard events. This rank aids in identifying the area with the highest severity, enabling first responders to allocate resources effectively by prioritizing the locations with the most significant impact. Each location’s severity rank is based on relative closeness to positive and negative ideal solutions.We apply our methodology to the 2018 Kerala, India floods, using 200 news reports (national and local news portals, blogs), identifying the Alappuzha district as the most severely affected (highest severity score) and the Kasargod district the least affected (lowest severity score). Agricultural loss emerges as a significant factor, emphasizing the need for sustainable solutions. Results are consistent with official Kerala State Disaster Management Authority documentation, demonstrating the methodology’s accuracy. Our methodology provides near real-time information for identifying and prioritizing severely affected areas, aiding efficient resource allocation, rehabilitation efforts, and post-disaster decision-making.
Establishing ecological baselines for benthic communities in the southern Gulf of Trieste (northern Adriatic Sea) using molluscan death assemblages
Authors: Pavlović Matej , Nawrot Rafał , Steger Jan , Mavrič Borut , Zuschin Martin
Published: March 2024

The northern Adriatic Sea is one of the most degraded marine ecosystems worldwide and has been under anthropogenic influence for many centuries. Reconstructing pre-human impact benthic communities is vital to establish baseline conditions, allowing a better understanding of how anthropogenic activities and climate warming have influenced and altered marine ecosystems over time. This historical context helps to assess the extent of anthropogenic influence, guiding future conservation efforts and management strategies.Our primary goal is to uncover the composition of pre-human impact benthic communities on the shallow shelf along the Slovenian coast (Gulf of Trieste) and to reconstruct the natural state of these habitats.This investigation involved systematic grab sampling of subtidal soft substrates across three distinct areas, encompassing eight stations in the Bay of Koper and Bay of Piran, at water depths ranging from seven to ten meters. We focus on analyzing the composition of mollusc death assemblages, time-averaged accumulations of empty shells present in the uppermost mixed layer of seafloor sediments. Due to high durability of these skeletal remains and generally low sedimentation rates in shelf environments, death assemblages integrate shells over time spans of decades to millennia, making them valuable natural archives of past community states. Our results show that samples collected near the major port of Koper are strongly dominated by the opportunistic and stress-tolerant bivalve Varicorbula gibba, and show significantly lower species richness compared to stations located further away from this potential source of environmental disturbance. Moreover, assemblages from the protected area of the Debeli rtič are compositionally distinct from those of other areas. These patterns likely reflect the combined effects of differential levels of anthropocentric impacts, as well as differences in substrate characteristics and the magnitude of time averaging of the death assemblages among sampling stations.The obtained community data will be cross-checked with live assemblage data based on the systematic benthic monitoring efforts conducted over the last 15 years (2005–2020) to ascertain changes in the mollusc community. The examination of modern and historic data will provide a robust long-term baseline that is essential for understanding and quantifying the impacts of significant human-induced modern stressors on the northern Adriatic marine ecosystem.
Showcasing Advances in Climate Prediction and Early Warning Systems in the Greater Horn of Africa
Authors: Bahaga Titike , Segele Zewdu , Endris Hussen , Mwanthi Anthony , Gudoshava Masilin , Koech Eunice
Published: March 2024

The Greater Horn of Africa (GHA) region is most vulnerable to climate-related risks. The effects of climate change have become increasingly evident in the region through a rise in the frequency and intensity of extreme weather and climate events, notably recurrent and severe droughts, floods, landslides, and tropical cyclones. These extreme climatic events have had far-reaching consequences on the key socio-economic sectors. The extended drought experienced in 2020/2022 led to the loss of millions of livestock and plunged millions of individuals into poverty, prompting forced displacement and insecurity. In contrast, the strong El Niño and positive Indian Ocean Dipole (IOD) events in 2023/2024 brought substantial rainfall to Somalia, Ethiopia, and Kenya in October and November 2023, resulting in flooding that has caused the loss of over 100 lives and displaced more than 700,000 people. Thus, providing reliable and timely climate information is essential for climate services and is increasingly crucial in supporting decision-making processes across a range of climate-sensitive sectors and reducing extreme climate impact. The IGAD Climate Prediction and Applications Centre (ICPAC), as a World Meteorological Organization (WMO) Regional Climate Centre (RCC), currently performs the mandatory and recommended RCC functions covering the domains of climate monitoring, climate forecasting, capacity development, and generation of regional and sub-regional tailored products relevant to the various socio-economic sectors. ICPAC has developed improved and tailored climate products and innovative decision support tools to enhance early warning services. It is also one of the first RCCs to adopt the objective forecasting technique and produce a traceable, reproducible, and verifiable forecast based on WMO’s recommendation. Innovative approaches to user engagement through co-production, communication channels, user-friendly interfaces, and dissemination of climate information have also been developed. In this session, we would like to showcase the innovative early warning methods, products, services, and platforms developed by ICPAC for response planning and anticipatory actions to enhance community resilience in the GHA region. This includes improved objective forecasting methods for monthly and seasonal forecast products, innovative approaches to user engagement through co-production, communication channels, and sector-tailored products (onset, cessation, dry and wet spells, probability of exceedance). 
Mission operations – enhancing the success of analogue missions through the Remote Science Support (RSS)
Authors: Knie Julia , Özdemir-Fritz Seda Özdemir-Fritz , Savic Jelena
Published: March 2024

Analogue missions serve as valuable models for simulating and testing scenarios for human space exploration in a terrestrial environment. The success of these missions relies on the seamless collaboration of diverse teams, each playing a crucial role in different phases of the mission lifecycle.  Among those teams the Remote Science Support (RSS) group, stationed at the Mission Support Center (MSC), stands out as an anchor connecting experts, scientists, and mission control center with analogue astronauts in the field.The RSS plays a pivotal role in supporting Principal Investigators (PIs) throughout the entirety of the pre-mission, in-mission, and post-mission phases. During the pre-mission phase, the RSS team collaborates closely with PIs to fine-tune experiment parameters, ensuring their alignment with mission objectives and the unique challenges posed by analogue environments. The RSS team serves as a critical liaison, facilitating seamless integration of experiments into the analogue mission framework. In the synchronous (syn) mission phase, RSS operates in near real-time, providing immediate guidance and insights to astronauts as they execute experiments. This dynamic support ensures the optimization of decision-making processes and the resolution of mission-critical issues. Transitioning to the post-mission phase, RSS continues its support by facilitating data validation and scientific post-processing. By offering valuable insights and analysis, RSS assists PIs in refining future experiments and advancing their research agendas. This comprehensive support across pre, syn, and post-mission phases underscores the integral role of RSS in maximizing the scientific yield and success of analogue missions.Communication delays, technological constraints, and the need for adaptable protocols present challenges for RSS. Recognizing the importance of these challenges, this study identifies strategies for mitigating them, emphasizing the need for interdisciplinary collaboration. Effective communication between the RSS team, Mission Support Center, and on-field astronauts becomes significant for overcoming these challenges. Continuous refinement of mission operations procedures is essential to ensure that the RSS remains a dynamic and responsive support system throughout the mission lifecycle.The findings presented, contribute to the growing body of knowledge on analogue missions and underline the fundamental role of RSS in advancing human space exploration capabilities. As space agencies and research institutions continue to invest in analogue missions as a precursor to actual space expeditions, optimizing RSS mechanisms becomes paramount for achieving mission success and ensuring the safety and productivity of future astronauts.
Automatic analysis of shoreline dynamics on Sentinel-2 datasets using CoastSat software toolkit
Authors: Toma Andrei , Sandric Ionut , Mihai Bogdan , Scrieciu Albert
Published: March 2024

Shorelines, as interfaces between land and water, are subject to continuous transformation due to various natural phenomena and human-induced activities. Natural processes, such as erosion and sedimentation play an important role in shaping coastal areas, while human activities, like urban expansion, also exert a significant stress on coastal areas. An illustrative instance of human-induced changes is exemplified by the Mamaia beach enlargement project, which was initiated along the coast of Romania at the Black Sea by the end of 2020 and executed throughout 2021. The analysis of this coastal transformation started in 2020, preceding the actual implementation of beach enlargement, and extended until late 2023. This timeframe was selected to capture the entirety of the dynamic changes that can be observed in the study region. Utilizing the advanced multi-temporal CoastSat toolkit, the analysis involved a detailed examination of 130 high-resolution images acquired by Copernicus Sentinel-2 satellites. Implemented within a Jupyter notebook environment using Python, CoastSat showcased its efficacy in extracting shorelines from the multi-temporal dataset, enabling a thorough understanding of the coastal dynamics observed in the Mamia beach enlargement project. The analysis reveals an expansion of over 200 m on the southern part of Mamaia beach. This transformation underscores the significant impact of human activities, emphasizing the need for sustainable coastal management practices in the face of evolving environmental challenges.
From conceptual to complex earth system models: why are models so linear?
Authors: Brovkin Victor , Stacke Tobias , de Vrese Philipp , Kleinen Thomas , Winkler Alexander
Published: March 2024

The evolution of the Earth’s climate from the past to the future is explored by a hierarchy of models ranging from conceptual models to full-complexity, high-resolution Earth System Models (ESMs) (Claussen et al., 2002). The strength of conceptual models lies in the clarity of representing the concept of interactions between different climate processes, while ESMs  offer greater realism when it comes to spatial or temporal detail. Intermediate complexity models are somewhere in between, they are able to provide a big picture for long timescales. A common pattern throughout the model hierarchy, except for conceptual models illustrating multiple steady states, is often linearity of model responses to external forcing. This linearity can be visible in transient experiments, but also in equilibrium simulations. The question arises: is this linearity an artefact of our models, or is it reflective of reality? In most cases, the linear response is likely representative of reality. As an example, we will focus on the linearity of land-related processes, such as climate-carbon feedbacks and permafrost-hydrology interactions. Permafrost systems have thresholds at 0°C, leading to nonlinearities at the local scale, but the combined response at large spatial scales tends to be more linear. However, nonlinear and abrupt changes are evident in geological records. For instance, the abrupt onset of the Bölling/Alleröd warming about 14.8 thousand years ago indicates that nonlinear changes on large spatial scales are indeed a real, albeit very rare, phenomenon. We will discuss possible reasons for the predominant linearity of the models and explore whether high-resolution models might show more nonlinear responses than coarse-grid models. Reference:Claussen, M., Mysak, L., Weaver, A. et al. Earth system models of intermediate complexity: closing the gap in the spectrum of climate system models. Climate Dynamics 18, 579–586 (2002). https://doi.org/10.1007/s00382-001-0200-
New geomaterial for energy storage - mechanical and thermal properties 
Authors: Kołodziej Konrad , Lutyński Marcin , Pierzyna Piotr
Published: March 2024

The development of renewable energy sources requires the development of technologies and further expansion of energy storage infrastructure on global markets. One type of energy storage is thermal energy storage(TES). Ongoing researches aim at improving the efficiency of storage and heat transfer in such installations. An important element of these installations is the reservoir that accumulates thermal energy. The following work presents research on new geomaterials based on waste materials, mining raw materials and mixed materials based on them, which could potentially be used as materials for the construction of a packed bed or resevoir that stores thermal energy in TES. These materials, due to the possibility of forming almost any shapes, should exceed the efficiency of aggregate minerals. Additionally, their utilization can partially or fully eliminate mining waste, thereby promoting circular economy principles. 
A toolbox approach to measuring carbon stocks and sequestration in the North Sea
Authors: Powell Claire , Graves Carolyn , Dal-Molin Franck , Garcia Clement , Hynes Clare , Limpenny Caroline , Mason Claire , Nelson Paul , Smeaton Craig , Parker Ruth
Published: March 2024

Understanding the capacity of marine sediments to store and sequester atmospheric carbon is an essential first step in assessing the possibilities for the management of these stores, including management of pressure such as bottom contacting fisheries, and addressing policy questions such as their potential as nature-based solutions to climate change. Using a toolbox of complimentary techniques for determining carbon abundance, provenance and reactivity, accumulation rates and vulnerability we have analysed a total of 18 sediment cores taken from sites across the North Sea during February and December 2021. Additionally, we have preliminary results from an additional 40 cores taken from a range of sites across the North Sea in June 2023, including across trawling gradients.We present results from our toolbox approach, measuring the carbon stock and sequestration for the cores using a suite of complimentary analyses: from novel techniques such as alkane biomarkers and thermogravimetric analysis (TGA), to radiometric determination of sedimentation rates by lead-210 and stable carbon isotopes (δ13C) in bulk organic carbon, to the more routine techniques such as particle size distribution (PSA), organic & inorganic carbon and nitrogen, porosity, chlorophyll/phaeopigment, and black carbon. We show how viewing the results together can increase the understanding of how carbon is processed in the seabed at a regional scale, and how this can inform where management measures would be most appropriately applied.
The Spatial Treeline-Ecotone Model (STEM) as a tool for understanding pattern-process relationships in alpine-treeline ecotones
Authors: Bader Maaike , Flinspach Lukas , Case Bradley , Camarero Julio , Wiegand Thorsten
Published: March 2024

Spatial patterns in alpine-treeline ecotones reflect the ecological processes that have shaped and probably continue to shape these transition zones. Understanding these processes is essential for predicting treeline responses to global-change factors. To connect treeline-ecotone patterns and processes, we developed a spatially-explicit individual-based model. The first version of this Spatial Treeline Ecotone Model (STEM 1.0) represents the growth, mortality and dieback (biomass loss leading to stunted trees or krummholz) of all individual trees within a treeline transect, and uses variation in these demographic rates, imposed along elevation gradients or emerging as a result of neighbor interactions, to create treeline ecotones with different spatial patterns. The model could reproduce many of the expected treeline types, but some types required very particular parameter combinations. These results helped to identify missing elements in the model and thus to sharpen our conceptual model of treeline-forming processes. The next mayor development step for the model is to let demographic rates emerge from the interaction of environmental influences, modified by plant-plant interactions, rather than being imposed. However, this first version is a very important first step to formalizing and developing our conceptual model of pattern-process relationships in alpine-treeline ecotones.
Numerical simulation of dike breaching by overtopping. Influence of the bank erosion operator. 
Authors: Jonatas Ricardo , L Ferreira Rui M , Ricardo Ana M , Amaral Sílvia
Published: March 2024

We employ a physically-based in-house 2D multi-layered depth and time averaged shallow water model with the capacity to simulate morphology and sediment transport (HiSTAV) to model the erosion of dikes subjected to overtopping. Its conceptual model is based on conservation laws for shallow flows and requires closures for flow resistance, and sources and sinks of transported substances. The conservation laws are discretized within a Godunov-type Finite Volume scheme. HiSTAV design is entirely cross-compatible between CPUs and GPUs, through an intuitive object-oriented approach. HiSTAV requires the parametrization of the processes expressing hydraulic erosion, slope failure and mass detachment. The latter are modelled as sudden collapses of cells of dam body, dry but adjacent to the flow, a process akin to river bank collapse. A secondary mesh is defined to group the cells that form the detached mass. We investigate the effects of the dimension of the group and the values of the parameters (velocity and shear stress) that trigger the collapse. As expected, the bulk erosion rate increases with the size of the detached group. The results of the model were compared with data from laboratory models. Three laboratory tests were carried out in a medium-scale facility located at the Fluvial Facilities of the Hydraulics and Environment Department (DHA) of LNEC. The facility operates in closed circuit and is composed by a 1.40 m wide and 19 m long channel where the river stream is simulated. It allows testing dikes up to 0.50 m height and 2.0 m long. The water level upstream the dike is controlled by a sluice gate placed at the downstream end of the channel. The dike site and the main channel where constructed in an elevated platform, after which there a settling basin (2.10W x 4.5L (m)) where the eroded soil from the failure tests is deposited. A Bazin spillway exists at the end of this structure to measure the dike outflow discharge. We performed 3-D reconstructions of the evolving dike geometry, monitored the water levels in the main channel, the flow discharges in the main channel and across the breach and calculated the surface velocity fields in the vicinity and breach (LSPIV). The rate of breach erosion and the velocities near the breach were compared with the results of the model. It was observed that the size of the detachment group should scale with the breach crest and is influenced by the type of soil.Acknowledgements: This work was partially funded by the Portuguese Foundation for Science and Technology (FCT) through Project DikesFPro PTDC/ECI-EGC/7739/2020 and through CERIS funding UIDB/04625/202
Overview of the Theme 2 of IAHS HELPING: Holistic Solutions for Water Security 
Authors: Mijic Ana , Teutschbein Claudia , Finger David , Liu Junguo , Foerster Kristian , Wens Marthe , Bezak Nejc , Palmate Santosh , Nishad Shiv , Krause Stefan
Published: March 2024

The term "water security" denotes the sustainable availability and access to clean and safe water for diverse purposes, ensuring the well-being of individuals, communities, and ecosystems. Despite numerous proposed solutions from the scientific community to address water security challenges, a genuinely holistic, systems-level approach is still lacking. The research conducted under Theme 2 of the new IAHS HELPING decade is grounded in the premise that holistic solutions for water security necessitate an integrated approach. This involves understanding the potential and challenges associated with mitigation methods for floods, droughts, and water quality/pollution, as well as being aware of the sectorial nexus of problems and solutions. Nature-based solutions (NBS) are also considered for sustainable water management. The theme brings together seven working groups (WGs) focusing on methods and applications for characterising droughts in the Anthropocene, providing near-term water availability forecasts, and conducting water systems analysis using integrated tools and participatory engagement. Additionally, these WGs address interactions between water, energy, health, and ecological systems, with the aim of advancing ecological restoration and the implementation of NBS. This talk will present a high-level overview of the WGs, showcase preliminary findings, and discuss the potential for integrating insights and methods from multiple work streams into a comprehensive framework for water security solutions.
Temporal Interpolation of Sentinel-2 Multispectral Time Series in Context of Land Cover Classification with Machine Learning Algorithms
Authors: Simon Mate , Richter-Cserey Mátyás , Pacskó Vivien , Kristóf Dániel
Published: March 2024

Over the past decades, especially since 2014, large quantities of Earth Observation (EO) data became available in high spatial and temporal resolution, thanks to ever-developing constellations (e.g.: Sentinel, Landsat) and open data policy. However, in the case of optical images, affected by cloud coverage and the spatially changing overlap of relative satellite orbits, creating temporally generalized and dense time series by using only measured data is challenging, especially when studying larger areas.Several papers investigate the question of spatio-temporal gap filling and show different interpolation methods to calculate missing values corresponding to the measurements. In the past years more products and technologies have been constructed and published in this field, for example Copernicus HR-VPP Seasonal Trajectories (ST) product.  These generalized data structures are essential to the comparative analysis of different time periods or areas and improve the reliability of data analyzing methods such as Fourier transform or correlation. Temporally harmonized input data is also necessary in order to improve the results of Machine Learning classification algorithms such as Random Forest or Convolutional Neural Networks (CNN). These are among the most efficient methods to separate land cover categories like arable lands, forests, grasslands and built-up areas, or crop types within the arable category.This study analyzes the efficiency of different interpolation methods on Sentinel-2 multispectral time series in the context of land cover classification with Machine Learning. We compare several types of interpolation e.g. linear, cubic and cubic-spline and also examine and optimize more advanced methods like Inverse Distance Weighted (IDW) and Radial Basis Function (RBF). We quantify the accuracy of each method by calculating mean square error between measured and interpolated data points. The role of interpolation of the input dataset in Deep Learning (CNN) is investigated by comparing Overall, Kappa and categorical accuracies of land cover maps created from only measured and interpolated time series. First results show that interpolation has a relevant positive effect on accuracy statistics. This method is also essential in taking a step towards constructing robust pretrained Deep Learning models, transferable between different time intervals and agro-ecological regions.The research has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the KDP-2021 funding scheme. Keywords: time series analysis, Machine Learning, interpolation, Sentinel
Positive Tipping Points in the Food Systems: the Role of Scales
Authors: Tuninetti Marta , Giordano Vittorio , Constantino Sara , Perri Saverio , Rocha Juan , Schwarz Luana , Donges Jonathan F. , Laio Francesco , Levin Simon
Published: March 2024

The global food system is at a critical inflection point with rising awareness of the need for change and progress on several fronts, pertaining both human health and the environment. One of the ten critical transitions envisioned by the Food and Land Use Coalitions states that global diets need to converge towards local variations of the “human and planetary healthy diet” which includes more protective foods a diverse protein supply, and reduced consumption of sugar, salt and highly processed foods. Positive tipping points (PTP) offer a new perspective to support and boost the implementation of solutions for sustainable and healthy food systems. A PTP in the food system can be seen as critical points where targeted interventions lead to large and long-term consequences on the evolution of that system, profoundly altering its modes of operation.  While discussions on food PTP dynamics are an intriguing theoretical debate, we still lack empirical evidence if and how such dynamics unfold in practice, especially in the food sector. Literature on inducing positive tipping and feedback dynamics in sustainability transitions almost exclusively focuses on the energy sector, leaving an important gap in the empirical research on the specific enabling factors for triggering these dynamics in respect to food and global diets transformation.  How do different organizational, geographical, and temporal scales should interact with each other to accelerate a transition to a sustainable food system? In this study we integrate complex network theory tools with systems’ emergent properties to better define multi-scale food systems dynamics. We develop indicators (with country resolution and global coverage) to synthesize the food system’s structure and its weak and strong points where the spread of positive changes can be maximized. This quantitative framework is aimed at supporting the actions of government in repurposed agricultural subsidies, targeted public food procurement, taxes and regulations on unhealthy food; and business in redesigning product portfolio based on the human and planetary health diet. 
Dialogue between technique and administration in volcanic risk management; Data issues
Authors: Brigante Vinicio
Published: March 2024

For years now, proliferation of technological tools has been taking hold, albeit with some resistance, in the public sector since, as reflected in the agendas and public policies of EU member states, digitalization is a non-deferrable need, a prerequisite for the implementation of further reforms. This report’s purpose is to ascertain whether and how, data in AI can support administrations and stakeholders in coping with unforeseen events, such as earthquakes and volcanic eruptions. Among disaster protection risks, volcanic activity is often considered a foreseeable risk because it is thought that phenomena that presage rising magma to surface can be recognized and measured. These phenomena are called precursors although this is a simplification that does not take into account the complexity and extreme variability of volcanic phenomena and the difficulty in assessing and interpreting them. Precursor phenomena, as indicators of an ongoing process that if properly and adequately studied, analyzed and monitored, can give an idea of the state of volcano activity and its possible evolutions, allowing for the detection of possible anomalies. For this reason, data and processing by AIs can provide support and decrease errors in the calculation of phenomena even if only a quantitative reduction. Data and their processing can provide a reliable index to support prevention activities. Potential issues for the jurist involve ownership of database management, interoperability, errors in the management of the same knowledge. Assessment by AI and data has the advantage of being rapid and devoid of operator discretion. Machine learning, in fact, has a capacity of about 98 percent to correctly attribute a rock of unknown origin. Central to the discussion is to determine the ownership of data and the AI tools deputed to process them, whether to endow public facilities, or outsource this function to the private sector.
Precaution and prevention in the jurisprudence of the administrative judge
Authors: Iacopino Annarita
Published: March 2024

This paper aims to analyse the path of administrative jurisprudence on how the principles of prevention and precaution behave, the role they assume for the public decision-maker and the judge's review. In this perspective, priority is given to examining the nature and ratio of the two principles, as well as the relationship between them. It is then necessary to define their sphere of operation and the essentially “methodological and bidirectional” dimension in which they move. They, in fact, offer rules for proceeding and not for deciding, thus allowing the identification of the path of proceduralisation of public decisions in situations of danger (prevention) or in situations of risk (precaution), enabling the minimisation of risks, respectively, through intervention on the causes of the possible emergence of danger and through the identification of the solution that makes it possible to balance the minimisation of risks with the maximisation of benefits. In an emergency phase, as in the case of compulsory vaccination, this may require operating in a “counter-intuitive” manner with the imposition of instruments-therapies- that ensure more benefits than risks, since the potential risk of an adverse event for an individual is far less than the actual damage to society as a whole. In all these hypotheses, the scientific basis represents a guarantee of the reasonableness of the choices, since the public decision-maker's assessment must be based on acquisition of the best science of the moment and on the rigour of the relevant method; a “reserve of science” whose reasonableness and proportionality is subject to the administrative judge's review.