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Cette thèse est basée sur des simulations numériques régionales et aborde, d’un point de vue énergétique, la variabilité à Méso (O(10-100)km) et Sous-mésoéchelle (O(0.1-10)km) dans la région du Courant des Aiguilles.(i) La variabilité de sous-mésoéchelle à la transition entre les deux branches du Courant des Aiguilles (28◦E-26◦E) est dominée, en l’absence de méandres de mésoéchelle, par des tourbillons cycloniques frontaux formant un ‘vortex street’. La tension ambiante frontogénétique intensifie le cisaillement frontal qui déclenche l’instabilité barotrope menant à la génération de tourbillons de sous-mésoéchelle.(ii) Un budget modal d’Energie Cinétique des Tourbillons est développé pour caractériser les transferts d’énergie entre les différentes structures verticales. Les interactions canalisées par la topographie (3 processus) résultent globalement en une perte d’énergie pour les tourbillons de mésoéchelle plus grande que les processus de dissipation (friction au fond et vent) et une cascade verticale inverse (interactions triadiques) renforce les tourbillons de mésoéchelle dans les zones au large.(iii) Notre budget modal permet de caractériser la région du Courant des Aiguilles comme une source nette d’énergie pour les tourbillons de mésoéchelle en contradiction avec celui estimé à partir de données d’altimétrie. Cette différence vient des données d’altimétrie ne tenant pas compte de la contribution principale de la dynamique aux sources et puits d’énergie des tourbillons de mésoéchelle (partie linéaire de la dynamique agéostrophique du mode barotrope et du 1er mode barocline). This dissertation is based on regional numerical simulations and addresses, from an energetic perspective, the Meso (O(10-100)km) and Submesoscale (O(0.1- 10)km) variability in the Agulhas Current region.(i) Submesoscale variability at the transition between the two Agulhas Current branches (28◦E-26◦E) is dominated, in the absence of mesoscale meanders, by cyclonic frontal eddies forming a ’vortex street’. The frontogenetic background strain intensifies the frontal shear which triggers the barotropic instability leading to submesoscale eddies generation.(ii) A modal Eddy Kinetic Energy budget is derived to characterize the energy transfers between the different vertical structures. Interactions canalized by topography (3 processes) globally result in a larger energy loss for mesoscale eddies than dissipation processes (bottom friction and wind) and an inverse vertical cascade (triadic interactions) reinforces mesoscale eddies in offshore areas.(iii) Our modal budget allows to characterize the Agulhas Current region as a net energy source for mesoscale eddies in contradiction with one inferred from altimetry data. The discrepancies come from altimetry data not accounting for the main contribution of the dynamics to mesoscale eddies energy sources and sinks (ageostrophic linear part of the dynamics of the barotropic and 1st baroclinic modes).

• Key message Insurance might be an efficient tool to strengthen adaptation of forest management to climate change. A theoretical model under uncertainty is proposed to highlight the effect, on adaptation decisions, of considering adaptation efforts in forest insurance contracts. Results show that insurance is relevant to increase adaptation efforts under some realistic conditions on forest owner’s uncertainty and risk preferences, and on the observability or not of adaptation efforts. • Context One of the challenges of forest adaptation to climate change is to encourage private forest owners to implement adaptation strategies. • Aims We suggest the analysis of forest insurance contracts against natural hazards as a vector to promote the implementation of adaptation efforts by private forest owners. • Methods We propose a theoretical model of insurance economics under risk and under uncertainty. • Results Our results indicate that when climate change makes the probability of the occurrence of the natural event uncertain, then it may be relevant to include adaptation efforts in the insurance contract, leading to an increase in the adaptation efforts of risk-averse and uncertainty-averse forest owners. In addition, we show that the relevance of insurance as a vector to promote adaptation efforts is greater when the forest owner’s effort is unobservable by the insurer as compared to a situation of perfectly observable effort. • Conclusion Under some realistic assumptions, the forest insurance contract seems to be a relevant tool to encourage forest owners to adapt to climate change.

The EU has set out to reduce negative impacts from electricity generation on the environment, human health and towards our dependence on fossil fuels. As the fastest growing renewable source of electricity, photovoltaics plays an important role in the energy transition. The manufacturing of photovoltaic modules requires materials classified as critical, making them prone to supply disruptions. Although these materials are essential to the EU economy, they are not sufficiently recovered at the end of a photovoltaic module’s life. An alternative intermediate solution could be to extend the lifespan of existing modules, to slow down demand for these materials in the future. The aim of this study was to analyse the theoretical options and practical examples of product life extension strategies for photovoltaics. The R-Ladder was used as a guiding framework, which provided examples of life extension strategies. These include Reuse, Repair, Refurbishment, Remanufacture and Repurpose. Aspects for each of these strategies were analysed to find potential benefits and challenges related to four aspects: economics, environment, energy, and materials. The approach of this study includes a literature review to identify the life extension strategies discussed specifically for photovoltaics in the context of the circular economy. This was followed by a multi-case study on practical applications of Reuse, Repair and Repurposing of photovoltaic modules. Findings from literature and the case study were further supplemented with the insights from six experts. These experts had diverse backgrounds in research, manufacturing, and procurement to offer a variety of insights and perspectives on life extension strategies for photovoltaics. Finally, two scenarios were created for possible life extension pathways for used photovoltaic modules to illustrate the potential impacts compared to a commonplace premature replacement scenario. Economics and module performance are key factors in decision-making and acquisition of a photovoltaic ...

FAERE Working Paper, 2019.23 ; While environmental values are spreading among societies, theyhardly lead to effective political actions. This may be due to an overestimation of the sharing of those values among people, or to a lack ofpolitical power of environmentalists vis-à-vis materialist citizens. Wepropose a theoretical model to investigate these two channels, based ona setup a la Grossman and Helpman (1994), in which lobby is a strategy available to social groups, in order to influence the government onenvironmental taxes. Because societies have being historically markedby materialist habits, citizens sharing those habits face lower costswhen getting organized. By considering endogenous lobby formation ala Mitra (1999), we show that, in order for environmental and materialist lobbies to coexist, the society must be mixed enough. Based on adynamic framework a la Besley and Persson (2019), we investigate howsocial values change over time. Whenever lobbying by materialists prevails, a unique social equilibrium exists, featuring a stable hegemonyby materialist values. If environmentalists get organized too, a secondsocial equilibrium emerges, that is locally stable and more favorableto them. However, the threshold might be very high, above which thecultural transition effectively takes off. By calibrating the model, westudy counter-acting forces allowing to improve the odds of the environmental transition, such as cultural mutations, social-signaling, andlowering organizational costs. Finally, we provide policy implications. ; Alors que les valeurs environnementales se répandent dans les sociétés, elles ne débouchent guère sur des actions politiques efficaces. Cela peut être dû à une surestimation du partage de ces valeurs entre les gens, ou à un manque de pouvoir politique des écologistes vis-à-vis des citoyens matérialistes. Nous proposons un modèle théorique pour investiguer ces deux canaux, basé sur un cadre à la Grossman et Helpman (1994), dans lequel le lobbying est une stratégie à la disposition des ...

This deliverable includes the methodology in EnergyPROSPECTS for an in-depth study of energy citizenship. It features the criteria used for selecting the cases for indepth study, the list of cases selected for in-depth study as well as key research foci and empirical research questions.

The rapidly changing climate presents unprecedented challenges, especially in permafrost regions, where its thawing directly affects houses, mines, roads, pipelines, airport runways, and rail tracks. Monitoring the dynamics of ground ice in permafrost landscapes is essential for assessing geohazards and adapting infrastructure to changing conditions. This abstract presents a new initiative utilizing cosmic neutrons metrology for permafrost studies, specifically focusing on ground-ice content monitoring. Traditional methods for assessing ground-ice content in permafrost regions involve labor-intensive surveys and analysis of geomorphological features. However, these approaches are often limited in spatial coverage and may not capture the full extent of ground-ice distribution. In response to these challenges, we propose leveraging cosmic neutrons as a non-invasive and scalable method for assessing ground-ice content. Cosmic neutrons naturally penetrate the Earth's surface and interact with hydrogen atoms in the soil, including those bound in water molecules. By measuring the cosmic neutron albedo, which is the flux of epithermal neutrons that are partially thermalized in the ground, we can infer the presence and distribution of ground ice. This approach builds upon established techniques used for soil moisture monitoring, adapting them for permafrost studies. In that regard, we conducted Monte Carlo simulations of cosmic neutron transport and interaction with modeled ground to investigate the feasibility of using cosmic neutrons for ground-ice content monitoring. Our simulations considered various ground compositions and ice concentrations to assess the sensitivity of cosmic neutron measurements to ground-ice content. The results of our simulations provide promising proof-of-concept for the proposed method, demonstrating its potential for accurately estimating ground-ice content in permafrost landscapes. Additionally, we are developing at DOSEO (CEA – Saclay, France) thermal over fast neutron reference fields that could be used to test, characterize, and calibrate detectors specifically for the presented application. The proposed method offers several advantages. Firstly, it provides measurements on a metric scale (~10m wide on ~1m depth), effectively balancing local detail with regional coverage, thus making it well-suited for mapping geohazards on a kilometric scale. Additionally, cosmic neutrons albedo measurements is non-destructive and non-invasive and can be applied across diverse permafrost landscapes, offering valuable insights into ground-ice dynamics. Moreover, mapping ground-ice content is feasible through the flexible deployment of neutron detectors. These detectors can either be moved around the study area to gather spatially distributed measurements or installed as fixed monitoring stations, enabling continuous observation of ground-ice dynamics across different seasons and over time. Integration of data from cosmic neutrons albedo measurements into Geographic Information System (GIS) applications enhances the ability to map geohazards and predict future changes in permafrost landscape stability. By combining information on ground-ice content with elevation, drainage patterns, periglacial features, and infrastructure, a better understanding of the interactions between climate change and geohazards in permafrost regions is achievable.In conclusion, cosmic neutrons metrology offers a promising approach for monitoring ground-ice content in permafrost landscapes. By advancing our understanding of permafrost dynamics, this initiative contributes to the broader goals of cryosphere monitoring and sustainable development.

International audience Solar resource and forecasting in very short spatial and timescales (0–100 m, 0–30 min) is a challenging task that cannot be accurately achieved by satellite products or numerical weather predictions due to technical and methodological restrictions. For this reason, sky images from ground-based cameras are widely used during the last decade to deal with the high spatial and temporal variability of clouds and provide the needed inputs for numerical models for the current and forecasted (in short-term) solar irradiance. In this chapter, the available types of all-sky cameras/imagers are shortly presented. The chapter is focused on the state-of-the-art methodologies used to derive parameters needed for the estimations of solar resource and forecasting by a calibrated all-sky camera: cloud coverage, type, height, and velocity as well as aerosol optical properties. The application of these methodologies at Plataforma Solar de Almeria, in the frame of project: “Direct Normal Irradiance Nowcasting methods for optimized operation of concentrating solar technologies” (DNICast, http://www.dnicast-project.net/) is discussed. Finally, the chapter finishes with some propositions for future work in the recent, but quickly, developed research area.

Исследование ландшафтов всегда было традиционным научным направлением географии. В России подобная направленность исследований остаётся актуальной, несмотря на то, что термины «геоэкология» и «ландшафтная экология» сегодня более распространены в англоязычном научном сообществе. Наш краткий обзор показывает значительное ускорение антропогенных ландшафтных изменений в Европе, Центральной Азии и азиатской части России за последние пять десятилетий. Ландшафтные исследования в антропоцене должны быть направлены на достижение и сохранение устойчивости ландшафта при его высокой производительности, что включает в себя прекращение деградации ландшафтов, развитие культурных и сохранение природных ландшафтов. Чистая вода и чистый воздух, плодородные и здоровые почвы для производства продуктов питания и других экосистемных услуг, а также биологически разнообразная зеленая среда являются атрибутами ландшафтов, обеспечивающих выживание и благополучие населения. Дисциплинарные и междисциплинарные исследования должны генерировать знания, инновации и правила принятия действенных решений. Генерация знаний в глобализованном мире основана на сборе больших массивов данных и моделировании сценариев. Международные длительные полевые опыты и системы агроэкологического мониторинга будут предоставлять данные для экосистемных моделей и систем поддержки принимаемых решений. Landscape research has been a traditional scientific discipline of geography. This is still the case in Russia, whilst the terms geo-ecology and landscape ecology have become established in the English speaking scientific community. Our short review reveals huge and accelerating anthropogenic landscape transformations in Europe, Central Asia and Asian Russia since the end the 1960s. Landscape research in the Anthropocene has to focus on achieving landscape sustainability at high productivity. This includes halting landscape degradation, developing cultural landscapes, and maintaining semi-natural landscapes. Clean water and air, fertile and healthy soils for food and other ecosystem services and a green and bio-diverse environment are attributes of landscapes for the survival and well-being of humans. Research has to generate knowledge, innovations and decision rules by disciplinary, interdisciplinary and trans-disciplinary work. Knowledge generation in a globalized world is based on big data gathering and scenario modelling. International long-term experiments and agri-environmental monitoring systems will deliver data for ecosystem models and decision support systems.

The level of advancement in the understanding of the mechanical properties of volcanic rocks is comparatively lower than that of sedimentary rocks. As part of the SUCCEED Project (Synergetic Utilisation of CO2 Storage Coupled with Geothermal Energy Deployment), which aims to investigate the feasibility of injecting captured and produced CO2 into the reservoirs to enhance geothermal production and achieve permanent CO2 storage at the Hellisheiði Geothermal Field in Iceland, this experimental research provides significant insights into the petrophysical and mechanical properties of the volcanic rocks collected from surface outcrops. The subsurface in Hellisheiði is mainly built up of hyaloclastite formations and interglacial basaltic lavas. During a field campaign samples were collected in different outcrops, ensuring that the samples were of high quality and sufficiently diverse to enable comprehensive analysis. Four samples per block and rock type have been prepared from the collected blocks, and they have been subjected to different laboratory tests to evaluate their petrophysical properties, such as porosity, density, and permeability, and their geomechanical behavior, using Unconfined Compression Test (UCS), Active-Source Acoustic Test, and Splitting Tensile Strength Test. Additionally, laboratory experiments have been conducted to investigate the impact of rapid cooling on rock damage due to thermal fracturing. The results show that there are interdependent relationships between porosity, bulk density, ultimate strength, Young's modulus, and wave velocities that can be observed when considering average values per rock. The rocks studied showed a negative correlation between porosity and other parameters and a direct correlation between ultimate strength and Young's Modulus. When examining individual rock samples, no significant correlations were observed between porosity and other parameters, however, those correlations where evident when comparing between different rock types, emphasizing the importance of ...