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Floods are among the most frequent and damaging hazards worldwide, with impacts intensified by climate change and rapid urban growth. This review analyzes how satellite-based Earth Observation (EO) technologies are evolving to meet operational needs in flood detection and water depth estimation, with a focus on the Copernicus Emergency Management Service (CEMS) as a mature and widely adopted European framework. We compare the capabilities of conventional EO datasets—optical and Synthetic Aperture Radar (SAR)—with 3D geospatial datasets such as high-resolution Digital Elevation Models (DEMs) and Light Detection and Ranging (LiDAR). While 2D EO imagery is essential for rapid surface water mapping, 3D datasets add volumetric context, enabling improved flood depth estimation and urban impact assessment. LiDAR, in particular, can capture microtopography between high-rise structures, but its operational use is constrained by cost, data availability, and update frequency. We also review how artificial intelligence (AI), including machine learning and deep learning, is enhancing automation, generalization, and near-real-time processing in flood mapping. Persistent gaps remain in model transferability, uncertainty quantification, and the integration of scarce high-resolution topographic data. We conclude by outlining a roadmap towards hybrid frameworks that combine EO observations, 3D datasets, and physics-informed AI, bridging the gap between current technological capabilities and the demands of real-world emergency management.

Digital Twin (DT) technology has emerged as a transformative tool in urban flood risk management (UFRM), enabling real-time data integration, predictive modeling, and decision support. This systematic review synthesizes existing literature to evaluate the scientific impact, technological advancements, and practical applications of DTs in UFRM. Using the PRISMA 2020 framework, we retrieved 1085 records (Scopus = 85; Web of Science = 1000), merged and deduplicated them using DOI and fuzzy-matched titles, screened titles/abstracts, and assessed full texts. This process yielded 85 unique peer-reviewed studies published between 2018 and 2025. Key findings highlight the role of remote sensing (e.g., satellite imagery, IoT sensors) in enhancing DT accuracy, the integration of machine learning for predictive analytics, and case studies demonstrating reduced flood response times by up to 40%. Challenges such as data interoperability and computational demands are discussed, alongside future directions for scalable, AI-driven DT frameworks. This review identifies key technical and governance challenges while recommending the development of modular, AI-driven DT frameworks, particularly tailored for resource-constrained regions.

Abstract Objective This study examines the scope and trends of empirical research on training activities for flood disaster response teams. Methods A scoping review, adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines, was conducted in June 2024 across four electronic databases and grey literature. The analysis included experimental and quasi-experimental studies published since 2005. An initial pool of 1193 studies was identified, 18 met the eligibility criteria and were included in the final analysis. Results These studies revealed three key themes: 1) evaluation and improvement of operational procedures, 2) preparation of response teams, and 3) management of health-related issues. Conclusion The results highlight the limited availability of empirical evidence in this area, reflecting the relatively small number of studies focusing specifically on training activities for flood disaster response teams. However, research in this field has shown growth since 2010, with a notable integration of educational technologies in most studies. Key training topics include psychological first aid and the evaluation of operational plans. Given the increasing frequency and severity of flood disasters due to global warming, further research is essential to develop and implement effective training programs, enabling response teams to address such emergencies more efficiently and comprehensively.

Urban areas face escalating hydrological risks due to climate change, urban sprawl, and aging stormwater infrastructures. In this context, Nature-Based Solutions (NbSs), especially Sustainable Urban Drainage Systems (SUDSs), have emerged as viable strategies to enhance water resilience and sustainability. However, the literature still lacks standardized and scalable methodologies for their design and performance monitoring. This study conducts a systematic review following the PRISMA protocol, combined with bibliometric and co-occurrence analyses, to identify prevailing approaches in the sizing and monitoring of NbS-based SUDSs. Based on the peer-reviewed literature indexed in Scopus and Web of Science from 2020 to 2024, the findings reveal an increasing integration of hydrological modeling with artificial intelligence, remote sensing, and IoT-based real-time monitoring. Despite this progress, challenges remain in methodology validation, data availability, and system adaptability. The review underscores the need for hybrid, context-sensitive frameworks that integrate empirical and simulated data to support decision-making in urban drainage planning and management.

ABSTRACT Despite increasing scholarly attention to flood risk management (FRM), there remains limited systematic understanding of how network governance arrangements influence FRM outcomes. This knowledge gap is particularly critical given the frequency and severity of floods, causing significant socio‐economic and environmental damages globally. Through a systematic literature review analyzing 38 peer‐reviewed publications from 2000 to 2023, this paper investigates network governance in FRM using a three‐component analytical framework examining actor constellations, operational activities, and governance outcomes. Our analysis explores the nature of network actor constellations in FRM research, the exchanges characterizing their operational activities, and the resultant governance outcomes that emerge from their interactions. The findings identify distinct network configurations: formal state agencies at different governance scales, informal local networks and bottom‐up initiatives, and hybrid constellations incorporating both state and non‐state actors. Operational activities are shaped by complex interdependencies including altruistic support, resource exchanges, knowledge flows, power dynamics, formal collaborations, and trust‐based sociability. Our results reveal both desired outcomes, such as social learning and innovation, and undesired outcomes stemming from structural weaknesses and pragmatic constraints. For improving FRM practice and governance outcomes, we suggest, where possible, shifting more responsibility to highly effective non‐state actors, managing negative interdependencies, and leveraging network governance throughout FRM phases. Our findings provide practical guidance for policymakers and practitioners for optimizing FRM governance arrangements while contributing theoretically to understanding how different network types influence flood resilience outcomes across developed and developing contexts. This article is categorized under: Human Water > Water Governance

This review examines South Africa’s escalating flood vulnerability through a synthesis of over 80 peer-reviewed articles, historical records, policy reports, and case studies. Using a PRISMA-guided analysis, the study identifies key climatic drivers, including extreme rainfall from tropical–temperate interactions, cut-off lows, and La Niña conditions that interact with structural weaknesses such as inadequate drainage, poorly maintained stormwater systems, and rapid urban expansion. Apartheid-era spatial planning has further entrenched risk by locating marginalised communities in floodplains. Governance failures like weak disaster risk reduction (DRR) policies, fragmented institutional coordination, and insufficient early warning systems intensify flood vulnerabilities. Catastrophic events in KwaZulu-Natal (KZN) and the Western Cape (WC) illustrate the consequences exemplified by the April 2022 KZN floods alone, which caused over 450 deaths, displaced more than 40,000 people, and generated damages exceeding ZAR 17 billion. Nationally, more than 1500 flood-related fatalities have been documented in the past two decades. Emerging resilience pathways include ecosystem-based adaptation, green infrastructure, participatory governance, integration of Indigenous knowledge, improved hydrological forecasting, and stricter land-use enforcement. These approaches can simultaneously reduce physical risks and address entrenched socio-economic inequalities. However, significant gaps remain in spatial flood modelling, gender-sensitive responses, urban–rural disparities, and policy implementation. The review concludes that South Africa urgently requires integrated, multi-scalar strategies that combine scientific innovation, policy reform, and community-based action. Embedding these insights into disaster management policy and planning is essential to curb escalating losses and build long-term resilience in the face of climate change.

Abstract The Atlantic meridional overturning circulation (AMOC) plays a crucial role in regulating global and regional climate by distributing heat meridionally across the planet. Future projections indicate a weakening of the AMOC in response to increased greenhouse gas concentrations. In this study, we investigate the impact of AMOC weakening on South America's mean climate, as well as temperature and precipitation extremes. We analyze targeted sensitivity experiments using the EC‐Earth3 climate model. Our findings reveal that AMOC weakening induces cooling and wetting in the tropics of South America, contrasted by warming and dryness in the extratropics. This pattern weakens the meridional temperature gradient, shifts the intertropical convergence zone and the high‐latitude winter and summer jets southward, and reduces midlatitude storm tracks, particularly in austral winter. We analyze extreme events in two representative regions—La Plata Basin and northeast Brazil—which exhibit contrasting responses. In La Plata Basin, summer heat waves become more frequent, intense, and prolonged, while winter cold spells occur more frequently but with decreased intensity and duration when the AMOC reduces. In contrast, northeast Brazil experiences an increase in the frequency and intensity of heat waves, while cold spells become less frequent but more intense. Extreme precipitation events weaken in the La Plata Basin but intensify in northeast Brazil in both seasons under AMOC weakening. Some of these climate impacts may exacerbate global warming effects, while others may partially offset them. These findings underscore the critical need to refine climate models' representation of AMOC dynamics to improve predictions of future climate scenarios. , Plain Language Summary The Atlantic meridional overturning circulation (AMOC) helps to regulate the Earth's climate by transporting heat around the globe. Scientists expect it to weaken in the future due to global warming. This study looks at how a weaker AMOC could affect South America's climate, including temperature and rainfall extremes. Using a climate model, the researchers found that a weaker AMOC would make tropical South America cooler and wetter, while the extratropical regions would get warmer and drier. This change is associated with modifications in weather patterns like jet streams and storm tracks. They focused on two important regions: the La Plata Basin and northeast Brazil to analyze extreme events. In the La Plata Basin, summers would have more intense and longer‐lasting heat waves, while winters would have more frequent but milder cold spells. Northeast Brazil, on the other hand, would see stronger and more frequent heat waves, and less frequent but harsher cold spells. Rainfall extremes would decrease in the La Plata Basin but increase in northeast Brazil. Some of these changes could make global warming amplificated, while others might ease its effects a bit. The study highlights the importance of improving how climate models simulate AMOC to better predict future climate changes. , Key Points The Atlantic meridional overturning circulation is projected to weaken, and this affects the South America mean climate and extreme events A weaker AMOC would induce cooling and wetting in tropical South America, whereas warming and drying in the extratropics Some climate impacts of a weakened AMOC in South America may amplify the effects of global warming, while others could counteract them

L’étude des déterminants des représentations liées aux risques et leurs effets sur les niveaux de préparation des populations exposées conduit à des conclusions souvent contradictoires d’une étude de cas à une autre. De nombreuses théories et hypothèses concurrentes ont été formulées dans des disciplines différentes, mais aucune n’est parvenue à s’imposer empiriquement. La validation croisée des résultats est complexe et le champ des risk perception s’apparente souvent à une collection d’études de cas indépendantes et peu comparables. À partir d’une enquête par questionnaire sur les représentations liées au risque inondation à Paris et en Île-de-France sur un échantillon de grande taille (n=2976), cet article propose une réflexion théorique et méthodologique pour consolider le positionnement de la géographie dans le champ des représentations des risques, pour mieux démêler les facteurs sociaux et territoriaux. Les questions de recherche se structurent autour du rôle de l’exposition aux aléas, de l’expérience préalable, des situations de vulnérabilité et des territoires de résidence sur les représentations puis sur les comportements. L’hypothèse principale est que les résultats contradictoires publiés dans la littérature internationale pour cerner les déterminants de ces représentations découlent d’approches disciplinaires et de théories divergentes, ainsi que de la place parfois peu assurée de la géographie dans le champ international des risk perception. , The study of risk perception determinants and their impacts on the levels of preparedness of exposed populations often leads to inconclusive results across case studies. Numerous competing theories and hypotheses have been formulated across different disciplines, but their empirical validation remains a challenge. The current fragmentation of research on risk perception hampers the cross-validation of previous results, which might make the field appear as a collection of independent case studies in some instances. We use a flood risk perception and emergency behaviour survey in Paris, France(n=2976), to discuss a theoretical and methodological approach to consolidating the position of geography in the field, better disentangling social and spatial factors. The research questions are structured around the role of hazard exposure, prior experience, place of residence, and social vulnerability on risk perception and emergency behaviour. The main hypothesis is that previous inconclusive results published in the literature on risk perception determinants stem from divergent disciplinary approaches and theories, as well as from the at times uncertain place of geography in the field. , El estudio de las determinantes de la percepción del riesgo y sus efectos sobre los niveles de preparación de la población expuesta, entregan resultados contradictorios según el caso analizado. Si bien han sido propuestas una amplia gama de hipótesis y teorías, éstas restan contrapuestas entre disciplinas y ninguna ha podido prevalecer empíricamente. La validación cruzada de los resultados resulta compleja, y el campo de la percepción del riesgo se asocia generalmente a una colección de estudios de casos independientes y con una baja capacidad de hacerlos comparables. A partir de una encuesta realizada a 2976 personas referente a las representaciones del riesgo de inundación aplicada en la ciudad de París y en la región de Île-de-France, este artículo propone un enfoque teórico y metodológico en vías de consolidar la posición de la geografía en el campo de las representaciones del riesgo, con el fin de dilucidar de manera más robusta los factores sociales y territoriales. Las preguntas de investigación se estructuran en torno al rol de la exposición al peligro, la experiencia previa, las situaciones de vulnerabilidad, el lugar de residencia en las representaciones y los comportamientos. La hipótesis principal expresa que los resultados publicados en la literatura internacional para identificar las determinantes de estas representaciones son contradictorios, lo cuales derivan tanto de enfoques y teorías disciplinariamente divergentes, como del rol en ocasiones incierto que toma la geografía en el ámbito internacional de la percepción del riesgo.

The objective of this article is to analyze the impacts of climatic, physiographic, and land use/cover factors on the spatiotemporal variability of 7-day low-flow occurrence dates for 17 rivers during the period 1950–2023 in winter and summer in southern Quebec. Regarding spatial variability, correlation analysis revealed that these occurrence dates are primarily negatively correlated with agricultural surface area (early occurrence) during both seasons. In winter, they are also negatively correlated with total rainfall and daily mean maximum temperatures, but positively correlated with forest area and mean watershed slopes. Regarding temporal variability, the application of three Mann–Kendall tests showed that in summer, 7-day low flows tend to occur late in the season due to increased rainfall, particularly in the most agricultural watersheds. In contrast, in winter, very few significant changes were observed in the long-term trend of the analyzed hydrological series. Correlation analysis using redundancy analysis between eight climate indices and the occurrence dates of 7-day low flows showed that in summer, these dates are positively correlated with the global warming climate index, while they are not correlated with any climate index in winter. This study demonstrated that the spatiotemporal variability of the occurrence dates and magnitude of 7-day low flows are not influenced by the same factors in southern Quebec, except for the global warming climate index in summer. Finally, this study shows that the timing is much less sensitive to changes in climate change than the magnitude of low flows in southern Quebec.