Medidas de adaptação para aumentar a segurança hídrica em bacias sob mudança

Climate change and extreme events significantly impact water security in basins worldwide. The increasing frequency and intensity of extreme weather events such as floods and droughts threaten the sustainability of water resources, jeopardizing economic development and social welfare. Therefore, it underlines the importance of adaptation strategies to enhance water security and build resilience in the face of climate change. This thesis aims to put forward risk pooling and index-based insurance as viable adaptation measures to enhance water security and bolster the resilience of catchments experiencing environmental changes in Brazil. We begin with a review of water security in Brazil, analyzing the peculiarities of each geographic region and hydrographic area. This analysis highlights the following challenges and opportunities for water management in Brazil: (1) the need to consider climate change scenarios in current and future policies, (2) improve and invest in non-structural adaptation measures, (3) involve society in the development of these mitigation and adaptation measures, and (4) improve cooperation between researchers and decision-makers. Given these challenges, we proposed the first adaptation measure: risk pooling. In order to do so, we present a novel framework to identify the spatial connectivity of hydrological droughts and propose the risk-pooling regions based on catchment connectivity characteristics. We have identified five regions within the country exhibiting similar drought patterns. These regions serve as a basis for devising risk-pooling strategies. In such strategies, regions located outside the identified drought similarity regions can form risk pooling regions to mitigate the impact of widespread droughts. A case study was applied to propose the second adaptation measure, index-based insurance. The study simulates multi-year and multi-risk index-based insurance for a Water Supply System, considering the impacts of climate change on water availability and demand. Based on the findings of the study case, we can provide suggestions for a contract structure that may be valuable to Brazilian water supply companies. We could assume that water utilities and consumers can regulate and reduce the financial effect of drought and flood disasters by adopting index-based insurance. Overall, we can conclude that the implementation of risk pooling mechanisms and index-based insurance as adaptive strategies in Brazil\'s catchments would improve water security and resilience by reducing the impact of extreme events, managing water shortages, guiding adaptation plans, and mitigating economic losses. This thesis provides a valuable contribution to the understanding of water resource planning and management, providing insights for effective water governance, sustainable development, and improved water security in Brazil.As mudanças climáticas e os eventos extremos impactam significativamente a segurança hídrica em bacias hidrográficas em todo o mundo. A crescente frequência e intensidade de eventos climáticos extremos, como enchentes e secas, ameaçam a sustentabilidade dos recursos hídricos, comprometendo o desenvolvimento econômico e o bem-estar social. Portanto, enfatiza a necessidade de medidas de adaptação para segurança hídrica e construir resiliência diante das mudanças climáticas. Esta tese tem como objetivo apresentar o agrupamento (\"pool\") de riscos e o seguro baseado em índices como medidas de adaptação viáveis para aumentar a segurança hídrica e reforçar a resiliência de bacias que sofrem mudanças ambientais no Brasil. Iniciamos com uma revisão da segurança hídrica no Brasil, analisando as peculiaridades de cada região geográfica e área hidrográfica. Esta análise destaca os seguintes desafios e oportunidades para a gestão da água no Brasil: (1) a necessidade de considerar cenários de mudanças climáticas nas políticas atuais e futuras, (2) aprimorar e investir em medidas não estruturais de adaptação, (3) envolver a sociedade na desenvolvimento dessas medidas de mitigação e adaptação, e (4) melhorar a cooperação entre pesquisadores e tomadores de decisão. Diante desses desafios, propusemos a primeira medida de adaptação: o agrupamento de risco. Para isso, apresentamos uma nova estrutura metodológica para identificar a conectividade espacial das secas hidrológicas e propusemos regiões de agrupamento de riscos com base nas características de conectividade da bacia. Identificamos cinco regiões dentro do país que exibem padrões de seca semelhantes. Essas regiões servem como base para a criação de grupos de risco. Em tais grupos, regiões localizadas fora das regiões de similaridade de seca identificadas podem formar regiões de risco para mitigar o impacto de secas generalizadas. Um estudo de caso foi aplicado para propor a segunda medida de adaptação, seguro baseado em índice. O estudo simula um seguro baseado em índices plurianuais e multirriscos para um Sistema de Abastecimento de Água, considerando os impactos das mudanças climáticas na disponibilidade e demanda de água. Com base nos resultados do estudo de caso, podemos fornecer sugestões para uma estrutura de contrato que pode ser valiosa para as empresas brasileiras de abastecimento de água. Poderíamos presumir que as concessionárias de água e os consumidores podem regular e reduzir o efeito financeiro de desastres de seca e inundação adotando um seguro baseado em índices. No geral, podemos concluir que a implementação de mecanismos de agrupamento de riscos e seguro baseado em índices como estratégias adaptativas nas bacias hidrográficas do Brasil melhorariam a segurança hídrica e a resiliência, reduzindo o impacto de eventos extremos, gerenciando a escassez de água, orientando os planos de adaptação e mitigando as perdas econômicas. Esta tese fornece uma contribuição valiosa para a compreensão do planejamento e gestão dos recursos hídricos, fornecendo insights para uma governança eficaz da água, desenvolvimento sustentável e maior segurança hídrica no Brasil

Assessing water security in the Sao Paulo metropolitan region under projected climate change

Climate change affects the global water cycle and has the potential to alter water availability for food–energy–water production, and for ecosystems services, on regional and local scales. An understanding of these effects is crucial for assessing future water availability, and for the development of sustainable management plans. Here, we investigate the influence of anticipated climate change on water security in the Jaguari Basin, which is the main source of freshwater for 9 million people in the São Paulo metropolitan region (SPMR). First, we calibrate and evaluate a hydrological model using daily observed data, obtaining satisfactory coefficient of determination and Kling–Gupta efficiency values for both periods. To represent possible climate change scenarios up to 2095, we consider two International Panel on Climate Change (IPCC) Representative Concentration Pathways (RCP4.5 and RCP8.5) and use an ensemble of future projections generated by 17 general circulation models (GCMs). These data were used to drive the hydrological model to generate projected scenarios of streamflow. We then used indicators of water scarcity and vulnerability to carry out a quantitative analysis of provision probability. Our results indicate that streamflow can be expected to exhibit increased interannual variability, significant increases in flow rate between January and March, and a 2-month extension of the hydrological dry season (currently June to September) until November. The latter includes a more than a 35 % reduction in streamflow during September through November (with a > 50 % reduction in October). Our findings indicate an increased risk of floods and droughts accompanied by an expansion of the basin critical period, and our analysis of the water security indices identifies October and November as the most vulnerable months. Overall, our analysis exposes the fragility of water security in the São Paulo metropolitan region, and provides valuable technical and scientific information that can be used to guide regional plans and strategies to cope with potential future water scarcity.Ministry of Science, Technology, Innovation and Communication, MCTIC; National Council for Scientific and Technological Development, CNPqNational Council for Scientific and Technological Development (CNPq) [441289/2017-7, 306830/2017-5]Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

CLIMBra - Climate Change Dataset for Brazil

Abstract General Circulation and Earth System Models are the most advanced tools for investigating climate responses to future scenarios of greenhouse gas emissions, playing the role of projecting the climate throughout the century. Nevertheless, climate projections are model-dependent and may show systematic biases, requiring a bias correction for any further application. Here, we provide a dataset based on an ensemble of 19 bias-corrected CMIP6 climate models projections for the Brazilian territory based on the SSP2-4.5 and SSP5-8.5 scenarios. We used the Quantile Delta Mapping approach to bias-correct daily time-series of precipitation, maximum and minimum temperature, solar net radiation, near-surface wind speed, and relative humidity. The bias-corrected dataset is available for both historical (1980–2013) and future (2015–2100) simulations at a 0.25° × 0.25° spatial resolution. Besides the gridded product, we provide area-averaged projections for 735 catchments included in the Catchments Attributes for Brazil (CABra) dataset. The dataset provides important variables commonly used in environmental and hydroclimatological studies, paving the way for the development of high-quality research on climate change impacts in Brazil

Where should hydrology go? An early-career perspective on the next IAHS Scientific Decade: 2023-2032

This paper shares an early-career perspective on potential themes for the upcoming International Association of Hydrological Sciences (IAHS) scientific decade (SD). This opinion paper synthesizes six discussion sessions in western Europe identifying three themes that all offer a different perspective on the hydrological threats the world faces and could serve to direct the broader hydrological community: “Tipping points and thresholds in hydrology”, “Intensification of the water cycle”, and “Water services under pressure”. Additionally, four trends were distinguished concerning the way in which hydrological research is conducted: big data, bridging science and practice, open science, and inter- and multidisciplinarity. These themes and trends will provide valuable input for future discussions on the theme for the next IAHS SD. We encourage other Early-Career Scientists to voice their opinion by organizing their own discussion sessions and commenting on this paper to make this initiative grow from a regional initiative to a global movement

Where should hydrology go? An early-career perspective on the next IAHS Scientific Decade: 2023–2032

This paper shares an early-career perspective on potential themes for the upcoming International Association of Hydrological Sciences (IAHS) Scientific Decade (SD). This opinion paper synthesizes six discussion sessions in western Europe identifying three themes that all offer a different perspective on the hydrological threats the world faces and could serve to direct the broader hydrological community: “Tipping points and thresholds in hydrology,” “Intensification of the water cycle,” and “Water services under pressure.” Additionally, four trends were distinguished concerning the way in which hydrological research is conducted: big data, bridging science and practice, open science, and inter- and multidisciplinarity. These themes and trends will provide valuable input for future discussions on the theme for the next IAHS SD. We encourage other early-career scientists to voice their opinion by organizing their own discussion sessions and commenting on this paper to make this initiative grow from a regional initiative to a global movement