Coastal Hazards: Multi-hazard controls on Flooding and Erosion (CHAMFER)

沿海灾害对全球和英国的人员、财产和基础设施构成重大风险。例如，仅在英格兰就有超过180万户家庭面临沿海洪水和侵蚀的风险，沿海洪水被认为是2020年国家风险登记册中影响最大的两大环境危害之一。预计沿海洪水和侵蚀的发生率、强度和影响将随着气候变化而增加，并将产生重大的社会经济后果。从历史上看，海岸保护一直依赖于大量使用硬工程防御计划，但这些计划的不利影响和高昂成本推动了基于自然过程工作（WWNP）的海岸实践的倡导。然而，未来的变化，区域海平面，风暴，洪积和河流的输入，沿海生境，以及它们之间的相互关系，导致显着的认识不确定性（由于知识有限）控制洪水和侵蚀，并限制实施WWNP计划。关于极端水动力条件的多种陆地和海洋驱动因素如何联合收割机在未来控制沿海洪水和侵蚀，关于沿海生境提供的保护服务的脆弱性和效力，以及WWNP解决方案在已经受到传统工程海岸防御部分保护的海岸上的性能。尺度海岸洪水和侵蚀主要是天气尺度气象事件的响应。这些气象事件可能对沿海环境造成一系列单独的危害，如风暴潮、极端海浪、极端降雨和极端河流流量。然而，这些危险成分并不是相互独立的，海岸洪水和侵蚀通常是由于相互关联和/或连续的危险成分的集体影响而引起的。换句话说，海岸洪水和侵蚀是由多种灾害控制的。CHAMFER项目将研究海岸的多种灾害如何控制海岸洪水和侵蚀，并确定这些多种灾害如何应对气候变化和海岸管理。我们将提供一个新的社区建模系统，该系统连接陆地和海洋部门，其数值模拟将用于支持当前和未来情景下的多种灾害分析。这将与对沿海生境作用的评估相结合，从而产生关于沿海生境的保护服务和易受气候驱动的多种灾害影响的脆弱性的国家地图。我们将提供工具来分析未来WWNP计划的有效性。CHAMFER将在空间和时间两方面采用多尺度方法，前者考虑英国/英国尺度和更多的地方空间尺度，后者考虑在长期气候相关或管理相关变化下对气象事件的反应。CHAMFER包括与利益相关者共同设计的重要元素，我们将与政府部门，公共部门组织和行业用户合作，为沿海保护和适应方案提供信息和支持。

Coastal hazards pose a significant risk to people, property, and infrastructure worldwide and in the UK. For example, over 1.8 million homes are at risk of coastal flooding and erosion in England alone and coastal flooding is recognized as one of the top two environmental hazards in terms of impact in the 2020 National Risk Register. The occurrence, intensity and impacts of coastal flooding and erosion are projected to increase with climate change and will have major socio-economic consequences. Historically, coastal protection has relied on overwhelming use of hard engineered defence schemes, but adverse effects and high costs of these schemes have driven advocacy of coastal practices that are based on Working with Natural Processes (WWNP). However, future changes in regional sea level, storms, pluvial and fluvial inputs, coastal habitats, and their interrelations lead to significant epistemic uncertainties (due to limited knowledge) about controls on flooding and erosion and limit the implementation of WWNP schemes. Questions remain on how multiple terrestrial and marine drivers of extreme hydrodynamic conditions will combine to control coastal flooding and erosion in the future, on the vulnerability and efficacy of protective services afforded by coastal habitats, and on the performance of WWNP solutions on coasts that already have partial protection by traditional engineered coastal defences.Event-scale coastal flooding and erosion mainly occur in response to synoptic scale meteorological events. These meteorological events can result in a series of individual hazard components to coastal environments, such as storm surges, extreme waves, extreme rainfall, and extreme river flows. However, these hazard components are not independent of each other, and coastal flooding and erosion commonly arise from the collective impact due to interrelated and/or successive hazard components. In other words, coastal flooding and erosion are controlled by multi-hazards.The CHAMFER project will characterise how multi-hazards at the coast control coastal flooding and erosion and determine how these multi-hazards will respond to climate change and coastal management. We will deliver a new community modelling system coupled across terrestrial and marine sectors, numerical simulations of which will be used to support multi-hazard analyses under present and future scenarios. This will be combined with an assessment of the role of coastal habitats resulting in national maps for protective services and vulnerabilities of coastal habitats to climate-driven multi-hazards. We will provide tools to analyse the efficacy of future WWNP schemes. CHAMFER will rely on a multi-scale approach both spatially, by considering UK/GB scales and more local spatial scales, and temporally, by considering responses to meteorological events under long-term climate-related or management-related changes. CHAMFER includes significant elements of co-design with stakeholders and we will work with government departments, public sector organisations, and industry users to inform and support coastal protection and adaptation options.