FUTURE-FLOOD: New estimates of evolving UK flood risk for improved climate resilience

未来洪水：对英国不断变化的洪水风险的新估计，以提高气候适应能力

基本信息

批准号：
NE/X014134/1
负责人：
Elizabeth Kendon
金额：
$ 103.71万
依托单位：
University of Bristol
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2023
资助国家：
英国
起止时间：
2023 至无数据
项目状态：
未结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FX014134%2F1
关键词：
FUTURE FLOOD New estimates evolving

项目摘要

Recent devastating floods across the UK and Europe have highlighted the need to make society more resilient to flooding. This need is even more urgent given that flooding is predicted to become more frequent and destructive with climate change. However, current estimates of future flood risk in the UK and elsewhere are unreliable as they are typically based on coarse resolution climate models, which are unable to capture the short-duration rainfall extremes responsible for flooding. They also do not capture critical changes in the spatial extent and temporal clustering of rainfall events and neglect key physical processes in changing rainfall and river flow patterns. FUTURE-FLOOD is an ambitious project to advance our understanding of future inland flood risk and provide new flood estimates across the UK that are fit for purpose. It will bring together internationally state-of-the-art high resolution climate projections with advanced flood modelling capability. We will exploit a new set of continuous 100yr climate projections that provide rainfall data hour by hour, for every 2.2km grid box across the UK, for 1981-2080 for twelve ensemble members. This is like starting twelve weather forecasts and running each for 100yrs. These projections (an extension of "UKCP Local" only available for three 20yr periods) are unique in their spatial and temporal coverage. They will be exploited to gain new understanding of changes in rainfall over the coming years and decades, including changes in temporal clustering, antecedent conditions and spatial extent of events. Such changes are not well understood but are likely to be critically important for flood risk.The 100yr UKCP Local projections will be used to drive hydrological and flood models, providing a complete UK-wide assessment of changes in the frequency and severity of compound pluvial and fluvial flooding for the first time. UKCP Local rainfall data will be used directly such that complex changes to rainfall patterns and intensity distributions are captured in the simulated river flows and flood levels. A recent pilot study (carried out by the project team) showed that using the full UKCP Local space-time varying precipitation fields to drive flood models can lead to radically different estimates of future flood risks to those contained in current guidance based on simplified uplift methods. This pilot study did not capture compound effects and was limited to only one pluvial site (Bristol) and two fluvial catchments (Thet and Dyfi) but demonstrated the need for the national-scale study proposed here. We will compare results with flooding simulated using standard approaches and coarser resolution climate model data, assessing the reliability of existing flood predictions. Additional flood modelling experiments will allow us to identify the physical controls on flooding and its change through time, including the role of changes in the space-time variability of rainfall and its interactions with the landscape. This understanding will be key to identifying improved uplift approaches commonly used by practitioners for future flood risk assessment.Providing flood projections continuously over 100yrs is a major step forward and will enable us to interpret individual observed flood events in the context of climate change and translate results to changes for specific policy-relevant global warming levels. We will combine the new flood hazard information with estimates of exposure and vulnerability to estimate flood risk (e.g. properties flooded, damage to critical infrastructure, monetary loss). This estimation will include projections of socio-economic change. We will demonstrate the use of this new information in decision-making at national scale. We will also co-develop a local-scale demonstrator (initially for Bristol) with city decision-makers to take the new flood information through to improving city resilience, assessing the scope for and benefits of adaptive action.

英国和欧洲最近发生的毁灭性洪水强调了使社会对洪水更具韧性的必要性。鉴于预计洪水会随着气候变化的变化而变得更加频繁和破坏性，这种需求更加紧迫。但是，目前对英国和其他地方未来洪水风险的估计是不可靠的，因为它们通常基于粗分辨率的气候模型，这些气候模型无法捕获造成洪水的短期降雨极端。他们还没有在降雨和河流流动方式中忽略降雨事件的空间范围和时间聚类的关键变化，并忽略了关键的物理过程。 Future-Food是一个雄心勃勃的项目，旨在促进我们对未来内部洪水风险的理解，并在英国提供适合目的的新洪水估算。它将汇集国际上最先进的高分辨率气候预测，并具有先进的洪水建模能力。我们将利用一组新的100年气候预测，该预测每小时每小时提供降雨数据，每2.2公里的网格盒，1981 - 2080年为十二个合奏成员提供1981 - 2080年。这就像开始十二个天气预报并每次运行100年。这些预测（“ UKCP本地”的扩展仅在三个20年中可用）是独一无二的，它们的空间和时间覆盖范围是独一无二的。他们将被利用以获得对未来几年和几十年来降雨变化的新理解，包括时间聚类的变化，先行条件和事件的空间范围。这种变化尚未充分理解，但对于洪水风险至关重要。100岁的UKCP本地预测将用于推动水文和洪水模型，从而完全评估了第一次对复合pluvial和河流洪水的频率和严重性变化的评估。 UKCP局部降雨数据将直接使用，以使降雨模式的复杂变化和强度分布在模拟的河流和洪水水平中被捕获。最近的一项试点研究（由项目团队进行）表明，使用完整的UKCP当地时空变化的降水场来推动洪水模型，可能会导致基于简化的上升方法，对当前指南中包含的洪水风险的估计截然不同。这项试点研究没有捕获复合效应，仅限于一个Pluvial部位（Bristol）和两个河流集水区（Thet和Dyfi），但证明了这里提出的国家规模研究的需求。我们将将结果与使用标准方法模拟的洪水进行比较，并评估现有洪水预测的可靠性。其他洪水建模实验将使我们能够确定洪水及其随着时间的变化的物理控制，包括降雨时空变化的变化及其与景观的相互作用的作用。这种理解将是确定从业人员对未来洪水风险评估通常使用的改进的隆起方法的关键。对洪水预测不断超过100年是向前迈出的重要一步，这将使我们能够在气候变化的背景下解释个人观察到的洪水事件，并将结果转化为特定政策与特定政策相关的全球温暖水平的变化。我们将将新的洪水危害信息与估计暴露和估计洪水风险的脆弱性相结合（例如，财产淹没，对关键基础设施的损害，货币损失）。该估计将包括社会经济变革的预测。我们将在国家规模上证明在决策中使用这些新信息。我们还将与城市决策者共同开发地方规模的示威者（最初是布里斯托尔），以将新的洪水信息带入改善城市的弹性，评估适应性行动的范围和好处。