气候变化领域集成服务门户(CCPortal): Toward a New Flood Assessment Paradigm: From Exceedance Probabilities to the Expected Maximum Floods and Damages

CCPortal

DOI	10.1029/2023WR034477
	Toward a New Flood Assessment Paradigm: From Exceedance Probabilities to the Expected Maximum Floods and Damages
	Todini, E.; Reggiani, P.
发表日期	2024
ISSN	0043-1397
EISSN	1944-7973
起始页码	60
结束页码	1
卷号	60 期号:1
英文摘要	To assess flood risks, we seek to estimate the probability distribution of the worst possible single-event over a contiguous period of N years rather than the cumulative losses expected over a planning horizon. For this we use the probability distribution FN of extreme flood events over a multi-year period, which is different from using the conventional single-valued exceedance probability of 1/N years. FN can be used to estimate the hazard and then proceed to the estimation of risk, which we define as the largest expected damage over the set period. It also allows for a more coherent determination of design values, which descend from fully acknowledging the aleatoric uncertainty of the underlying natural river flow process. The epistemic uncertainty is removed by marginalizing the aleatoric-epistemic uncertainty joint distribution over the parameter space. The advantage of the proposed Bayesian approach, which can be summarized in 12 steps, is demonstrated for the 2021 River Ahr flood in Germany, which caused casualties and huge material damage. Adopting the multi-year maxima extreme value distribution can potentially lead to the reclassification of vulnerability levels for flood-prone areas and reconsideration of current policy-making and flood risk communication. To assess risks from extreme flood events, we seek to estimate the probability distribution of the worst possible single-event over a contiguous period of for example, N = 100 or more year years and the cumulative losses expected over the planning horizon for a hydraulic protection measure. For this we use the probability distribution of extreme flood events over a multi-year period, which is different from using the conventional single-valued exceedance probability of 1/N years. This distribution can be used to estimate the largest expected damage over the entire planning horizon. It also allows for a more coherent determination of design values, which we obtain from fully acknowledging the climatological (and not epistemic) uncertainty of extreme flow events. The advantage of the proposed approach is demonstrated for the 2021 River Ahr flood in Germany, which caused casualties and huge material damage. Using the multi-year maxima extreme value distribution instead of return periods should lead to a more consistent classification of vulnerability levels for flood-prone areas and to reconsideration of current policy-making and flood risk communication. Approach examines probability distribution of largest flood during a multi-year planning horizonYields different estimates of maximum flood in a multi-year period than exceedance probabilitiesBayesian inference enables consideration of both aleatory and epistemic uncertaintiesExpected maximum damages can be computed using expected maximum floodNew assessment approach demonstrated through case study in Germany
英文关键词	flood risk; aleatoric uncertainty; epistemic uncertainty; multi-year maxima distribution; extreme events distribution; expected damage estimation
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Marine & Freshwater Biology ; Water Resources
WOS类目	Environmental Sciences ; Limnology ; Water Resources
WOS记录号	WOS:001142186600001
来源期刊	WATER RESOURCES RESEARCH
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/306554
作者单位	Universitat Siegen
推荐引用方式 GB/T 7714	Todini, E.,Reggiani, P.. Toward a New Flood Assessment Paradigm: From Exceedance Probabilities to the Expected Maximum Floods and Damages[J],2024,60(1).
APA	Todini, E.,&Reggiani, P..(2024).Toward a New Flood Assessment Paradigm: From Exceedance Probabilities to the Expected Maximum Floods and Damages.WATER RESOURCES RESEARCH,60(1).
MLA	Todini, E.,et al."Toward a New Flood Assessment Paradigm: From Exceedance Probabilities to the Expected Maximum Floods and Damages".WATER RESOURCES RESEARCH 60.1(2024).