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Title: Multivariate statistical modelling of the drivers of compound flood events in south Florida
Abstract. Miami-Dade County (south-east Florida) is among the most vulnerable regions to sea level rise in the United States, due to a variety of natural andhuman factors. The co-occurrence of multiple, often statistically dependent flooding drivers – termed compound events – typically exacerbatesimpacts compared with their isolated occurrence. Ignoring dependencies between the drivers will potentially lead to underestimation of flood riskand under-design of flood defence structures. In Miami-Dade County water control structures were designed assuming full dependence between rainfalland Ocean-side Water Level (O-sWL), a conservative assumption inducing large safety factors. Here, an analysis of the dependence between theprincipal flooding drivers over a range of lags at three locations across the county is carried out. A two-dimensional analysis of rainfall andO-sWL showed that the magnitude of the conservative assumption in the original design is highly sensitive to the regional sea level rise projectionconsidered. Finally, the vine copula and Heffernan and Tawn (2004) models are shown to outperform five standard higher-dimensional copulas incapturing the dependence between the principal drivers of compound flooding: rainfall, O-sWL, and groundwater level. The work represents a firststep towards the development of a new framework capable of capturing dependencies between different flood drivers that could potentially beincorporated into future Flood Protection Level of Service (FPLOS) assessments for coastal water control structures.  more » « less
Award ID(s):
1929382
NSF-PAR ID:
10225391
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Natural Hazards and Earth System Sciences
Volume:
20
Issue:
10
ISSN:
1684-9981
Page Range / eLocation ID:
2681 to 2699
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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