摘要：The changing climate and anthropogenic activities raise thelikelihood of damage due to compound flood hazards, triggered by thecombined occurrence of extreme precipitation and storm surge during hightides and exacerbated by sea-level rise (SLR). Risk estimates associatedwith these extreme event scenarios are expected to be significantly higherthan estimates derived from a standard evaluation of individual hazards. Inthis study, we present case studies of compound flood hazards affectingcritical infrastructure (CI) in coastal Connecticut (USA). We based theanalysis on actual and synthetic (considering future climate conditions foratmospheric forcing, sea-level rise, and forecasted hurricane tracks)hurricane events, represented by heavy precipitation and surge combined withtides and SLR conditions. We used the Hydrologic Engineering Center's RiverAnalysis System (HEC-RAS), a two-dimensional hydrodynamic model, to simulatethe combined coastal and riverine flooding of selected CI sites. We forced adistributed hydrological model (CREST-SVAS) with weather analysis data fromthe Weather Research and Forecasting (WRF) model for the synthetic eventsand from the National Land Data Assimilation System (NLDAS) for the actualevents, to derive the upstream boundary condition (flood wave) of HEC-RAS.We extracted coastal tide and surge time series for each event from theNational Oceanic and Atmospheric Administration (NOAA) to use as thedownstream boundary condition of HEC-RAS. The significant outcome of thisstudy represents the evaluation of changes in flood risk for the CI sitesfor the various compound scenarios (under current and future climateconditions). This approach offers an estimate of the potential impact ofcompound hazards relative to the 100-year flood maps produced by the FederalEmergency Management Agency (FEMA), which is vital to developing mitigationstrategies. In a broader sense, this study provides a framework forassessing the risk factors of our modern infrastructure located invulnerable coastal areas throughout the world.
