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This paper presents a new methodology for selecting hazard-consistent hurricane scenarios (with similar return periods) for estimating the regional losses due to combined hurricane wind and flood. An in-house stochastic hurricane simulation program was used to simulate 50,000 years of full-track synthetic hurricanes. A wind field model along with a boundary layer model was utilized to compute the surface wind speeds. As illustrative examples, the SLOSH (Sea, Lake, and Overland Surges from Hurricanes) model was employed to calculate the corresponding flood elevations for two loss estimation domains (Charleston Peninsula, South Carolina and Miami Beach, Florida) with each of them divided into census blocks. The peak wind speeds and maximum flood elevations at the centroids of respective census blocks were utilized to determine the joint mean recurrence intervals (MRIs) of individual hurricane events. For regional loss estimation purpose, the joint MRIs of hurricanes were weighted by the population of every census block. A hurricane selection procedure was developed to select hazard-consistent hurricane scenarios with a joint MRI of 100 years. Three hurricane ensembles, selected based on only wind speeds, only flood elevations, and joint wind speeds and flood elevations, were imported into the HAZUS-MH (Hazards US Multi-Hazards) program to perform combined wind and flood loss estimations. The results indicate that hurricane selection using either only wind speeds or only flood elevations can overestimate the combined losses. The different characteristics of the selected hurricane scenarios for the two loss estimation domains are also discussed. [ABSTRACT FROM AUTHOR]

Combined effects of hurricane wind and surge can pose significant threats to coastal cities. Although current design codes consider the joint occurrence of wind and surge, information on site-specific joint distributions of hurricane wind and surge along the US Coast is still sparse and limited. In this study, joint hazard maps for combined hurricane wind and surge for Charleston, South Carolina (SC), were developed. A stochastic Markov chain hurricane simulation program was utilized to generate 50,000 years of full-track hurricane events. The surface wind speeds and surge heights from individual hurricanes were computed using the Georgiou's wind field model and the Sea, Lake and Overland Surges from Hurricanes (SLOSH) model, respectively. To validate the accuracy of the SLOSH model, the simulated surge levels were compared to the surge levels calculated by another state-of-the-art storm surge model, ADCIRC (Advanced Circulation), and the actual observed water elevations from historical hurricane events. Good agreements were found between the simulated and observed water elevations. The model surface wind speeds were also compared with the design wind speeds in ASCE 7-10 and were found to agree well with the design values. Using the peak wind speeds and maximum surge heights, the joint hazard surfaces and the joint hazard maps for Charleston, SC, were developed. As part of this study, an interactive computer program, which can be used to obtain the joint wind speed and surge height distributions for any location in terms of latitude and longitude in Charleston area, was created. These joint hazard surfaces and hazard maps can be used in a multi-hazard design or risk assessment framework to consider the combined effects of hurricane wind and surge. [ABSTRACT FROM AUTHOR]