ABSTRACT
ABSTRACT: This paper suggests a methodology for hazard-specific/risk-consistent hurricane event characterization. Typically, the hurricane hazard is described in terms of maximum wind speed Vmax (at the eye-wall), since damage descriptors associated with intensity scales (e.g., the SaffirSimpson Hurricane Scale) and collateral hazards (e.g., hurricane surge) are related most often to maximum wind speed. However, recent studies have shed light on the importance of storm size (i.e., radius of maximum winds, Rmax) in describing the hurricane wind field and thus the spatial extent of potential damage. The large losses from several recent hurricanes underscore the need for better understanding the impact of storm size on damage. To that end, we seek to develop parameter combinations (e.g., Vmax and Rmax) that define “characteristic” risk-consistent hurricane events in one particular geographic region. A simulation framework is developed to generate 10,000 years of simulated hurricane events and a synthetic hurricane wind speed database for the state of Texas, using state-of-the-art hurricane modeling techniques and information extracted from historical hurricane data. The resulting 10,000 years database, which includes information developed for every zip-code in Texas, includes time of hurricane passage, maximum gradient wind speed and surface wind speed. Using this simulation framework, selected parameters (i.e., intensity and size parameters) are recorded for each hurricane at the time of landfall along the Texas coast. Using a hurricane decay model specifically calibrated for this location, parameters Vmax and Rmax at inland locations also are recorded. The critical values of Vmax and Rmax are then selected to jointly describe the intensity and spatial extent of hurricanes and the joint histogram is developed. Finally, these variables are statistically characterized and a suite of the characteristic hazard events (Vmax and Rmax combinations) corresponding to certain hazard levels are identified. The proposed methodology for event-based hurricane hazard characterization, when coupled with a hurricane damage model, can be used for regional loss estimation and other spatial impact analyses. The proposed approach also can be used to develop characteristic hazard
(ii) the angle of impact at landfall θ; (iii) the central pressure cp; (iv) the forward speed during final approach to shore vf; and (v) the radius of maximum winds Rm. These variables ultimately constitute the model parameters vector, x, describing each hurricane scenario. The variability of the hurricane track and characteristics prior to landfall is approximately addressed by appropriate selection of the hurricane track history prior to landfall, so that important anticipated variations are efficiently described.
