Coastal Flooding in Floridaˇ¦s Big Bend Region with Application to Sea Level Rise Based on Synthetic Storms Analysis
Author:Scott C. Hagen and Peter Bacopoulos
Flooding is examined by comparing maximum envelopes of water against the 0.2% (= 1-in-500-year return-period) flooding surface generated as part of revising the Federal Emergency Management Agencyˇ¦s flood insurance rate maps for Franklin, Wakulla, and Jefferson counties in Floridaˇ¦s Big Bend Region. The analysis condenses the number of storms to a small fraction of the original 159 used in production. The analysis is performed by assessing which synthetic storms contributed to inundation extent (the extent of inundation into the floodplain), coverage (the overall surface area of the inundated floodplain) and the spatially variable 0.2% flooding surface. The results are interpreted in terms of storm attributes (pressure deficit, radius to maximum winds, translation speed, storm heading, and landfall location) and the physical processes occurring within the natural system (storms surge and waves); both are contextualized against existing and new hurricane scales. The approach identifies what types of storms and storm attributes lead to what types of inundation, as measured in terms of extent and coverage, in Floridaˇ¦s Big Bend Region and provides a basis in the identification of a select subset of synthetic storms for studying the impact of sea level rise. The sea level rise application provides a clear contrast between a dynamic approach versus that of a static approach.