Hindcasts of the coastal impact of Hurricane Ivan on Santa Rosa Island, Florida, using a storm-impact scaling model that compares hurricane-induced water levels to local dune morphology, were found to have an accuracy of 68% in predicting the occurrence of one of four impact regimes: swash, collision, overwash, and inundation. Errors were overwhelming under-predictions of the regime where the observed response was more extreme than had been expected. This is related to the evolution of the profile during the storm. Mean pre-storm dune elevations decreased by 1.9 m over the 75-km long island as most of the dunes were completely eroded during the storm. Dramatic morphologic change during a hurricane makes barrier islands more vulnerable to overwash and inundation than will be predicted based on pre-storm dune parameters. Incorporation of the timing of rising water levels relative to storm-induced profile evolution is required to improve model accuracy.
Additional Publication Details
Hindcasting potential hurricane impacts on rapidly changing barrier islands
American Society of Civil Engineers
Coastal and Marine Geology Program
Larger Work Title:
Coastal Sediments '07 - Proceedings of 6th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes
6th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes