Coastal erosion and structural damage due to four consecutive-year major hurricanes: Beach projects afford resilience and coastal protection

This paper presents a forensic analysis of the coastal erosion and structural damage associated with four consecutive-year, Atlantic-basin major hurricanes. The investigation focuses on Hurricanes Matthew (2016), Irma (2017), Michael (2018) and Dorian (2019) and their impact on the sandy shorelines and coastal construction of Florida, located in the southeastern United States. The study identifies the degree of resilience and coastal protection of different coastal construction methods and beach management programs under varied conditions associated with major hurricane impacts. The study results demonstrate a coherent relationship between observed peak storm tide and surveyed measures of coastal erosion and structural damage. The storm tide generated by the natural forcing of tropical-cyclone winds is variably influenced by the wide continental shelf of Florida's gulf coast and the meso-tidal regime of Florida's east coast. As our data show, beyond the obvious metric of storm strength, as expressed in terms of maximum wind speed, coastal impacts by hurricanes are additionally (or more predominantly) driven by storm size, as expressed in terms of wind radii for tropical stormand hurricane-force winds. Of socioeconomic relevance, the results demonstrate that beach management projects of sand placement provide dune and berm protection as well as mitigation against damage to coastal property and infrastructure. The findings of this study are directly relevant to other coastal regions with recreational beach, dense populations and vulnerable infrastructure, subject to erosional and destructive events caused by tropical cyclones.