Method for Estimating Future Hurricane Flood Probabilities and Associated Uncertainty

Abstract

Reliable hurricane flood probability estimates are essential for effective management and engineering in the coastal environment. However, uncertainty in future climate conditions presents a challenge for assessing future flood probabilities. Studies suggest that in the future, sea-level rise may accelerate, and hurricanes may intensify and occur less or more often. Here, methods are presented for incorporating sea-level rise and future hurricane conditions into extreme-value flood statistics analysis. By considering an idealized coast, surge response functions are used with joint probability statistics to define time-varying continuous probability mass functions for hurricane flood elevation. Uncertainty in the flood estimates introduced by uncertainty in future climate is quantified by considering variance in future climate and sea level projections. It will be shown that future global warming can increase the flood elevation at a given return period by 1–3% per decade, but that climate-related uncertainty only marginally contributes to the overall uncertainty associated with hurricane flood statistics. Finally, it will be demonstrated that adaptive management practices are the most effective means of optimizing future coastal engineering activities in the face of climate change.