Assessing Climate Change Impact on the Joint Wind-Rain Hurricane Hazard for the Northeastern U.S. Coastline

In this chapter, we present results of a study to assess the impact of possible future climate change on the joint hurricane wind and rain hazard along the US eastern coastline. To characterize the hurricane wind hazard, climate change scenarios were coupled with simulation-based hurricane genesis, wind field, and tracking models to examine possible changes in hurricane intensity (maximum wind speed) and hurricane size (radius to maximum winds). A number of different postulated climate change models (IPCC scenarios) were considered. Each scenario suggested changes in sea surface temperature (SST), the driving parameter in most modern hurricane wind field models. The evolution of hurricane genesis frequency and hurricane track behavior were examined, though no temporal trend was apparent in either. A rainfall hazard model was then developed using recorded rainfall data associated with hurricane events and a probabilistic model relating wind and rain was constructed. The pairwise joint distributions of maximum wind speed, spatial extent/storm size, and maximum rainfall rate—under current and future climate scenarios—were developed and compared. Finally, joint multivariate (wind speed intensity, spatial extent/storm size, rainfall rate) distributions were constructed to describe the joint wind-rain hurricane hazard including consideration of projected climate change impacts. Implications for current and future design (code provisions) are discussed.