PNNL

Abstract

Hurricanes pose a major threat to coastal regions in the United States (US), making it important to understand how the risk associated with them may respond to climate change. In this study, we address this using a suite of numerical models with varying degrees of complexity. Future projections of hurricane activity, downscaled from climate models using a synthetic hurricane model, suggest that the coastal hurricane track density will likely increase over much of the Gulf coast and the lower-East coast by the end of the 21$^{st}$ century with changes in the environmental steering flow playing the dominant role. Further, sensitivity experiments with a stationary wave model indicate that the projected development of an upper-level cyclone over the western Atlantic, which is a part of the baroclinic stationary Rossby wave forced by changes in diabatic heating mainly in the eastern tropical Pacific, may be responsible for the steering flow changes.