Assessing Future Coastal Flood Hazards From Tropical Cyclones in the Northeastern United States

Coastal flooding from tropical cyclone (TC)-induced storm surges is among the most devastating natural hazards in the US. Accurately quantifying storm surge hazards is crucial for risk mitigation and climate adaptation. In this study, we conduct climatology-hydrodynamic modeling to estimate TC surge hazards along the US northeast coastline under future climate scenarios. In this methodology, we generate synthetic TCs for the northeastern US to drive a hydrodynamic model (ADCIRC) to simulate storm surges. Observing their significant effect on storm surge, for the first time, we bias-correct landfall angles of synthetic TCs, in addition to bias-correcting their frequency and intensity. Our findings show that under the combined effects of sea level rise (SLR) and TC climatology change, historical 100-year extreme water levels (EWLs) along the US northeast coastline would occur annually at the end of the century in both SSP2-4.5 and SSP5-8.5 emissions scenarios. 500-year EWLs are also projected to occur every 1–60 (1–20) years under SSP2-4.5 (SSP5-8.5). SLR is the dominant factor in the dramatic changes in the EWLs. However, while in higher latitudes ((Formula presented.)) TC climatology change modestly affect EWLs ((Formula presented.) contribution for 100-year and (Formula presented.) for 500-year EWL changes), in lower latitudes the impact is more significant (up to 40% contribution to 100-year and 55% for 500-year EWL changes). Extending previous methods, the physics-based probabilistic framework presented here can be applied to project future coastal flood hazards under the effects of SLR and storm climatology change for any TC-prone region.