Extreme storm surge induced coastal inundation in Yangtze Estuary regions

Coastal inundation induced by the storm surge belongs to one of the major natural hazards in Shanghai and other regions around the Yangtze Estuary. The worst scenarios of coupling the extreme storm and the sea level rise are presented to assess the storm surge hazard in the Yangtze Estuary. The numerical model MIKE 21 FM is adopted to implement the numerical study, which includes wind, current, tide and wave. The storm surge induced by typhoon 9711 is simulated, and the measurements of six tide gauges are used to validate the numerical model. To identify the worst case scenario of severe typhoon (9711) and super typhoon (5612), we propose seven typhoon tracks through the Yangtze Estuary and fourteen scenarios of landfall time for each typhoon track, which generates 196 cases. Finally, based on the worst case scenario and the relative sea level rise in the range of 0 m to 0.7 m, the coastal inundation maps of Pudong New District and Changxing Island are provided and discussed.