Evaluation of surge hazard based on a storm surge hazard indicator along the mainland coast of China

A storm surge hazard indicator was developed based on the storm surge index and high-water index. Using this indicator, the storm surge hazard along the Chinese mainland coast was evaluated. Storm surges were simulated by the GPU-based high-resolution 2-D hydrodynamic operational storm surge model, driven by ERA5 reanalysis data. High waters were calculated from coastal warning water. The results show that the storm surge hazard for more than 80% of the mainland coast is moderate and low. The coasts with high-level storm surge hazard represent less than 20% of the total coast and included the three bays of Bohai, the head area of Hangzhou Bay, in the Pearl River Estuary, the areas along the eastern coast of the Leizhou Peninsula and the coastal area of Guangxi Province. In future work, different sea level rise scenarios will be considered using this indicator and method.