Hong Kong’s extensive coastline and dense economic development render it highly vulnerable to tropical cyclone-induced storm surges, a risk exacerbated by projected global warming and rising sea levels over the 21st century. This study pioneers the use of a very high-resolution (100-m) air-wave-ocean coupled model, integrating convection-resolving atmosphere and three-dimensional ocean components, to project worst-scenario storm surges in Hong Kong by the 2040s, within the period in the next twenty years that decision-makers and stakeholders are most concerned with. Three experiments simulate Typhoon Mangkhut (2018) under distinct conditions: (1) FutureWarming, assessing upper-bound atmospheric and oceanic warming; (2) StraitTraveler, modeling a trajectory bypassing Luzon Island; and (3) Combo, combining both factors. Results project storm surges exceeding astronomical tides by approximately 4. 0 m in Victoria Harbour, 5. 2 m in Deep Bay, and 6. 2 m in Tolo Harbour, with Tolo Harbour potentially experiencing multiple flooding peaks within 12 hours due to the seiche effect, which has not been reported in the past. These findings, among the first to leverage such high-resolution and fully coupled configurations, highlight the critical need for enhanced monitoring, infrastructure resilience, and robust disaster preparedness to mitigate the escalating socioeconomic impacts of future storm surges in Hong Kong.
Li et al. (Sun,) studied this question.