2024 Volume 80 Issue 17 Article ID: 24-17045
This study conducted a pseudo-global warming typhoon track ensemble experiment (condition RCP8.5 scenario, end of 21st century) based on Typhoon Hagibis (2019) for Ise Bay and Mikawa Bay to evaluate compound flooding characteristics caused by typhoon-related storm surge and heavy rainfall. Track ensemble experiments of 20 cases each for the present and future climates revealed that inundation occurred in several cases in both Ise Bay and Mikawa Bay in the future climate. The maximum storm surge anomaly was 4.3 m at the Port of Nagoya and 3.1 m at the Port of Mikawa in the cases similar to Isewan Typhoon (1959). Sensitivity experiments regarding river discharges showed that when both storm surge and river discharge are considered (compound hazard), the inundation area and averaged inundation depth increase by approximately 40% and 20%, respectively, compared to the results for storm surge alone. Evaluating storm surge and river flood separately may underestimate the impacts of compound hazards. Especially in the Ise Bay estuary, it is important to consider the river flood peaks after the passage of typhoons in large rivers such as the Kiso River.
