HINDCASTING OF SURGE AND WAVE ON HOKKAIDO COASTS BY WINTER LOW PRESSURE SYSTEM USING SURGE-WAVE COUPLED SEA BOTTOM AND SURFACE STRESSES IN SUWAT

Typhoon-induced storm surge can cause catastrophic consequences in low-lying city areas on coasts. From the historical observations, it is found that Winter Low Pressure System (WLPS) has impacts similar to a typhoon in terms of surge and wave generation. For instance, from 16th to 17th in December 2014, a winter low pressure system of 951 hPa occurred in Hokkaido, Japan, generated a surge of 1.75 m high and flooded many low-lying regions on the Kushiro coast. This was the record-break surge level due to WLPS in Japan, since the WLPS-induced surge of 0.9 m was recorded in 1994.