Extratropical Storm Surge
From 16th to 17th in December 2014, a winter low pressure system in Hokkaido, Japan, generated a surge of 1.75 m high and flooded on many low-lying Kushiro coasts. The study carried out a series of numerical simulations using a coupled model of surge, wave and tide with the two-level domains. SuWAT considered a wind speed-limited wave dependent drag and a wave-surge interacted bottom roughness drag. The results indicate that the coupled model could estimate the observed surge and wave levels using the wave-surge interacted bottom drag as well as the capped-wave dependent drag at 25-30 m/s.