Abstract
The Tsugaru Strait lying between Hokkaido and Honshu islands of Japan is one of the most powerful site for tidal and ocean energy. Field observations on the velocity field of this site revailed significant increase in the velocity flutuation may occur in summer and autumn. This study conducted a numerical experiment on the effects of the density stratification on the velocity field in the strait. Density stratification was found to strengthen and elongate a wind-driven flow, resulting in significant velocity disturbance near the surface.