Sand Ripples and Bedforms
The Kanmon waterway is one of the most important international routes in Japan. In the waterway, sand waves, which may hamper the ship navigation, develop on the bottom at some places. In this study, the characteristics and cause of the sand waves in the waterway were investigated. The results imply that the long-term fluctuation of tidal currents accompanied by the long-term fluctuation of sea level departure affects the development of sand waves, and that the path variation of Kuroshio (a major warm current) causes the long-term fluctuation of sea level departure in the waterway.