抄録
A large scale of salinity stratification is generated in Isahaya Bay after a large amount of river water was discharged into the inner area of the Ariake Sea and the stratification disappears after the discharge decreased. In this paper, the disappearance processes are investigated by using a 3-D flow simulation model for the Ariake Sea. The behaviors of the low salinity water mass obtained by the numerical analysis agree well with those observed by Kyushu Regional Agricultural Administration Office. A large scale of salinity stratification in Isahaya Bay generates and disappears through the process that the low salinity water mass flows into along the west coast of the Ariake Sea and out along the Simabara Peninsula.