Аннотация:The BG model (a three dimensional model for predicting beach changes based on Bagnold's concept) was applied to the prediction of the three dimensional topographic changes of a sandy island due to waves, which was obtained by a movable bed experiment by Uda and Yamamoto. In Okhotsk Sea, Taketomi Island was formed as an island composed of sand by a volcanic eruption and then, the island was markedly deformed by wave action, resulting in forming a double tombolo behind the island (Zenkovich, 1967). The model was also applied to these topographic changes of the island. The predicted and measured topographic changes in two examples were in good agreement.
