Short-Term Change of Offshore Sand Bar Topography along Tottori Coast

Abstract

The present study deals with a short-term change on-offshore sand bar topography along Tottori coast. The observations were made applying ARGUS method. The sand bar shows year around change characteristics. In late autumn, shore line and offshore sand bar are very smooth and straight. In winter, storm waves bring cusping geographical feature and the offshore sand bar shows concavo-convex features with convexity at bay and concave at horn locations on the shoreline. From spring to autumn, these concavo-convex features gradually disappear. The amplitude of these features are relevant to the integrated values of wave energy minus threshold wave energy, which may be necessary to generate rip current with sufficient velocity