MORPHOLOGICAL CHANGES OF SHORELINE AND OFFSHORE BARS ALONG TOTTORI COAST

The present study deals with a short-term change of a coast line and a sand bar system along Tottori coast. The observations have been made applying Argus method. The coast line and sand bars show year around change feature. In late autumn, the shore line and inner bar are very smooth and straight. In winter, high waves bring cusping feature on the shore line and the concavo-convex feature on the inner bar with offshore convexity at bay and shoreward concavo at horn locations. These features on the shore line and the inner bar are opposite in phase. Rip channels develop from the cusp bay. From spring to autumn, these features gradually diminish. While an outer bar shows crescentic feature with an offshore convexity all year round. Its amplitude slightly reduces in winter and extends from spring to autumn. Change of these features, beach cusp and convexity of inner and outer bars, seems quite different from existing bar state models.