Characteristics and alongshore variability of sandbar migration on the Chirihama and neighboring beach

Abstract

The characteristics of spatiotemporal variation of the multiple bar system on the Chirihama and neighboring beach, Japan, have been investigated using a set of field surveys collected over 13 years and aerial photographs during 1947 to 2010. In the north and middle of the study area temporal variation of sandbar configuration is characterized by the presence of cyclic cross-shore migration with approximately 4 to 6 years return period. The direction of systematic inter-annual migration is net offshore. The migration features indicate substantial alongshore variability. On the north part the behavior of bar system is quasi two-dimensional. On the middle to south area several three-dimensional configuration and deformation such as bar switching and bifurcation are observed.