Measurements of bed level oscillation cycles in the surf zone of a sandy beach

Abstract

High frequency bed level measurements have been realized during several tide cycles, on the beach face of a meso-macro tidal sand beach on the Aquitanian coast (France). A network of seven instruments, using a resistive method to monitor bed level changes, recorded up to 57 tidal cycles. Data are analysed and interpreted with respect to wave and tide conditions recorded with pressure sensors deployed in the same area. Bed level evolution is analysed and compared with disturbance depth. The comparison demonstrates the ability of the system to characterize real-time response of bed level to wave forcing in the surf and swash zones under energetic waves and shows different patterns of bed level response depending on tide phase and location on the beach face.