Recent shoreline mobility and geomorphologic evolution of macrotidal sandy beaches in the north of France

This paper examines shoreline mobility and sediment budget conditions on a sandy macrotidal coast with a well developed foredune. Aerial photographs and ‘bunker archaeology’ covering the last 50 years were analysed in order to determine the meso-scale evolution of Le Touquet beach, in northern France. Both methods show that shoreline retreat has been negligible or very slow and has been accompanied by an elevation of the foredune. DGPS cross-shore profiles show a balanced sediment budget over the last 7 years. Only a slight change of the beach face profile (0.2–0.5 m rise or fall) was observed while the foredune exhibited a sharper change. The French coast of the eastern English Channel differs from that of the French Atlantic coast which is currently being strongly eroded. The balanced sediment budget of the former is attributed to sand inputs from nearshore banks, which compensate exports due to longshore drift and to foredune development.