Monitoring shoreline rotation with a coastsnap system at the mesotidal embayed beach of Lafitenia, France

International audience; Shoreline position varies over a wide range of temporal and spatial scales in response to a variety of processes. The monitoring of its position changes requires availability of high-frequency observations over a long period. In this study, the low-cost crowd-sourced system CoastSnap (Harley et al., 2019) is used to investigate the shoreline dynamics at the embayed beach of Lafitenia over a 9months period. After the validation of CoastSnap images rectification thanks to in situ surveyed data, a quantitative analyse of cross-shore position changes is undertaken using high tide waterline. The obtained results show apparent short time scale beach rotation for the first time at Lafitenia. This new shoreline mapping approach offers new perspectives to study short time coastal processes over long periods.