This study carried out along the macrotidal coast of northern France revealed a high spatial and temporal variability in shoreline evolution at different time scales. Beach-dune topographic profiles surveyed during two and a half years showed that storms can be responsible for significant but variable morphological changes along the coastline. Where dunes are eroding, erosion is not only controlled by the intensity of individual storms, but also strongly depends on the duration of storm events, which determines the length of time during which coastal dunes can be reached and eroded by waves. At a longer time scale (decadal scale) phases of extensive dune erosion and coastal retreat are only associated with periods of high frequency of high water levels, but also with higher frequencies of long-lasting, moderate to strong, northerly wind events during which large incident storm waves can be generated.
