Satellite-derived sandy shoreline trends and interannual variability along the Atlantic coast of Europe

Monitoring sandy shoreline evolution from years to decades is critical to understand the past and predict the future of our coasts. Optical satellite imagery can now infer such datasets globally, but sometimes with large uncertainties, poor spatial resolution, and thus debatable outcomes. Here we validate and analyse satellite-derived-shoreline positions (1984-2021) along the Atlantic coast of Europe using a moving-averaged approach based on distance and coastline orientation. We show that west-facing coasts and sheltered coasts are more prone to long-term erosion and accretion, respectively. Interannual shoreline variability is influenced by regionally dominant atmospheric climate indices, with coastlines not exposed to the dominant wave climate showing weaker and more variable correlation with the indices. Our results provide a spatial continuum between previous local-scale studies and call for applications based on a relevant averaging approach and the inclusion of coastal setting parameters to unravel the forcing-response spectrum of sandy shorelines globally.