Drivers of coastal cliff erosion in Denmark

Denmark has an 8,750 km long coastline with a heterogeneous set of coastal cliffs in previously glaciated landscapes. The erosion of those cliffs is a complex interplay between a number of marine, coastal, terrestrial, anthropogenic and atmospheric factors. Currently, we lack a basic understanding of processes leading to cliff erosion and factors influencing coastal cliffs morphology. In this study, we delineate cliff profiles along all the shores of Denmark and combine the morphological indices of those cliff profiles with coastal environmental factors. Most cliffs are located in areas of Weichselian glacial deposits and they show different cliff morphologies than those in pre-quaternary bedrock outcrops. The highest rates of cliff top and cliff toe change are observed at the west coast of Denmark, where cliffs are consisting of sand and are exposed to high-energetic wave conditions from the North Sea. To protect coastal communities effectively, it is crucial to better understand the processes that drive coastal cliff erosion and its associated erosion rates.