Sandy beaches occupy more than one-third of the global coastline and have high socioeconomic value related to recreation, tourism and ecosystem services.
Beaches are the interface between land and ocean, providing coastal protection from marine storms and cyclones. However the presence of sandy beaches cannot be taken for granted, as they are under constant change, driven by meteorological, geological and anthropogenic factors. A substantial proportion of the world’s sandy coastline is already eroding, a situation that could be exacerbated by climate change. Here, we show that ambient trends in shoreline dynamics, combined with coastal recession driven by sea level rise, could result in the near extinction of almost half of the world’s sandy beaches by the end of the century. Moderate GHG emission mitigation could prevent 40% of shoreline retreat. Projected shoreline dynamics are dominated by sea level rise for the majority of sandy beaches, but in certain regions the erosive trend is counteracted by accretive ambient shoreline changes; for example, in the Amazon, East and Southeast Asia and the north tropical Pacific. A substantial proportion of the threatened sandy shorelines are in densely populated areas, underlining the need for the design and implementation of effective adaptive measures.
The models and datasets presented are part of the integrated risk assessment tool LISCoAsT (Large scale Integrated Sea-level and Coastal Assessment Tool) developed by the Joint Research Centre of the European Commission.