What is coastal erosion?
Coastal erosion is the removal of shoreline sediment or rock by waves, currents and other processes.
Definition and processes
Core concept Waves move sand along and away from a beach; storms can accelerate transport. The balance of incoming river sediment and material removed affects the shoreline. How it is studied Repeated surveys and aerial or satellite images track change. Seasonal beach narrowing should be distinguished from lasting retreat.
Applications and caveats
Why it matters Erosion can threaten settlements, roads and wetlands. Dunes and vegetation may buffer some coasts, while hard structures can alter sediment balance elsewhere. Common misunderstandings Retreat has multiple possible causes, including sea-level change, subsidence and structures. Temporary sand movement is not necessarily permanent loss.