coastal erosion definition geography
Coastal erosion. The sea shapes the coastal landscape. Coastal erosion is the wearing away and breaking up of rock along the coast. Destructive waves erode the coastline in a number of ways: 1  Hydraulic action.2  Air may become trapped in joints and cracks on a cliff face. 3  When a wave breaks, the trapped air is compressed which weakens the cliff and causes erosion.4  Abrasion.oastal erosion is the wearing away and breaking up of rock along the coast. Destructive waves erode the coastline in a number of ways: 1  Hydraulic action. 2  Air may become trapped in joints and cracks on a cliff face. 3  When a wave breaks, the trapped air is compressed which weakens the cliff and causes erosion. 4  Abrasion.