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:

• Hydraulic action. Air may become trapped in joints and cracks on a cliff face. When a wave breaks, the trapped air is compressed which weakens the cliff and causes erosion.
• Abrasion. Bits of rock and sand in waves grind down cliff surfaces like sandpaper.
• Attrition. Waves smash rocks and pebbles on the shore into each other, and they break and become smoother.
• Solution. Acids contained in sea water will dissolve some types of rock such as chalk or limestone.