Attrition is when waves cause rocks and pebbles to bump into each other and break up.

Find out more about coastal erosion.

Beaches, sand dunes, spits and bars.

Find out more about landforms of coastal deposition.

Waves hitting the base of a cliff causes leads to air compression in cracks, joints and folds in bedding planes, causing repeated changes in air pressure. As air rushes out of the crack when the wave retreats, it leads to an explosive effect as pressure is released. This process is supported further by the weakening effect of weathering. The material breaks off cliffs, sometimes in huge chunks. This process is known as hydraulic action.

Find out more about coastal erosion.

Coastal erosion is the wearing away of the land by the sea.

Find out more about the processes of coastal erosion.

Freeze-thaw weathering occurs when rocks are porous (contain holes) or permeable (allow water to pass through). Water enters the rock and freezes. The ice expands by around 9%. This causes pressure on the rock until it cracks. Repeated freeze-thaw can cause the rock to break up.

Find out more about weathering.