Coastal landscapes

When waves carrying sediment loose energy and slow down

Breakdown of rock without changing its chemical composition. e.g; freeze thaw weathering.

Breakdown of rock by changing its chemical composition. eg; carbonation

When temporary sea level rises becuase strong winds push water onshore

When waves erode the coast

When waves deposit material

Waves crash again rock and compress air in the cracks. This puts pressure on the rock. Repeated compression widens the cracks and causes bits of rock to break off.

Eroded particles in the water scrape and rub against rock, removing small pieces.

Eroded particles in the water collide, break into smaller pieces and become more rounded.

Large particles like boulders are pushed along the sea bed by the force of water

Small particles like silt and clay are carried along in the water

Pebble sized particles are bounced along the sea bed by the force of water

Soluble materials like limestone dissolve in the water and are carried along

Man made structures built to control the flow of the sea and reduce flooding and erosion

Schemes set up using knowledge of the sea and its processes to reduce the effects of flooding and erosion.

A wall made out of hard material like concrete that reflects waves back to sea

Prevents erosion of the coast and acts a barrier to prevent flooding

It creates a strong back wash that erodes under the wall and expensive to maintain

A wall of wire cages filled with rocks, usually built at the foot of cliffs

Absorb wave energy, reducing erosion. They’re cheap and easy to build.

They’re ugly to look at and wire cages erode over time

Boulders that are piled up along the coast

Absorbs wave energy, reducing erosion and flooding and a cheap defence.

Wooden or stone fences that are built at right angles to the coast. They trap material transported by longshore drift.

They create wider beaches which slow the waves. This gives greater protection from flooding and erosion and fairly cheap.

They starve beaches further down the coast of sand making them narrower. Narrow beaches don’t protect them well leading to greater erosion

Sand and shingle from the sea bed or lower down the beach added to upper part of the beach

It creates wider beaches which slow down the waves. This gives greater protection from erosion and flooding

Taking material from the sea bed can kill organisms like sponges or corals. it’s very expensive and has to be repeated to maintained

Creating or restoring sand dunes through nourishment or planting vegetation to stabilise the sand

Creates a barrier between land and sea and absorbs wave energy preventing flooding and erosion and stabilisation cheap

This protection is limited to a small area and nourishment is expensive