Bitesize has changed! We're updating subjects as fast as we can. Visit our new site to find Bitesize guides and clips - and tell us what you think!
Print

Geography

Coastal processes

Page:

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  1. Next

Coasts are shaped by the sea and the action of waves. The processes that take place are erosion, transportation and deposition.

The action of waves

The power of waves is one of the most significant forces of coastal change. Waves are created by wind blowing over the surface of the sea. As the wind blows over the sea, friction is created - producing a swell in the water. The energy of the wind causes water particles to rotate inside the swell and this moves the wave forward.

The size and energy of a wave is influenced by:

  • how long the wind has been blowing
  • the strength of the wind
  • how far the wave has travelled (the fetch)

This activity shows the length of fetch along the south coast of England:

Waves can be destructive or constructive.

When a wave breaks, water is washed up the beach - this is called the swash. Then the water runs back down the beach - this is called the backwash. With a constructive wave, the swash is stronger than the backwash. With a destructive wave, the backwash is stronger than the swash.

Page:

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  1. Next

Back to Coasts index

BBC navigation

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.