Action of the waves
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).
destructive and constructive waves
- destructive waves are created in storm conditions.
- are created from big, strong waves when the wind is powerful and has been blowing for a long time.
- occur when wave energy is high and the wave has travelled over a long fetch.
- tend to erode the coast.
- have a stronger backwash than swash.
- have a short wave length and are high and steep.
- constructive waves are created in calm weather and are less powerful that destructive waves.
- break on the shore and deposit material, building up beaches.
- have a swash that is stronger than the backwash.
- have a long wavelength, a low height.