Destructive Waves

AQA GCSE Geography > Physical Landscapes in the UK > Coastal Landscapes in the UK > Destructive waves

What are destructive waves?

Destructive waves destroy beaches. The waves are usually very high, have a short wavelength and are very frequent. They have a steep front and are typically over 1 metre tall. As destructive waves approach the coast, they gain height, plunge onto a steep beach, and do not travel far up it. The swash is very weak, whereas the backwash is strong. This leads to a net loss of beach material. Although a destructive wave’s swash is much stronger than a constructive wave, its backwash is much weaker than its swash. These waves can transport beach material back into the sea, creating a steep beach profile.

They are more common in winter than in summer and are usually found in more exposed areas. The force generated by a destructive breaking wave can erode a headland.

The characteristics of a destructive wave

Summary

What are Waves?
Waves are sea or ocean surface disturbances, forming moving ridges or swells.
How are Waves Formed?
Waves are created by the wind transferring energy to the sea through friction; this makes the water move.
Water Movement
In deep water, water molecules move in circles; near the coast in shallow water, the water itself moves forward.
Why Some Waves Are Stronger?
Wave size depends on fetch (the distance the wave travels), wind speed, and how long the wind blows.
Wave Behaviour Near Shore
In shallow water, waves slow at the base, tilt forward, break, and move towards the shore.
Types of Waves
Waves can be either constructive (building up beaches) or destructive (eroding beaches).