Explain the difference between constructive waves and destructive waves (6 marks)

When the wind blows over the sea, it creates waves. The size and energy of the wave depends on certain factors: the fetch (how far the wave has travelled), the strength of the wind and the amount of time the wind has been blowing. There are two different types of wave - constructive and destructive. They can affect the coastline in different ways. When a wave reaches the shore, the water that rushes up the beach is known as the swash. The water that flows back towards the sea is known as the backwash. The energy of the swash and backwash determine the type of wave.The characteristics of a destructive wave are: weak swash and strong backwash, the strong backwash removes sediment from the beach and the waves are steep and close together. The characteristics of a constructive wave are: strong swash and weak backwash, the strong swash brings sediments to build up the beach, the backwash is not strong enough to remove the sediment and the waves are low and further apart.