Longshore Drift is the movement of sediment along a coastline.
How is a coastal spit formed?
Waves approach the beach at an angle due to the prevailing winds. The waves carry sand and sediment down the coastline with the swash and backwash. This process is known as longshore drift. When there is a change in the direction of the coastline (e.g: at a bay) the sediment is deposited in shallower water and weaker currents. The longshore drift process of deposition continues and the sediment forms up to build new land. This is called a spit. When the wind changes direction, this can curve the end of the spit. Behind the spit is sheltered from the waves so mudflats + salt marshes form. This can be seen in Hampshire where the hurst castle spit is formed.
If the spit builds up, eventually joins up to the other headland, this becomes a coastal bar. If it joins from the headland to an island, this is called the tombolo.
Coastal management in the UK
The departement for environment, food and rural affairs (Defra).
The coastline is divided into 11 areas called sediment cells, each cell is divided into smalled cells, each subcell has a shoreline management plan.
The wearing away of rocks by the action of the sea.
The breaking down of rocks by the action of the weather, plants or chemical action.
Two types of waves
Destructive waves: Removing the beach
Constructive waves: Building the beach