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The coastal zone- Waves
What is the coast?
The coast is a narrow zone between land and sea. It is a constantly changing area due to
erosion and wave action.
Constructive waves have a powerful swash. They carry large amounts of sediments and
create the beaches. The waves are well spaced apart and are powerful when they reach
the coast. They are formed by distant storms.
Destructive waves have a powerful backwash, and a weal swash. The powerful backwash
pulls sand off the beach. They are closely spaced and often interfere with each other,
producing a chaotic, swirling mass of water. They are formed by close storms.
Crest- The top of a wave
Swash- The forward movement of a wave
Backwash- The backward movement of a wave