Lesson ObjectivesLesson Objectives
This lesson is looking at the different types of wave you can
get and how they effect the coast differently.
By the end of the lesson you should be able to:
• Define the coast .
• Differentiate between three zones of the coast.
• Name the two types of wave.
• Describe the differences between them
• Explain how they change the coastline in different ways.
Constructive and Destructive WavesConstructive and Destructive Waves
• Height = Low (less than 1
• Length = Long
• Frequency = Fewer than 10 a
• Energy = Low
• Beach gradient = flat
• Main process = deposition
• Stronger swash
• Height = High (more than 1
• Length = Short
• Frequency = More than 10 a
• Energy = High
• Beach gradient = steep
• Main process = erosion
• Stronger backwash
Key WordsKey Words
Fetch – the distance a wave has travelled
Swash – the forward movement of a wave up the beach
after the wave has broken
Backwash – water from a breaking wave which flows under
gravity down the beach
Constructive Wave – deposits sediment, building up the
Destructive Wave – a wave that removes sediment from
the beach, eroding it.