Coast GW1(What are waves and how are they generated+How do waves affect coastal areas)

Coast GW1(What are waves and how are they generated+How do waves affect coastal areas)

1. Parts of a wave

2. Factors affecting wave energy

   • Wind Speed
     • The faster the wind blows,the greater the wave energy is
   • Duration of wind
     • The longer the wind blows,the larger the waves are
   • Fetch
     • Fetch is the distance the wind travelled over seas to from waves.Greater the fetch,greater the wave energy is

3. Waves close to the coastlines

   • 1)Water is shallow.Waves interact with the seabed & change shape(depth=1/2 wave length)
   • 2)Waves continues to move in shallow water.Base of the wave slows down due to friction.Wave height increase wave length decrease.
   • 3)Base of wave stops;wave crest gets taller and topples over.This cause wave to break onto the coast,releasing energy

4. waves on beach

   • Swash
   • Backwash

5. Types of waves

   • Constructive
     • Low gradient
     • Small,low waves
     • Low wave length,long wave height
     • Wave frequency 6 to 8 per min
     • Stronger swash than backwash
     • Swells and spilling breakers
     • Occurs on gentle coastal slope and sheltered coast
     • Deposition process more prominent
   • Destructive
     • High gradient
     • Large,high waves
     • High wave height,short wave length
     • Wave frequency 10 to 14 per min
     • Stronger backwash than swash
     • Occur on steep coastal slope and open coast
     • Erosion process more prominent
     • Plunging & surging breakers

Images and files in the map