Wave type and wave refraction - COASTS

Question 1

Constructive waves

Answer 1

Formation:
-distant wether systems generate these waves in the open oceans

Wave form:
-low surging waves
-long wavelength
-low frequency

Wave break:
Strong swash/ weak backwash
-beach gain

Beach profile:
- gentle beaches

Question 2

Destructive waves

Answer 2

Formation:
-local storms are responsible for these waves

Wave form:
- high plunging waves
-short wavelength
-high frequency

Wave break:
-weak swash/strong backwash

-Beach loss

Beach profile:
-steep beaches

Question 3

Wave refraction

Answer 3

• The topography (shape) of the coastline determines the effects of wave action.
• When a wave approaches a coastline that is irregular in shape it is refracted and becomes increasingly parallel to the coastline.
• Energy of the wave is concentrated at the
  headland and dissipated in bays.
• This accounts for the presence of erosive
  features (caves, arches, stacks) on headlands and depositional features (beaches) in bays
• Waves approaching the headland encounter shallower water sooner.
• But the part of the wave in the bay is still in deeper water.
  Friction with the sea floor slows the headland approaching waves and causes their frequency to increase.
• In the bay, waves are less frequent and have less energy