Summary Geography Unit 1C — Coasts

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GCSE GEOGRAPHY
Coasts
notebooklet
Paper 1 Section C

, wave ripples in the sea caused by the transfer of energy from the wind blowing
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on the surface of the sea or dramatic tectonic activity (such as earthquakes or
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volcanic eruptions)
Formation of a wave:
1 the wave develops a circular orbit in open water
2 friction with the seabed disrupts the circular movement of the water
3 the circular motion becomes increasingly elliptical - causes crest of the wave to
move faster
I the crest of the wave collapses onto the beach as the wave breaks
5 water rushes upto the beach - the swash
6 water from previous wave moves back towards the sea - the backwash

distance between
↑ wave crests
the wave
wavelength wave-top

M
↑ crest
↳ rises and steepens
height S
I
-
b
wave "
wavebreales

&
_
Y
· SWASt




g
e
R




-
_ a
a
BACKWASA
seabed ↓L
circularbit




TIVEWaves
DESTRUCIVE Waves

‘spilling’
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formed by storms close to the
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formed by storms often 100s of coast
km away high wave height
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low wave height -
short wave length
I
long wavelength /
weak swash
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powerful swash -
strong backwash
weak backwash high and steep build up; plunges
. deposits sand and pebbles and
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down onto beach and ‘destroys’ it
‘construct’ the beach (makes it ·
removal of sand and pebbles
wider and flatter)