- the main driving force of coastal erosion
- can move material onto, off along the shore depend on the height,
length and direction of the waves
-height and length depend on the blows over the water
-Waves that generated by storms, wind or fas moving motor craft can cause coastal erosion
-There are two types of wave
: Constructive wave
: Destructive wave
(click on the image to enlarge)
-High energy waves that erodes the coast
-They are common along the steep sloping coast
-These waves also called plunging breakers where it tend to carry material off the beach and into the sea.
-Produced by waves of short wavelength and high height
-Low energy and are common along gently sloping coasts
-The swash stronger than backwash
-Also called spilling breakers which produced by waves af long wavelength and low height
Corrasion/abrasion is when waves pick up beach material (e.g. pebbles) and gradually erode the coast.
Hydraulic action occur when waves striking a cliff face compress air in cracks on the cliff face this trigger pressure on the surrounding rock, rock crack and remove piece by piece.
Attrition occur when waves cause loose pieces of rock debris (scree) to collide with each other, grinding and chipping result in small size. Scree also collides with the base of the cliff face and have a corrasion effect