Slides in this set
Introduction to coasts.
What is a coast: A coast is a zone where the land
meets the sea.
Waves are the primary force causing erosion along
coastlines. A wave is formed by the wind blowing
across the surface of the water, creating ripples,
which then grow into waves. As waves reach the
coast the lower section slows due to friction. The
upper section topples over and breaks forward.…read more
The size of waves depends on:
The wind speed
The length of time during which the wind blows in the
The length of sea over which the wind blows. The
greater these factors are the bigger the wave.…read more
Constructive Waves have a number of important
i) Their swash is much stronger than their backwash,
causing the beach to be built up by the deposited
ii) They are less frequent, reaching shore between 6 and
8 times each minute.
iii) They are long waves and so roll onto the beach rather
than crashing onto it.
iv) Constructive waves create a wide, gently sloping
Destructive Waves have a number of important
i) Their backwash is much stronger than their swash,
thus allowing them to remove material from the beach.
ii) They are frequent in number, usually between 10 and
15 per minute.
iii) They are tall waves, meaning they have a greater
distance to fall when they break. This causes them to
scour out the beach material.
iv) Destructive waves create a steep narrow beach…read more