Slides in this set
The formation of waves
Wind blowing over the seas surface causes small ripples which grow into
waves. Waves are responsible for most of coastal erosion. When a wave
approaches the coast its lower part is slowed by friction with the sea bed,
whereas the upper part continues to move forward the terms "breaking
waves" is used. As it is left unsupported it topples over and breaks forward
against the cliff face or up the beach. There are two types of waves:
· Destructive waves- waves which erode most
· Constructive waves (addressed later on in powerpoint when looking at
Longshore drift and deposition)…read more
These waves have three main features:
-They are high in proportion to their length.
-The backwash is much stronger than the wash therefore rocks, pebbles and
sand are pulled back into the sea.
-They are more frequent than constructive waves breaking at an average of
between eleven and fifteen per minute.
The height and destructiveness of these waves depends on the distance
over which these waves have travelled and the wind speed or fetch. If the
waves have travelled over a long distance they have had time to build up
therefore a lot of energy is released when they reach the coast.
Fetch- is the length of water of which the wind has blown. The greater the
fetch and the stronger the wind, the more powerful the wave and
essentially the more destructive.…read more
The weight and impact of the water against the coastline.
Much greater under storm conditions when hundred of tonnes
of water may hit the cliff face. Air trapped in cracks and caves is
compressed by the waves increasing the pressure on the rock.…read more