Sources of energy at the coast

Question 1

What is the main energy source for coasts?

Answer 1

Waves which are formed offshore

Question 2

How are waves formed?

Answer 2

Wind moves across the water causing frictional drag which creates small ripples and waves. This leads to a circular orbital of water.

As the seabed turns shallower, the circular orbits turn elliptical leading to horizontal wave movement

Wave height increases, wavelength decreases

Water backs up behind the wave until it collapses and surges up the beach

Question 3

How does the strength of the wind affect wave energy?

Answer 3

Large pressure gradient, strong winds.
Stronger winds means stronger waves

Question 4

How does the duration of the wind affect wave energy?

Answer 4

If the wind is active for a longer time, the energy of the waves will build up and decrease

Question 5

What is fetch?

Answer 5

Distance over which the wind blows

Question 6

How does the size of fetch affect wave energy?

Answer 6

The bigger the fetch, the stronger the wave energy

Question 7

what is the difference between high pressure and low pressure

Answer 7

High pressure: air sinks
Low pressure: air rises