Sources Of Coastal Energy

Question 1

1) How is wind energy involved in creating energy in the coastal system?

Answer 1

The suns energy causes different air pressures (due to different rates of heating) which creates wind. The wind then generates waves, the main form of energy at the coast

Question 2

1) how is wind formed?

Answer 2

By air moving between areas of different pressures (from high to low) along a pressure gradient

Question 3

2) how does the STRENGTH OF THE WIND effect wave energy?

Answer 3

The stronger the wind, the more energy the waves have, so they are bigger and more powerful

Question 4

2) how does FETCH LENGHT effect wave energy?

Answer 4

The longer the fetch, the more energy the wave gets as it has longer to gain more energy

Question 5

2) how does DURATION OF THE WIND effect wave energy?

Answer 5

The longer the duration, the more energy the wave has

Question 6

2) which factor effecting wave energy has the greatest impact?

Answer 6

Fetch has the greatest impact on energy because it is the only one that is consistent, it takes long time to change size

Question 7

What are the 4 sources of energy for the coastal system?

Answer 7

1) wind
2) waves
3) tides
4) currents

Question 8

2) how are waves created?

Answer 8

By energy passing through water, causing it to move in a circular motion (but the water doesn’t actually travel in waves, the waves transmit energy

Question 9

2) how are wind - driven waves created?

Answer 9

Created by the frictional drag between wind and surface water… as wind blows across the surface of the ocean, the continual disturbance creates a wave crest

Question 10

2) Why are some areas in the uk subject to powerful waves whilst others arnt?

Answer 10

Some areas have a longer fetch, meaning more energy has been created before coming in land. E.g. the west (specifically SW of uk), Cornwall and Devon see strong waves as the fetch travelled across the vast Atlantic Ocean. The East of the UK sees less powerful waves as the fetch is much shorter (the North Sea)

Question 11

2) what are the two wave types?

Answer 11

Constructive
Destructive

Question 12

2) give some key features of constructive waves:

Answer 12

• strong swash, weak backwash
• add material to the coastline
• low wave with long wave length
• formed by distant weather patterns

Question 13

2) give some features of destructive waves:

Answer 13

• strong backwash, weak swash
• tall in relation to length
• remove material from the coastline
• common during winter storms
• causes cliff face erosion
• generally steep beach profile

Question 14

2) explain the process of constructive waves and what features they form:

Answer 14

They deposit materials like sand and shingle, creating beaches, spits and other depositional landforms such as bars and tombolos

Question 15

2) explain the process of destructive waves and what features landforms they create:

Answer 15

They erode through hydraulic action, abrasion and solution, forming cliffs, caves, arch, stacks, stumps and wave cut platforms

Question 16

3) what are tides?

Answer 16

They are the periodic rise and fall in the level of sea caused by the gravitational pull of the sun and the moon

Question 17

3) what changes on a daily basis to do with the position of the sun and the moon?

Answer 17

The time and the size of

Question 18

3) what are the two types of tides?

Answer 18

Spring tide
Neap tide

Question 19

3) Why are spring tides exceptionally high?

Answer 19

Both the sun and the moon are pulling in opposite directions, pulling further apart, creating a high tide

Question 20

3) why are neap tides very low?

Answer 20

As they are not pulling in the same direction, yet at a right angle, or working against each other, so making the tides low

Question 21

3) Why is knowledge of the tides essential for planning coastal management ?

Answer 21

As you need to build defences that are the right size, so need to know the maximum level of sea water that could rise to in high tides

Question 22

3) what are some impacts of small tidal ranges?

Answer 22

Concentrated erosion

Question 23

3) what are some impacts of high tidal range?

Answer 23

Provides energy via tidal currents, transports sediment = builds up material/deposition

Question 24

What are some features of high energy coastlines?

Answer 24

• Rocky coastline
• many examples in Cornwall
• in the UK they are often Atlantic facing
• contains cliffs/headlands
• erosion exceeds deposition

Question 25

What are some features of low energy coastlines?

Answer 25

• sandy and estuarine
• less powerful waves
• deposition exceeds erosion
• beaches and spits found here
• sheltered area