Source of Energy

Question 1

What is wavelength?

Answer 1

This is the distance between successive crests.

Question 2

What is a crest?

Answer 2

The highest point of a single wave.

Question 3

What is wave height?

Answer 3

This is the height difference between a waves crest and trough.

Question 4

What is a trough?

Answer 4

The lowest point of a single wave.

Question 5

What is wave frequency?

Answer 5

The time taken for one wave to travel the distance of one wavelength.

Question 6

What do constructive waves do?

Answer 6

They build up a beach resulting in a steeper beach profile, this encourages more destructive waves.

Question 7

Characteristics of constructive waves?

Answer 7

• height = low (1m or less)
• length = long
• frequency = fewer than 10 a minute
• energy = low
• beach gradient = flat
• main process = deposition
• stronger swash

Question 8

What do destructive waves do?

Answer 8

They move material back towards the sea, reducing the beach angle and encouraging more constructive waves.

Question 9

Characteristics of destructive waves?

Answer 9

• height = high (more than 1m)
• length = short
• frequency = more than 10 a minute
• energy = high
• beach gradient = steep
• main process = erosion
• stronger backwash

Question 10

What is wave refraction?

Answer 10

A changing direction of the waves.

Question 11

What are tides?

Answer 11

The regular rising/falling in the level of the sea that differ depending on the time of day and year caused by gravitational pull of the sun and moon.

Question 12

What are spring tides?

Answer 12

Twice in a lunar month (every 29 days), when a moon, sun and earth are in a straight line, the tide rising force is the strongest, thus makes the highest monthly tidal range.

Question 13

What are neap tides?

Answer 13

Also twice a month, the moon and sun are positioned at 90° to each other in relation to the earth, this gives the lowest monthly tidal range.

Question 14

What is tidal range?

Answer 14

The vertical difference between the high tide and the succeeding low tide.
• macrotidal : >4m
• mesotidal : 2-4m
• microtidal :: <2m

Question 15

What is a high energy coast?

Answer 15

Where the waves are powerful for much of the year. Such as Cornwall.

Question 16

What is a low energy coast?

Answer 16

Where the waves are less powerful for much of the year. Such as Lincolnshire.

Question 17

What are rip currents?

Answer 17

Strong currents moving away from the shoreline, they develop when water is piled up along the coastline by incoming waves.

Question 18

What is upwelling?

Answer 18

The movement of cold water deep in the ocean upwards towards this surface, the more dense cold water replaces the warmer surface water and creates nutrient-rich ocean currents

Question 19

What are the sediment sources?

Answer 19

rivers = carry eroded sediment from inland
sea level rise = flood river valleys, forming estuaries
cliff erosion = due to waves, weathering and landslides
waves, tides and currents = transports sediment into the coastal zone.

Question 20

What is a sediment cell?

Answer 20

A stretch of coastline, usually bordered by 2 prominent headlands where the movement of sediment is more or less contained.

Question 21

What is a sediment budget?

Answer 21

The difference between the amount of sediment that enters the system and the amount that leaves is the sediment budget, if more sediment enters than leaves it is a positive sediment budget and overall the coastline builds outwards. If more sediment leaves than enters, its a negative sediment budget and overall the coastline retreats.