Coasts

Question 1

What sources of energy can create coastal land forms?

Answer 1

Waves
Tides

Question 2

What process occurs in a low energy environment?

Answer 2

Deposition

Question 3

What processes occur in a high energy environment?

Answer 3

Erosion
Transportation

Question 4

Why does wave refraction occur?

Answer 4

Near headlands it is shallower
As a result there is more friction so the slowing effect is greater at headlands

Question 5

What is bathymetry?

Answer 5

The topography of the sea floor

Question 6

Is a beach formed in a high or low energy environment?

Answer 6

Low

Question 7

What can lead to the formation of a beach?

Answer 7

Constructive waves
Longshore drift
Tidal currents
Wave refraction

Question 8

Why are particles on the beach larger at the top?

Answer 8

The backwash does not exert the energy required to move large pieces of matter

Question 9

What is a Dalmatian coast?

Answer 9

When valleys flood

Question 10

Example of a negative feedback loop in relation to coasts

Answer 10

As constructive waves create a steeper beach, the swash exerts less power and the backwash exerts more power which reduces the gradient of the beach

Question 11

How does a saltmarsh form?

Answer 11

When was sediment supply from a river or the tide causes flocculation as the freshwater and saltwater particles mix. This is then colonised by vegetation with a pioneer species such as algae solidifying mud and causing more deposits as the water is slowed down

Question 12

Examples of sub-aerial weathering

Answer 12

Freeze thaw
Chemical weathering
Salt weathering
Wetting and drying

Question 13

Outline the process of chemical weathering

Answer 13

CO2 dissolves in rainwater, forming a weak carbonic acid which reacts with calcium carbonate causing rocks such as limestone to dissolve

Question 14

Outline the process of wetting and drying

Answer 14

Clay gets wet and expands, exerting pressure

Question 15

Outline the process of freeze thaw weathering

Answer 15

As water enters cracks, it may freeze and expand, weakening the rock within a cliff face

Question 16

Outline the process of salt weathering

Answer 16

Salt crystals forms was water evaporates from a cliff face. As the crystals expand, they exert pressure on the rock

Question 17

How do waves erode the coastline?

Answer 17

Solution
Abrasion
Hydraulic Action
Cavitation
Wave quarrying
Attrition

Question 18

Outline the process of abrasion

Answer 18

Bits of rock and sediment smash into the cliff face via the waves

Question 19

Outline the process of hydraulic action

Answer 19

Air in the cracks and faults of cliffs is compressed when waves crash in. This creates pressure, weakening the cliff

Question 20

Outline the process of cavitation

Answer 20

As waves receed, compressed air expands rapidly, exerting pressure on the cliff face

Question 21

Outline the process of wave quarrying

Answer 21

The energy of waves as they hit the cliff is enough to force some of it to break off

Question 22

Outline the process of attrition

Answer 22

Rocks in the water collide with each other and break into smaller bits

Question 23

What is ICZM?

Answer 23

When large areas of the coast are managed with one strategy

Question 24

What is soft engineering?

Answer 24

Working with nature through the management strategy

Question 25

Examples of soft engineering

Answer 25

Managed retreat Do nothing approach Beach nourishment

Question 26

What is hard engineering?

Answer 26

Working against nature through the management strategy Make a physical change to the coastal landscape

Question 27

Examples of hard engineering

Answer 27

Sea walls Groynes Rock armour

Question 28

What do sea walls do?

Answer 28

Dissipate waves energy, reducing the impact of incoming waves Recurved structure throws waves back out to sea

Question 29

How much do sea walls cost per metre?

Answer 29

Approx. £6,000

Question 30

How does rock armour work?

Answer 30

They are large boulders which take the full force of waves which in turn, prevents erosion Rocks aren't secured in place, so they dissipate wave energy of powerful waves as they move about

Question 31

How do groynes work?

Answer 31

They are at a 90° angle from the coast,allowing them to trap sediment

Question 32

What are the disadvantages of groynes?

Answer 32

They can increase erosion further down the coast as they prevent sediment from reaching there, increasing the risk of erosion

Question 33

How does beach nourishment work?

Answer 33

Replacement of material lost through LSD

Question 34

How does dune regeneration work?

Answer 34

There is replanting of species such as marram grass in vulnerable areas and restricted human access to allow for their redevelopment

Question 35

What is a do nothing approach?

Answer 35

Not using defences and letting natural processes unfold

Question 36

What is land-use management?

Answer 36

Planning for future development, e.g. not building important infrastructure on places at risk of erosion and flooding The land can instead be used for easily movable practices such as the grazing of animals