Coastal Environments

Question 1

How is an arch formed?

Answer 1

The destructive waves hit the headland till a crack forms which then erodes away till there is an cove and then eventually it will crumble and form an arch.

Question 2

What type of coastline is needed to form headlands and bays

Answer 2

A discordant coastline

Question 3

How do waves effect the costal land forms?

Answer 3

Constructive waves build up the beach making the profile steeper

Destructive waves have a strong backwash and erode the beach giving it a flat beach profile

destructive waves can also lead to arches stacks and stumps forming, as they can erode the headlands causing them to crack and fall apart

Question 4

How does weathering affect the coastal landforms

Answer 4

chemical weathering - when minerals in the rock react with the salt water from the sea or precipitation, causing it to erode and become weaker.

physical weathering - e.g. freeze thaw weathering, precipitation will seep into the rocks and then freeze and expand, causing the rocks to crack and split. the ice will then melt an the cycle will start again.

biological weathering - when animals or plants burrow into the crack of rocks, causing them to crack a split further

Question 5

How does pollution affect coastal landforms

Answer 5

rising temps can cause oceans to absorb more CO2 which means that the oceans are becoming more acidic and this can lead to more chemical weathering.

Question 6

How does buildings affect coastal lands

Answer 6

Surface runoff can flood the surrounding landforms and erode them

Question 7

How does coastal uplift effects the coastal landforms

Answer 7

Underwater earthquakes can cause tsunamis which can destroy beaches and coastal towns

Question 8

How do rivers affect coastal landforms

Answer 8

Could transport sediment from land to the coastal zone. Sediment might contribute to beaches and depositional land forms

Question 9

How does rock type effect CLF

Answer 9

Discordant coastline is I’ll crest headlands and bays
weaker rocks such as clay will erode faster than stronger rocks such as granite, sandstone and chalk.

Question 10

How does coral reef effect CLF

Answer 10

It acts as a buffer and absorbs some of the waves energy, which prevents destructive waves from being able to reach the shore and destroy the beach.

Question 11

How does climate change effect CLF

Answer 11

Melts the glaciers which increases eustatic sea levels. This creates submergent features also increases likelihood that cliffs will be eroded.
alternatively if the isostatic sea level falls due to land rebound when glaciers melt, creating emergent features.
more CO2 in the atmosphere leads to oceans absorbing more CO2 which can be very harmful to marine biodiversity.

Question 12

outline the processes that form barrier beaches [4 marks]

Answer 12

a barrier beach is formed when a spit is extended along a bay.
longshore drift will transport sediment along the coastline, until it changes in shape. A spit will then develop within a bay, until it forms a barrier of sediment that blocks water from flowing out of the bay.
colonisation of plant such as marram grass and salt wart, will consolidate the bar of sediment, allowing it to become more stable and stay above sea level even during high tides or storms.

Question 13

Explain the development of saltmarsh environments [4 marks]

Answer 13

salt marshes occur in sheltered estuaries behind spits. the river can deposit sediment, allowing it to become an inter tidal mudflat. the mudflat continues to build and rise above sea level. Then halophytic vegetation can then colonise the marsh and trap more sediment.

Question 14

outline the process of coastal hydraulic action [4 marks]

Answer 14

hydraulic action is a marine process. it is the action of the sheer force of the water alone with no debris. Hydraulic action forces water into the side of cliffs, which makes the rock weaker and erodes the rock. this is sometimes known as wave quarrying.

Question 15

2020 - Outline the process of sub-aerial weathering in the development of coastal landscapes. [4]

Answer 15

sub-aerial weathering involves the action of rainwater and insolation on coastal landforms.
material is broken down in situ which can cause large scale mass movement of rocks.
biological weathering is when animals grow/ build nests in the cracks of the cliff/ rock causing them to become bigger and then eventually weakening and enlarging the cliff.
chemical weathering occurs when precipitation mixes with the minerals in the rock, eroding it and causing it to weaken.
mechanical weathering occurs when water gets into the cracks of rocks, the water will then freeze and expand, causing it to expand and weaken the rock. this happens repeatedly making pronounced cracks in the rocks strata.

Question 16

Explain the difference between eustatic, isostatic and tectonic sea level change. [4]

Answer 16

Eustatic sea level change is global scale sea level change, which usually happens when there is a change in the earths atmospheric temp. this causes glaciers to melt, which increases the amount of water in the ocean. Alternatively, cooler temps can cause water to freeze, which reduces the amount in the ocean. it can also occur when there is a thermal expansion of water.
isostatic sea level change is a more local scale change in sea levels. it occurs when ice sheets melt, causing the land to rebound and making the sea levels lower in comparison to the land. this causes immigrant features.
Tectonic sea level change occurs when tectonics create new land which displaces the amount of water able to fit in the ocean.

Question 17

Explain the concept of the sediment cell. [4 marks]

Answer 17

sediment cells are closed systems, that are bounded by headlands. Within a sediment cell erosion, transportation and deposition all occur within a long term cycle.
there is little to no movement between cells. The only inputs are from erosion of the sea bed or land. human activities such as beach management can interrupt these processes, which can put certain areas of the beach at risk of being eroded.

Question 18

Outline characteristics of constructive waves. [4 marks]

Answer 18

• they are associated with a flat beach profile, but they build it up due to the strong swash and weak backwash.
• the wave period is 8-10 seconds
• low surging long wavelength
• they are formed by distant weather systems.
• they have longer wave lengths than destructive

Question 19

Outline characteristics of high energy coasts. [4 marks]

Answer 19

• Erosion occurs more than deposition
• They are more likely to experience
  tropical storms
• they have a larger fetch
• they are likely to be exposed to strong
  prevailing winds, which creates
  destructive or high energy waves.

Question 20

west wittering case study

Answer 20

• depositional environment, low energy, sediment moved along the spit from south to north by longshore drift.
• East head spit has been formed due to the longshore drift.
  a ria has formed where a river has been submerged by rising sea levels.
  brackish water has been created where sea and river water meet and mix.
  behind east head spit there is a salt marsh that is being protected by the sand dunes and spit.
• steak holders include Natural England, The environmental agency, Chichester district council, national trust, local residents, and visitors of the area.
  -during the 80s & 90s there was severe erosion to the west sea facing side of the spit, and in 2005 a ‘rock berm’ was installed inside the barrow hinge area to try and secure the spit. in summer of 2005 & 2009 a large quantity of sediment was deposited from the northern tip to produce a bank over the top of the rock berm, and marram grass was planted on top.
• the management plan for this area is adaptive management, which is a form of managed realignment but is reviewed frequently and action taken out to protect the hinge. This management plan will try and monitor the spit but not lock it into its current size, shape or orientation.
• wooden groynes have been places along WW beach but east head spit is protected by soft engineering. the wooden groynes are not being replaced, as the aim is to create a sloping beach that can better absorb wave enegry and also retain access to East head.

Question 21

Bognor Regis case

Answer 21

• beach faces a SSE direction and sediment is transported from West to East.

Question 21

Pevensey bay

Question 22

answers to questions https://www.tutorhunt.com/resource/26461/#:~:text=A%20barrier%20beach%20is%20usually,barrier%20beach%20forms%20(1)

Question 23

Sundarbans case study