Coasts EQ3 (2B.3)

Question 1

what is the worlds lowest lying country ?

Answer 1

the Maldives which is just 1.4 metres above sea level

Question 2

what are the 2 main factors causing sea level rising ?

Answer 2

1. Ice caps and glaciers melting

2. thermal expansion- water expanding as it heats up

Question 3

what have Kiribati done to save its population from rising sea levels ?

Answer 3

They have purchased an island in Fiji to move its population to and use it for agriculture. Also the government have launched a policy to make it easy for people to apply to neighbouring countries such as new Zealand.

Question 4

what is isostatic and eustatic change ?

Answer 4

isostatic= when the land rises or falls relative to the sea 
eustatic= when the sea level itself rises or falls

Question 5

what are some examples of eustatic changes ?

Answer 5

sea level falls due to water being stored in ice caps and it rises when the ice caps melt and thermal expansion occurs

Question 6

what are some examples of isostatic change ?

Answer 6

sea level falls due to the colossal weight of land based glaciers causing the land to sag. When the glacier melts the ground rebounds up slowly. Sea level can rise when deposited sediment on the coast causes the land to sink.

Question 7

What other factors have enhanced sea level rise ?

Answer 7

• Tsunamis which can cause permanent flooding for example the the boxing day in Indonesia
• greenhouse gasses and climate change

Question 8

what are emergent coasts ?

Answer 8

They are the result of isostatic and eustatic changes happening at different rates. The land rises slowly out of the sea leaving landforms reflecting previous sea levels.

Question 9

what are the different emergent landforms ?

Answer 9

raised beaches-as the land rose due to isostatic recovery the features of previous sea levels such as shoreline platforms and beaches rose above sea level for example west Scotland

fossil cliffs- lines and wave cut shapes can be found as evidence of past erosion for example the isle of Arran

Question 10

What are submergent coastlines ?

Answer 10

coastlines that are a result of sea level rise or isostatic sinking

Question 11

what are the different submergent landforms ?

Answer 11

a Ria- when valleys are flooded after sea level rise for example in Devon

a Fjord- similar to a Ria but are glacial and very deep and steep sided. They are inland with a small opening where the glacier previously opened into the sea

Dalmatian coasts- parallel hilly islands that have been submerged to create elongated bays

Question 12

how has sea level changed since 1800 ?

Answer 12

• It was stable between 1800 and 1870
• has risen slowly since 1870-1950
• since 1940 it has risen very fast

Question 13

why is It difficult to predict sea level rise ?

Answer 13

there are so many factors that can effect it such as glacial melting, thermal expansion and climate change

Question 14

what are some human processes that effect erosion ?

Answer 14

• coastal defenses as defenses at one part in a coastal cell have a knock on effect for the rest of the cell
• dredging as it makes the channels deeper
• dams as they starve the coat of sediment

Question 15

what features do rapidly eroding coasts tend to have ?

Answer 15

• long fetch
• soft geology
• weak structural cliffs
• strong long shore drift
• large destructive waves

Question 16

what are the causes of rapid erosion at Holderness ?

Answer 16

• the coast’s geology is weak as it features boulder clay
• the coast is exposed to strong waves and a long fetch form the north sea
• the sea floor is deep so the waves aren’t slowed down much making them more destructive
• sediment is transported away from the area due to long shore drift laving it unprotected
• mass movement such as lumping occurs on the clay cliffs

Question 17

what are the impacts of erosion at Holderness ?

Answer 17

• no compensation for those that have lost property or land
• people have lost their source of income such as caravan parks or farms
• freshwater marches, lagoons and dunes and wetlands are at risk

Question 18

what have been the Reponses to rapid erosion at Holderness ?

Answer 18

• the Yorkshire council have spent £1.2 million to help those suffering
• there are websites and companies that can help pay for and advise the residents on relocating inland

Question 19

what are some processes that increase the risk of coastal flooding ?

Answer 19

• storm surges and tropical cyclones flood deltas more quickly
• destruction of mangroves exposes the coast more
• river straightening means the water flows quicker and sediment is propelled further off shore
• groundwater extraction accelerates ground subduction

Question 20

why have storm surges impacts increased in Bangladesh ?

Answer 20

• firstly there has been a large decrease of mangrove which would normally protect the coast. This is because of rising sea levels and human removing it.
• Secondly the subsidence of land due to large embankments being built which stopped the islands from getting sediment to maintain its height.
• Bangladesh is one of the poorest and most densely populated cities in the world so the effects of the storm surges are devastating