//4.c. Climate change is altering high latitude oceans

Question 1

Why does sea water freeze in the high latitude oceans

Answer 1

• high latitude oceans are the Arctic and the Southern Ocean around Antarctica
• sea water freezes in these oceans at -2°C because of the salt content
• there is very little heat input into the heat budget system as the sun’s angle is low and heat energy is spread over a large area and large amounts of incoming solar radiation are reflected

Question 2

How does global warming impact the sea ice area

Answer 2

• between 1978 and 1996, the area of Arctic sea ice decreased by 2.9%
• in 2015, ice covered 4.0 million km² compared with a long term average of 15.0 million km²

Question 3

How does global warming impact the thickness of ice

Answer 3

• in 1960s, Arctic sea ice averages 4m thick at the centre, whereas it is now about 1.25m thick
• main concern is that as sea ice reduces in extent, more solar radiation will be absorbed by the sea and not reflected, leading to further sea warming and more melting of sea ice

Question 4

Case study- implications of melting sea ice in the Artic- indigenous people

Answer 4

• these people hunt and fish in the Arctic ocean
• their sustainable harvests of animals e.g. seals are affected by the patterns of sea ice and weather
• disruptions to the ecosystem make hunting less reliable and more dangerous

Question 5

Case study- implications of melting sea ice in the Artic- transport

Answer 5

• shipping across the Arctic is connected to mineral exploitation
• sea ice has made the Arctic Ocean impassable to shipping
• explorers have tried to find and sail through the North West Passage from Northwest Atlantic to Pacific Ocean
• interest in the Northern Sea Route is growing as companies could reduce their costs signficiantly by using either of these routes but costs rise e.g. high fuel consumption of vessels sailing through sea ice

Question 6

Case study- implications of melting sea ice in the Artic- minerals

Answer 6

• as warming melts sea ice and the tundra, exploration is revealing vast reserves
• global transnational corporations in the energy and mining industries are taking the prospect of recovering vast reserves seriously

Question 7

Case study- implications of melting sea ice in the Artic- geopolitics

Answer 7

• tensions between completing powers have been increasing for some time
• claims over vast areas of the Arctic ocean have been lodged by Russia, Canada and Denmark
• a country must prove the sea bed is an extension of its continental shelf

Question 8

Case study- implications of melting sea ice in the Artic- management

Answer 8

• the Arctic Council is acquiring a substantial role in governing the region
• the diversity of indigenous people is representated in the council
• an indiciation of the growing international interest in the Arctic is the 12 observer states- includes UK, hina and Singapore