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Geography- Global Systems and Governance > Antarctica > Flashcards

Flashcards in Antarctica Deck (63)
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1

Antarctica is the driest continent because...

Its' annual precipitation is 50mm- polar desert

2

Antarctica is the windiest continent because...

Smooth Antarctic surface allows for fast winds not slowed by surface friction

3

Antarctica is the coldest continent because...

Average temperature is -49oc (feels colder due to wind chill)

4

Ablation

Opposite of accumulation
Processes that remove snow, ice, and water from a glacier or snowfield
(i.e. evaporation, melting of snow, ice running off a glacier, removal of snow by wind)

5

Nunatak

An exposed, often rock element of ridge, mountain or peak not covered with ice or snow within (or at the edge of) an ice field or glacier

6

Antarctic Convergence Zone

A natural boundary separating 2 distinct hydrological regions, areas of distinct climate, areas of distinct wildlife

7

Why does the Antarctic Convergence Zone vary seasonally?

Due to the expansion and contraction of sea ice

8

Thermohaline Circulation

Salt water moving along gradients creates the global thermohaline circulation
Water moves from hot to cold (convection)
Changes in salinity accelerate these changes

9

2 main factors that have increased the threat Antarctica faces

Technology- we can now get there
Greater demand for resources- exploiting Antarctica is now economically viable

10

What are the 4 main threats Antarctica faces?

Climate Change
Fishing and Whaling
Mineral Exploitation
Tourism and Scientific Research

11

Climate Change: Which parts of Antarctica are cooling?
Which parts aren't?

East cooling- not near the coastal parts (ocean a radiator)
West melting- likely the East will grow as the West melts

12

Climate Change: What is the melting of the Antarctic Peninsula causing?

Positive dieback- loss of ice shelves has caused ice to speed up in land

13

Climate Change: How many tonnes of ice have been lost each year since 1993?
By how much have global sea levels increased as a result?

100 billion tonnes each year
Increased global sea levels by 0.2mm a year

14

Climate Change: What will partly offset the increase in the rate of ice melt?

Increased snow fall

15

Climate Change: By how much has Southern Ocean temperatures increased since 1995?

1oc

16

Climate Change: What impacts has the Southern Ocean warming more quickly that the oceans globally had?

Changed distribution of penguin colonies
Krill populations fallen by up to 80% in last 40 years
Melting snow = increased plant colonisation
Ocean acidification

17

Climate Change: Although the melting of ice shelves doesn't contribute to sea level rise, how do they cause it?

Rate of flow of glaciers behind the ice shelves increases
These glaciers melt = sea level rise

18

Climate Change: Why might sea ice be expanding on the eastern side of Antarctica?

More snow and rain layering Southern Ocean with a cooler, denser top
More storms = local waters less salty, raises temp. of ice formation
Melting of continental land ice = icebergs- contributes to sea ice formation

19

Climate Change: What is the problem with the carbonic acid that would be created with increased atmospheric carbon dioxide?

Oceans would become a little more acidic
Could potentially corrode unprotected shells and skeletons- problems with food chain

20

Climate Change: Why would some argue global trade/ globalisation was responsible for climate change?

Global trade has increased movement of goods- increased fossil fuel consumption
(Antarctica doesn't benefit from this trade at all, it is instead impacted by the pollution and waste generated from the trade)

21

Fishing and Whaling: Why are krill so heavily fished around Antarctica?

Fishing restrictions implemented in Northern Hemisphere
2007, catch allowance increased by nearly 600%

22

Fishing and Whaling: Problems with over fishing of krill?

Impacts food chain
Increases phytoplankton

23

Fishing and Whaling: When did whaling begin in this area?

1904

24

Fishing and Whaling: Where was the whale processing station located?

South Georgia

25

Fishing and Whaling: When was commercial whaling banned?

1986

26

Mineral Exploitation: Where is there a large amount of coal?

On the coast and in the mountains

27

Mineral Exploitation: How many barrels of oil do the Ross and Weddell Seas combined hold?

50 billion barrels of oil

28

Mineral Exploitation: Demand for minerals could cause global ____ in the future

Conflict
Many countries already put in claims as safeguard measures

29

Tourism and Scientific Research: How many permanent scientific bases are there?

40
Means resources have to be flown or shipped in

30

Tourism and Scientific Research: What happened with the Argentine navy transport ship in the late 20th century?

It ran aground
Released 250,000 gallons of fuel
Sea birds and krill were killed
(This was a relatively contained oil spill)