Global Governance - Antarctica Flashcards
What is most of continents coastline fringed by
Ice shelves
Example of ice shelf in Antarctica
Ross ice shelf in the Ross sea- covers more than the British Isles
What is the Antarctic Convergence
A curve continuously encircling Antarctica where cold northward flowing Antarctica waters meet the relatively warmer waters of the sub-Antarctic
How wide is the Antarctic Convergence
32 to 48 km wide
What does the Antarctic Convergence separate
- 2 distinct hydrological regions
- areas of distinct climate
- areas of distinctive wild life
What does the warmer and colder waters meeting create
A highly productive marine environment for plantlife and animals e.g. krill due to the mixing and upwelling currents
What happens at the Antarctic Convergence
Warm, more saline waters coming south from the tropics meet the cold, denser and mainly non-saline waters moving north from the Antarctic.
What is the Antarctic Circumpolar Current
The largest surface current in the world which flows around Antarctica, blocking warmer waters travelling southwards
What percentage is Antarctica covered by ice
97%
What divides the continent into East Antarctica and West Antarctica
The Transantarctic Mountains
What is the average temp in Antarctica
-49 degrees
What’s the mean annual wind speed
50 moth
What is the mean annual precipitation
Less than 50 mm, can be described as a polar desert
What are the thick ice sheets a result of
Accumulation of small inputs of snow and frost over a very long period of time
What type of climate do some coastal areas have
Micro climate and topographic conditions which cause enough melting during summer months to allow some land to remain free of glaciers
What are the 4 threats to Antarctica
Fishing and whaling
Climate change
Search for mineral resources
Tourism and scientific research
When did exploitation of marine life start
Antarcticas discovery in 18th century led to economic activities e.g. fishing, whaling, seating
What is beneath the ice of West Antarctica
An archipelago of steep mountainous islands
Why is the environment extremely fragile
It’s east to disrupt any part of it with knock on effects
Environmental recovery is slow - e.g. footprints on moss can remain for decades
How low have dry valleys not had precipitation for
Over 2 million years
When were fur seals of South Georgia wiped out
By 1800 and 3 years later virtually eradicated from South Shetland islands
When did whaling have a more deviating effect
19th century
What 3 nationalities exploited blue and white whales in 19th century
Norwegian, British and American
What were whales exploited for
In 19th century oil and baleen
In 20th century meat extract and frozen whale meat