global gov (3.2.1.5) Antartica Flashcards
where is most of Antartica?
south of the antarctic circle
what are the 2 largest ice shelves that that fringe the coastline?
Ross ice shelf (ROSS SEA)
Ronnie ice shelf (WEDDELL SEA)
how big in the antarctic convergence zone?
32-48km wide (varies in latitude seasonally)
what happens at the ACZ?
cold, northward flowing Antarctic waters SINK beneath the warms south flowing water. the forms associated areas with upwelling and mixing= high marine productivity especially in antarctic krill
what does the ACZ separate? 3
- two distinct hydrological regions
- areas of distinct climate
- areas of distinctive wildlife
what % of Antartica is glacial ice?
97.6%
what is the transantartic range?
area that contains 4000m and divides west and east Antarctic ice sheets
what is the difference between the east and west ice sheets?
EAST
-larger/ thicker
WEST
-smaller/ thiner/ older
What is the average hight of antarctica above sea level?
2300m above sea level (known as the highest continent)
what is the average temperature of Antartica? what is the lowest?
- 49°C
- 89°C
what is the average wind speed and the result of this?
50mph result from the convergent katabatic winds
what is the highs that the wind speed can reach?
200mph
what is the mean annual precipitation?
less than 50 mm yearly
what is best word to describe the climate of Antartica?
polar desert
what does the blooming of phytoplankton lead to?
food for krill
what are the 5 main threats to Antartica?
climate change, tourism, scientific research, mining and fishing and whaling
when did fishing and whaling begin?
19th century
who where the targets of fishing and whaling?
blue and right Wales for oil and whale bone
what is the main effect of fishing and whaling?
species extinction
give an example of a close species extinction?
1830’s antarctic fur whale
how many blue whale are left?
10-25,000 (3%-11% of 1911 figure)
what has happened to the % of krill since 1970s?
dropped by 80%
what happened with the minke Wales ?
in 2018 Japanese whale hunters where in Antarctica’s waters and killed 333 whales of which 122 were pregnant , claimed it was part of a scientific research investigation
who are The Antarctic treaty (1959)?
give rules on how antartica should be sustainably managed
who are the ‘protocol an environment protection of antarctic treaty’ (1991) ?
-protects the environment
who are the IWC (1946)?
international whaling commission, responsible for regulating whaling and declared a pause on commercial whaling in 1982 (Japan found loop hole)
