Global Systems & Governance - Contemporary Geography of Antarctica Flashcards
What is the climate of Antarctica like?
- The coldest, driest and windiest of all the Earth’s continents
- Highest average elevation of all continents
- Annual precipitation of only 200mm (classified as a desert)
- During winter, monthly mean temperatures at coastal stations are between -10C and -30C.
- Several metres of snowfall each year
- Mean wind speeds can exceed 30m/s
What is the annual precipitation of Antarctica?
200mm
What are the mean winter temperatures of Antarctica?
Between -10C and -30C
What are the mean wind speeds in Antarctica?
30m/s
What is the topography of Antarctica like?
Mountainous and rocky terrain
How much of Antarctica is covered by glacial ice?
97%
What is the highest peak in Antarctica?
Highest peak is in the Ellsworth Mountains - Mount Vinson
What is the average height of Antarctica?
Average height of 2300m above sea level
What is the most active volcano in Antarctica?
Mount Erubus is the most active volcano (hotspot)
Southern Ocean
- In 2000, the Southern Sea was delimited (boundaries became fixed)
- Comprises the southernmost waters of the world, south of 60S latitude
- Circumpolar body of water, encircling Antarctica
- The mixing and upwelling of currents create krill in large amounts
What is the Antarctic Circumpolar Current (ACC)?
An ocean current that flows clockwise from west to east around Antarctica. It is the largest ocean current in the world as is driven by wind. It is the only current linking all of the major oceans – Atlantic, Indian & Pacific
Why is the Antarctic Circumpolar Current (ACC) so important?
- Moves west to east around Antarctica
- Moves water northward, creating a pressure gradient
- Ekman Spiral forms in the east
- Coriolis effect causes pressure gradient, pushing north, leading to upwelling
- Allows the Southern Ocean to be exposed to the atmosphere and exchange gases and heat
- Blocks warmer water travelling southwards (towards Antarctica)
What is the Antarctic Convergence (AAC)?
The Antarctic Convergence is a boundary line that separates the Antarctic and subantarctic regions. It is a curved line that fully encircles Antarctica, and which varies in latitude seasonally. It is the point where the cold Antarctic water meet, mingle and sink beneath warmer subantarctic waters. The line is also referred to as the Antarctic polar front. When the two water regions meet, nutrients situated in the seafloor are carried to the surface, rendering the convergence zone suitable for the growth of microorganisms such as phytoplankton and creatures like krill. These life-forms contribute to the food chain of the region’s residents, including seals, penguins, whales, albatrosses, and fish. The zone is among the southern hemisphere’s primary marine food sources.
Vulnerability to global economic pressures and environmental change
The threats to Antarctica may disturb its fragile environment and will impact on indigenous species and biodiversity. The Scientific Committee on Antarctic Research (SCAR) monitors the resilience and adaptation to these disturbances and effect of any mitigation put in place.
