Why Antarctica is Cold

Some interesting information:

The Russian base at Vostok (78.5° S, 106.9° E), which is 3488 m above sea level, is the coldest place on earth with a mean annual temperature of around –55° C. The coldest recorded temperature at Vostok was –91° C in 1997. This is far colder than dry ice, which has a temperature around -70° C. The South Pole (90° S), which is at 2,835 m, has a mean annual temperature of about –49° C.

Cape Denison, the "home of the blizzard" where Douglas Mawson built his hut in 1912 is probably the windiest place on earth. During one spectacular and persistent hurricane Mawson recorded "a terrific series of Herculean gusts..... in the order of 200 mph" (320 km h-1). The highest recorded wind velocity is 327 km h-1 which was measured at the French base of Dumont d’Urville in July 1972.

Why is Antarctica so Cold?
- First, the sun is always relatively low in the sky over Antarctica so its surface receives less energy. On Midsummer's day at the South Pole, for example, the sun is only 23.5° above the horizon and a shaft of sunlight is spread over a much larger area than an equivalent one would be on the equator.

- Second, the sun does not rise at all in regions south of the Antarctic Circle for part of the year. At the latitude of the Antarctic Circle there is one day a year of total light (21 December) and one of total darkness (21 June), whereas at the South Pole, there are 6 months of daylight and 6 months of darkness. On average, Antarctica actually loses more energy by infrared cooling than it gains from the sun.

- Third, the whiteness of the ice sheets and the sea ice (which together can extend over 35 x 106 km2 in the winter) results in the reflection of up to 85% of the incident polar radiation.

- Fourth, Antarctica is the highest continent on earth (average height 2,500 m). Away from the coast, the temperature decreases by about 1° C for every 100 m rise in height.

- Fifth, the Antarctic Circumpolar Current flows completely around Antarctica largely preventing other warmer ocean currents from exerting significant effects.
Finally, Antarctica is an isolated continent without significant neighbouring land masses which can have a warming effect on the climate.

Sweet.

And I have a FOUR HOUR Psych test on Tuesday...