Snowstorm
          Antarctica is the coldest continent on earth, in the central plateau there are temperatures between –50°C and –60°C. In Antarctica is the annual number of daylight hours similar to equatorial latitudes, even the sun doesn’t shine for half of the year. But the short-waves from the sun strike the Poles at a oblique angle, the rest of the waves is either absorbed by gases in the atmosphere or reflected into space by clouds and by the snow and ice cover. As a result, the continent loses more solar energy than it receives during the year. Only for a short time at midsummer is there a net energy gain. Of course the Arctic has the same conditions, but the Arctic is surrounded by continents and Antarctica by the ocean. The belt of westerly winds sweeping round the Southern Ocean isolates Antarctica from the rest of the world and reduces the energy transfer. But the coldest place is not the South Pole, because at 2800m it is not the highest. Vostok at 78°S and 3500m has recorded the lowest temperature on earth with –89.6°C on 21 July 1983.

          Antarctica is not only the coldest continent on earth but also the windiest. Because it is so cold at the ice surface, the air gets warmer with height, instead of colder. This means that on a slope, the air close to the surface is colder and denser than air at the same altitude above a point further down the slope. So this coldest, densest surface layer flows down the slope under gravity, creating a katabatic wind effect.

Dry-valleys

Aurora