But scientists at the British Antarctic Survey (BAS) and the Arctic and Antarctic Research Institute (AARI) in Russia were able to solve the mystery with a computer model developed to simulate the future evolution of the Antarctic climate, along with weather charts and satellite imagery of the area.
They found that relatively warm air that normally flows over the Southern Ocean onto the high Antarctic plateau almost came to a halt during this period. A flow of cold air circling Vostok was preventing the mixing of this warmer air from lower latitudes, isolating the station and causing near optimum cooling conditions.
Adding to this was the absence of a heat-trapping cloud cover and the presence of a layer of tiny particles of ice suspended in the air (known as diamond dust), allowing more heat from the continent's icy surface to be lost to space.
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