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Apart from being the coldest continent, Antarctica has the strongest winds in the world.
Ice flow off Dundee Island - HMS Endurance
In Antarctica, Katabatic winds (Katabatic means `down-flowing') are created by the cooling of air close to the surface of the ice sheet on the higher parts of the continent. As this cold heavy air sinks, it presses down hard, pushing away all the air that was underneath. This process creates a downhill wind which, by the time it reaches the coast, is blowing very strongly. Katabatic winds have been recorded at over 300 km per hour and for the early explorers to Antarctica, were as big a problem as the cold as they often became hopelessly lost in the blizzards created by the winds.
Another problem in Antarctica created by the winds, is wind chill. Wind chill factor measures the combined effect of the low temperature and wind. This can cause body heat to be removed faster than a body can replace it. When the heat loss is high, body tissue can freeze, a condition known as frostbite. When wind-blown snow makes contact with warm skin (blood temperature 37ºC), some of the snow melts, wetting the skin. As the wind causes the moisture to evaporate, heat is extracted. Wet skin loses heat at 24 times the rate of dry skin, so this situation is extremely dangerous. To give you an example of the effects of wind chill, if the wind was blowing at 10 km/h and the temperature was -10ºC, a person could lose as much heat as a person in calm air of -70ºC.
So what do Antarctic winds have to do with climate change? Although you can't see a boundary, the Southern Ocean is made up of the most southerly reaches of the Atlantic, Pacific and Indian oceans, as well as the water that surrounds Antarctica. Winds from Antarctica push the cold surface waters from around Antarctic north, where they meet the south flowing warmer waters of the Atlantic, Pacific and Indian oceans. The boundary where they meet is known as the Antarctic Convergence , which marks the northern boundary of the Southern Ocean, and it lies approximately 2,000 km off the coast of Antarctica.
Eroded icebergs - Steve Canipe
Where the ocean currents meet, the warmer water turns east, driven by westerly winds. The cold water sinks below the warm water and some of it carries on moving north at the bottom of the ocean. This process represents part of a global system of winds and ocean currents that help to transfer heat around the globe and regulate temperatures. Without these movements, the polar regions would be colder and the equator would be hotter.
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Amazing Antarctica