"Below 60°S latitude lies the immense white continent of Antarctica. In the geography and history of the world, the Antarctic is like no other land: it is the coldest, highest, driest and most inhospitable continent on Earth. Antarctic rocks span a period greater than 3 billion years. Antarctica receives the greatest amount of solar radiation of any part of the world during summer due to having 24-hour daylight and the effect of perihelion, (the earth is at its closest elliptical orbit to the sun.) The atmospheric mositure of Antarctica is 10,000 times less than at the equator. Ice is formed at the rate of 30 square miles per minute and in the space of a few months, it extends to 7 million square miles, effectively doubling the size of Antarctica. Icebergs can be as large as small countries. Masses of ice the size of a small house are known as 'bergy bits' whilst those the size of a care are called 'growlers.' During the formation of glacial ice, bubbles of gas become trapped within it and these are released as the ice melts. When a pocket is exposed, the gas escapes with a fizzing sound, a phenomenon that is termed 'bergy seltzer.' Antarctica receives very little annual precipitation, equivalent to a few millimetres of rain, giving it the official classification of a desert. Only about two percent of Antarctica's 14 million square kilometres is free of ice. In this area, approximately 85 species of moss, 25 liverworts, 150 lichens and both vascular plants have been reported."
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