Climate and Living
Personnel returning from the Antarctic are often asked how they enjoyed, or endured, the cold. The answer to this lies in alpine New Zealand where mountaineers or high-country shepherds often experience temperatures equivalent to those of the Scott Base summer, which fluctuate around freezing point (32°F). This is much milder than a northern United States winter. Summer, then, presents little problem to the adequately clad. In the infrequent windless conditions, it is possible to work out of doors in a woollen jersey, shirt, underclothes and tweed trousers–the form of dress affected by outside workers in New Zealand–except that multi-layered fabric boots (mukluks) are used when standing or walking in snow. For severe Antarctic conditions, the worker wears the anorak (parka with fur-lined hood) and trousers of synthetic material, often nylon, light, little-insulating, but windproof. Warmth of the body is controlled by the retention of bodily warmed air in the clothing, so that a slight breeze (2–3 m.p.h.) immediately cools one unless “windproofs” are donned to prevent the loss of warm air next to the body. Cold is rendered many times more intense with each mile per hour of wind speed. A still air temperature of, say, 20°F (12 degrees of frost) is much more comfortable than conditions at 32°F in, say, a 30-knot breeze. Wind, not the air temperature, is to be feared.
Lack of discomfort in cold is partly due to the extremely low humidity of the atmosphere. In Antarctica biting cold is absent because of this. So dry is the air that wet clothing, even though frozen, dries readily. Ice melts more by sublimation (the direct change from solid water to water vapour without the liquid stage), so that ice melt-streams are rare even near the bare rock “oases” of Victoria Land. Snow patches on rocky surfaces disappear with only a slight dampness temporarily to mark their previous existence. Wood is so dry that it readily breaks or shatters, and fire is a hazard in the tinder-dry atmosphere where the only water available is solid ice or snow.
The preservation of huts and stores, and seal or dog carcasses is remarkable as the huts of Scott and Shackleton testify. Tins of food lying outside for half a century are little rusted and, if they have been sheltered from the abrading gales, their labels are faded but readable. This land is drier than the deserts of Australia, Africa, or America.
In winter, Scott Base and Pole Station experience marked subzero temperature, –30°F and –80°F respectively which, with frequent gales or blizzards of 100 knots or more, and the winter darkness, limit outside activity. Moonlight and occasional windless conditions, however, allow the “wintering-over” personnel to move around the base and repair any damage to huts and radio aerials by wind and drift. At Scott Base the dogs are tethered outside on the nearby sea ice throughout the winter.
One result of the Antarctic low atmospheric humidity is the low precipitation. At Scott Base it is equivalent to a rainfall of but 6–7 in. At Pole Station it is only half this. This is less than that of the world's hot deserts. On the Ross Ice Shelf, accumulation is at the rate of approximately 8 in. per annum, but such scanty falls as this are sufficient to maintain the ice plateau as a 2-mile deep cap over the bulk of the continent.