Desarrollo de la Antártica

EL DESARROLLO DE LA Ñ'iTÁRTIU a) Cold central core (annuaJ average temperature T < -50()¡C, the lowest temperature T min < -800: e, the highest temperature T max < -20°C, the average wind speed w 3 '--'" 5 mjsec) , b) Cold interior zone ( -40 '--'" -50°C, T min = -70° '--'" -80° C, T max = -100 '--'" 20°C, w = 5 '--'" 7 mjsec.). c) Cold katabatic zone ( -30° --. -40°C, T min = -55° '-'" 700C, T max = -5° '--'" -200C, w 9 '--'" 12 mjsec.), whereas the higland area in West Antarctica is occupied by Cold Transitio- nal Zone (T - -250 '-'" -400C, T min 50° -70°C, T max O '-' looC, w = 7 '--'" 10 mjsec.) . c) The air clrculation in the Antarctic 1'egion The large negative value of radiative heat balance over hlle Antarctic plateau must be compensated by the horizontal transportation of warmer air-mass and the water vapour from the northern tempera te zones. Compared with the Arctic condition where both the atmosphere and t'he ocean current can transpon the heat in, he Antarctic condi– tion permits only the air-mass to compensate the large iheat loss in Antarctica. This particular condition in nature inevitably results in a stronger and grater-in scale circulatíon of the atmosphere in die Antarctic region in comparison with the Arctic. In general, hlle circumpolar vortex around the pressure low center over the Antarctic plateau controls the weather in Antarctica &nd its vicinity. For example, all local cyelones (the pressure low centen) move from the west to óhe east and a littIe bit polewards, but they can very seldom get into the inside continental area. The upper air structure over tihe Antarctic continent is remarkably particular in comparison with that in oÍ'her regions. The particularity may be re– presented :by the following three characteristic phenomena, namely, i. The tropopose (the boundary between the troposphere and the stratosphere) becomes higher in winter than in summer. ii. The tropopose tends to become indefinite in winter. iii. The range of annual temperature variation of the strat05phere i5 unusually large ( > t40°C) and the temperature rapidly in– creases in spring. These anomalous phenomena have been interpreted as due OTigi– nally to the anomalously large albedo of the ice surface of Antarctic plateau, which causes, for example, a steady inversion layer from the 80