Desarrollo de la Antártica

Takesi Nagata / THE ADVANCEMENT OF SCIENTIFIC RESEARCH ••• • researoh station, are performing trheir routine meteowlogical observa– tions. Those stations which have asterisks in the meteoTology column in Table 2 are carring out the upper air observations by means oE radioBo,ndes in addition W the surface meteorological observations. Fig. shows the distribution oE 20 meteorological observatories where both the surafce and upper-air meteorological observations are being carried out in 1975. b) Climate 0'1' Antarctica The Antarctic clima te is strongly characterized with the very strong albedo by the wihite snow surface in addition to the less amount oE solar radiatíon. It hás been clarified, for example, that only 11 % oE the short-'lvave solar radiation can be absorbed into the ice-sheet at a level oI 3000 m in the central part of Antarctica. The heat balance with respect to the infra-red radiation Ilhere, on the other hand, amounts to 12'1 % oI the n,et loss from the ice-sheet surface. Namely, the total heat balance at the central Antarctic is represented by 10% oI the net heat losB. These conditions result in the Antarctic climate to be the coldest in the world. Thus, the annual mean temperature amounts to -55°e at the highest inland area and to -15~C along the coastal line of Antarctica. The annual change in temperature in the Antarctic inland is sub– jected toa particular mode, which is characterized by a sharp de– crease around March and a sharp increase around October. This U shape mode of annual temperature change is specifically called "the coreless winter in Antarctica". The Antarctic climate is characterized also by Erequent H'katabatic" wind'i, "WIhich blow down along a sharp downward slope near the ice-sheet outer edge. This strong and sud– den katabatic wind was first found by M'awson in 1915. According to his report, the maximum wind velocity amounted to 100 m/sec. Dalrym1e (1966) summarized the ulntarctic plateau climate by tao king into consideration mostly temperature, wind and sorne other meteorological elements, where the Antarctic plateau was defined as the higland areas aboye 2000 m in East Antarctica and above 1500 m in West Antarctica. IGeneraIly, the air temperature over the IAntarctic plateau never excedes ooe, and the average temperature, the average snow accumulation rate and the average atmosphere coolíng rate are less than -17.8°e, less úhan 450 mm water/year, and more tlhan 1800 k. ca1/m 2 /hour respectively. In East Antarctica, climate corrditions are classified into three zones from the highest plateau area· towards the sea coasts. 77