1958年7月亚洲东南部西南季风区和太平洋信风区平均流场和平均经圈环流

亚洲东南部西南季风区和太平洋信风区环流特点有显著的不同。在季风区有南部下沉、北部高原地区上升的垂直季风环流,高层有东风急流,下层有达400毫巴高度的深厚的西南气流。在信风区、低纬度则存在着典型的Hadley环流,高层有夏季太平洋中部副热带西风急流,下部有东北信风,东风随高度减弱。 季风垂直环流的存在,进一步说明了季风形成的因子。

A COMPARISON OF MEAN WIND FIELD AND MEAN MERIDIONAL CIRCULATION BETWEEN SOUTH-WEST MONSOON AREA IN SOUTH-EAST ASIA AND PACIFIC TRADE WIND AREA IN JULY, 1958

The existence of the monsoon vertical circulation cell, as shown in fig. 8, which consists of an ascending current near and over the Tibetan plateau and a descending current on the south, is directly proved by calculations from the actual wind data in July 1958. In the same period, the meridional circulation is} a typical Hadley cell in the Pacific trade wind area (fig.9). In S-W monsoon area, there exists the easterly jet in the upper troposphere and the south westerlies in the lower, but in the Pacific trade wind area, there is a westerly jet near 200 mb level and the easterlies in the lower troposphere. The factors which cause the monsoon circulation are discussed.