东亚对流层上部和平流层中下部大气环流的初步研究

A PRELIMINARY STUDY ON THE GENERAL CIRCULATION OF EAST ASIA IN THE UPPER TROPOSPHERE AND STRATOSPHERE

中文摘要:

      根据1957-1961平东亚九十余个探空站的记录,对东亚对流层中上部和平流层中下部的大气环流特点作了初步的分析,得到如下几点结果:1.在冬季,对流层中上部的气压场和风场特点和过去研究的结论基本一致。在夏季,高原部分的环流特征却和过去的结论不同,夏季在高原上对流层中部出现微弱的气旋性环流,但在300毫巴已在反气旋的控制之下,而且反气旋的势力愈往上去愈强,在100毫巴处高原上空的反气旋达到最大强度,这是与青藏高原的热力性质有关系的。此外,从1月到7月东亚对流层上部的气压场和风场变化甚大,在中高纬度气压场有相反的趋势,并且副热带高压脊线从冬季的北纬15°位置移到夏季的北纬28°2.在东亚沿海,中纬度的几个测站在平流层中部的温度年变程呈双峰型,最高温度出现在1月和6-7月。在低纬度温度的年变程也呈双峰,但位相与中纬度相反。低纬温度年变化特点与辐射有关;中纬度的温度年变化,经过计算表明,1月的高峰与温度平流有密切关系。3.东亚对流层中上部和平流层中下部风场的季节变化,与对流层中下部一样显著。从夏到冬的环流季节变化过程,高低空有一致性,而从冬到夏的环流季节变化过程,高低空变化并不一致。

英文摘要:

      Based on the aerological data in the years 1957-1961 of more than 90 stations over East Asia,the monthly mean circulation from 500 mb to 10 mb level is discussed.The main results obtained are as follows:1.In winter,the major features of the circulation in upper troposphere and stratosphere are roughly in agreement with the previous conclusions.But in summer,it differs from the earlier conclusions,in that,there is a weak ryclonic circulation over the Tibetan Plateau at 500 mb.However,it becomes anticyclonic at the 300mb level and intensifies with height up to 100 mb level.Furthermore,the distribution of major troughs and ridges in the middle latitudes are reversed from January to July.2.Above the 30mb level,the annual variation of the mean monthly temperature appears to have two peaks is a year at some stations situated from 37°N to 45°N.The causes are discussed.3.The seasonal reversal of wind field from the upper troposphere to the stratosphere is as pronounced as in the middle and lower troposphere.The process of the revernal in the upper atmosphere in fall is associated with that in the lower atmosphere,but the reversals in spring in the troposphere and the stratosphere seem to be unrelated with each other.