1958—1986年中国对流层和平流层低层的温度变化
TEMPERATURE CHANGES IN THE TROPOSPHERE AND LOW STRATOSPHERE OVER CHINA, 1958-1986
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摘要: 北半球地面平均温度变化的总趋势是,1940年左右增暖达到了峰值,继之变冷直到60年代中期,此后从1970年左右又转入了一个新的增暖期1-3。50年代至70年代北半球自由大气,特别是对流层下半部,温度变化趋势大体与地面温度变化趋势一致4-7。由于一些作者使用的是格点资料,对精度有一定的影响,因此各个结果之间有相当差异8。J.K.Angell和J.Korshover9-101975年以来直接使用探空站资料研究全球各纬带自由大气的温度变化,其近期的研究结果指出11-12,1958年开始的地面和对流层的十年降温已为此后的升温所抵消,1981年的温度已超过了1958—1959年;1960—1985年北半球对流层和地面温度变化的总趋势是增暖的,对流层顶和平流层低层则是变冷的。中国区域内自由大气和地面温度变化如何?本文在这方面作了探讨,发现了一些有意义的结果。Abstract: The data of 25 radiosonde stations in China has been used to estimate mean-annual and mean-seasonal temperature changes of the earth surface, troposphere and low stratosphere. It has been found that mean-annual temperature has mainly increased in low strotosphere, and has decreased in troposphere over most areas of China with maximum cooling area beginning in Qingzang Plateau, passing through North China and ending in Northeast China. The surface warming and cooling areas have showed a col pattern with warming regions in west and east and cooling regions in south and north over China. If boundary is ordered at 35°N, the Northern China has warmed on surface and the Southern China temperature change has been small. Therefore, surface warming has been found in the whole China as in the-Northern Hemisphere. During the period of 1975-1986, the maximum warming was in North China, and cooling:become strong in other regions. Troposphere cooling over China, different from troposphere warming in the Northern Hemisphere, maybe has some relationship with weaking and southward displacing of middle latitude upper westerlies over East Asia. Obvious surface warming in winter and troposheric cooling in spring have,also been found in most areas of China.