| This paper preliminarily reconstructs climate change of Tibetan Plateau and contiguous regions during the past 50 years, by using the long-term observation data from 140 Weather Stations and under the usage of ARC/INFO software.The author found that the temperature decline dramatically in the I960' s in most area of Tibetan Plateau and it was the coldest period in the past 50a and the temperature began to rise up in the 1970' s, at the mid-west regions of the Plateau. But in the east of the Tibetan Plateau and Sichuan Basin, the temperature dropped down successively from 1970' s to 1980' s. The temperature increased notably in the 1990' s for almost all the regions. The temperature change in the Tibetan Plateau had the spatial characteristics from the westto the east part of the Plateau. There exist some relationships between the temperature range and the altitude. But the variation range do not always increase along with the elevation, the altitude of 2000 m is seemingly the controlling elevation.The variation of mean temperature in January has the similar tendency to annual temperature change. The mean temperature of January has the supreme increase in the regions where the annual temperature has the supreme increase. This means that in the most regions, the temperature increase in winter, especially in January has done the most contribution to the increase of annual temperature. But we should know that there were in spatial and temporal differentiation between the mean temperature of January and annual. The variation of the lowest-mean temperature of January has the similar tendency to the mean, but the variation scope is bigger than the mean. The similar turn up in the variation of the highest-mean temperature in January, but the variation scope is smaller than that of the mean temperature. In some regions, the variation tendency of the highest-mean temperature of January isn' t similar to the mean temperature. All of these showed the complication of temperature change in space and time.The increase of mean temperature in July had the featuresof starting from the west and propelling to the east for the Tibetan Plateau and contiguous regions in the past 50a, just as the mean temperature of annual. The tendency of mean temperature variation in July is similar to the annual mean temperature variation and the variation range is smaller except that in the 1990' s the decline range of July mean temperature is bigger than that of annual mean temperature. And we found that the change of July temperature has important contribution to the variation of annual temperature. The lowest-mean temperature in July has the similar variation tendency and bigger range in the regions where the variation range of mean temperature in July more than 0.5℃, but when the variation range of mean temperature in July not more than 0.5℃, the variation range of lowest mean temperature in July is small and the tendency not always same to mean temperature in July. In July the highest mean temperature has the similar variation tendency to the mean temperature.There are considerable differences in the variation tendency and range between mean temperature in January and July, especially in the Sichuan Basin. In this area, the temperature in July increased and cause the annual temperature increased in the 1980' s but the temperature in January declined. In the1990' s, the tendency of temperature variation is just contrary to 1980' s.There is not notably relationship between the variation of temperature and precipitation in the time-scope of 10a. There will take up warm-wet, cold-wet, warm-arid and cold-arid conditions regionally. Generally in the past 50a the precipitation increased adapt to the increase of temperature in the Tarim Basin, Hexi Corridor and most region of the Tibetan Plateau. But the increase of precipitation can't change the arid physical geology conditions of northwestern China. In the regions where precipitation has been more affected by the Southeast Moonsoon and the precipitation notably declin...
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