民勤沙区46a主要气候特征及其变化趋势研究

Study on Characteristics and Variance Tendency of the Main Climatic Factors in Minqin Desert Area in Recent 46 Years

本文通过对民勤沙区不同气象因子分析,研究了不同年代气候特征及其演替变化趋势。结果表明:(1)随着时间的变化,气温的变化有不断增温趋势,每年平均增温0.28℃,以冬季上升最明显达0.38℃,这一点和全球气候变暖是一致的。(2)地温的变化和气温的变化是一致的,有不断增温趋势,地温比气温增温更明显。(3)降水量在年际之间有递增的趋势,虽然有波动现象,但仍然在其平均线上波动。从60年代到21世纪基本经历了一个"少、多、少、多"的年代际变化过程;(4)地下水位变化呈直线下降趋势,直线倾向率是0.6897;(5)蒸发量在年际之间有递减的趋势,直线倾向率是-20.5,其年代际变化过程与降水量恰恰相反。

Characteristics and variance tendency of the mainly climatic factors for the 46 years in Minqin Desert Area was studied. Results showed that ： （ 1 ） From 1961 to 2006, variance tendency of annual air - temperature was increasing continuously, average increment of each year was 0.28℃ , especially in winter, its average increment was up to 0.38℃, which was due to the variance tendency of global climate change. （2）The change tendency of soil - temperature was consistent with air- temperature change, and the increment of soil -temperature was more obvious than air temperature. （3） The annual precipitation was increasing in the 46a although there was some fluctuant phenomenon. The annual precipitation experienced a variable course that was ＂less, more, less, more＂. （4） The variance of underground water level variety was presented point - blank trend, of which the inclined rate was 0. 6879. （5） The annual evaporation in these years was decreasing gradually, the incline rate of straight line was - 20.5, and the change of annual evaporation was contrary to that of precipitation.