近40年来科尔沁沙地沙漠化过程的气候背景分析

Analysis of Climatic Background in Desertification Processes in Horqin Sand Land for the Past 40 Years

本文利用时间序列分析中的滑动平均和短期预测方法分析了科尔沁沙地的 8个气象台站 1 961～ 2 0 0 0 ( 1 998)年多年气温和降水量数据的变化趋势 ,并用简单气候偏差指数计算了逐年的降水量变差 ;同时用变异系数计算了 8个站点 1 961～ 2 0 0 0 ( 1 998)年的降水量年际变差。结果表明 ,近 40年来 8个站点的年均温度呈现显著的直线上升趋势 ,平均增温 1 .5 1℃ ,增温幅度在 0 .90～ 1 .79℃ ;年均温增加主要表现在冬季增温和春季增温 ,而年降水量未发现显著上升或下降的趋势。但从降水季度分布来看 。

Fluctuations and trends of temperature and precipitation in eight meteorological stations in Horqin Sand Land during the periods of 1961-2000 were calculated to analyze climate variation in short term scale. Moreover, two methods of simple climate departure index and variation coefficient (CV%) were used to analyze inter-annual variation of precipitation for those stations. The results showed that annual mean temperatures all have a significant increase about 1.51℃ for the past 40 years, from 0.90~1.79℃, and the annual mean temperatures was mainly ascended in winter and spring. Whereas, no significant trends were found from precipitation data. Furthermore, the precipitation data was analyzed according to the proportion of four seasons, which showed that the percentage of precipitation in spring was increased dramatically.