近60年科尔沁沙地的气候变化

Climate changes in Horqin Sandy Land in recent 60 years

处于季风边缘带的科尔沁沙地气候变化具有复杂性和敏感性特征,文中采用线性倾向估计、非参数检验等方法探讨了其变化规律。结果表明:近60年研究区的年均气温呈上升趋势,变化速率为0.37℃/10a,尤其是20世纪80年代中后期以来增温趋势更为明显。且年际极端最高、最低气温也呈上升趋势。在季节变化中,春、冬季增温明显,夏季和秋季变化略小。而年降水量呈稳中有降的总趋势,变化速率为-13.54mm/10a。且年际、季节的降水日数也出现减少趋势。在季节变化中,除了春季以外其它季节均有减少趋势,与SPI变化一致。气温与降水量总体上呈负相关关系,即气温上升与降水的减少相对应,因而该区气候变化呈暖干化总趋势。夏季气候变化与东亚夏季风强弱有一定联系。

Climate changing is complex and sensitive in the monsoon marginal zone of Horqin Sandy Land. We discussed its variation of the features with linear trend method and nonparametric tests in this research. The results indicated that during the approximate 60 years from 1951 to 2010, the annual mean temperature in the Horqin Sandy Land showed a trend of increase by 0.37℃ per ten year. Especially, the annual mean temperature increased remarkably since the mid 1980s of 20th Century. In addition, annual extreme maximum and minimum temperature showed a trend of increase. The increase of temperature in spring and winter were more obvious than that of summer and autumn. The changes of the precipitation in Horqin Sandy Land were not significant, hut with a weak decreased tendency by 13.54ram per ten year in the last 60 years. The inter annual and seasonal precipitation days also showed a trend towards decline. Seasonal changes of rainfall in addition to the spring, there was a decreased tendency, were consistent with SPI. Therefore, climate change of the study areas was the general trend of warm and dry. Analysis showed that the climate changes of summer is controlled by the summer monsoon intensity in East Asia.