科尔沁沙地翁牛特旗气温的非对称变化分析

Unsymmetrical Variation of the Maximum and Minimum Air Temperatures in Wengniute Banner,Horqin Sandland

分析科尔沁沙地内蒙古翁牛特旗1957年以来逐月平均气温、平均最低气温、平均最高气温。结果表明:翁牛特旗近50年平均气温、日最高气温、日最低气温随时间均呈增加态势;日最低气温的增加量是日最高气温的11倍;1月最低气温的线性增加率为8.77℃/100 a,7月最高气温的线性增加率为3.12℃/100 a,其结果导致日较差减少;20世纪80年代后期年平均气温、日最高气温、日最低气温显著升高。

In this paper, the monthly average, minimum and maximum air temperatures in Wengniute Banner located in the Horqin Sandland since 1957 are analyzed. The results are as follows： （1） The annual average air temperature and the annual average daily maximum and minimum air temperatures are in an increase trend, the increase of annual average daily minimum temperature is more significant than that of annual average daily maximum temperature, and the effect of annual average daily minimum temperature on the annual average temperature is higher than that of annual average daily maximum temperature; （2） The increase of daily average mini- mum air temperature in January in Wengniute Banner is higher than that of annual average temperature and annual average daily minimum temperature, the change of daily average maximum temperature in January is not so significant and even decreased slightly in the 1990s; （3） The change of monthly temperature, average daily minimum and maximum temperatures in July is not so significant since recent 50 years, they have increased since recent 30 years, especially the average daily minimum temperature; （4） The linear change rate of minimum air temperature in January is 8.77 ℃/100 a, and that of maximum air temperature in July is 3.12 ℃ /100 a; （5） The annual average air temperature and the daily maximum and minimum air temperatures have sharply increased since the late-1980 s.