新疆阿拉山口1971至2017年高温天气特征分析

Analysis on the Characteristics of High Temperature Weather from 1971 to 2017 in Alashankou

阿拉山口夏季易出现高温酷暑天气,给该地区经济建设带来了一定程度的影响。本文通过统计该地1971至2017年高温天气气候特征得出高温日数随时间变化基本维持略下降。高温在5至9月均有出现,主要出现在6至8月,而7月既是高温日峰值又是极端高温日峰值出现的月份。高温初日平均日为5月29日,近47年总体呈缓慢推后的趋势;阿拉山口高温终日平均为8月27日,高温终日总体呈提前趋势。高温天气在1971年至1973年偏少,1974年至1986年偏多,1987年至1996年偏少,1997年至2009年为震荡期即年高温日数偏多与偏少交替出现,2010年开始年高温日数呈现偏少趋势;极端高温年与高温年的趋势大体相同。欧亚范围内三槽两脊的环流形势对阿拉山口出现极端高温有很好的指示意义。

Alashankou is prone to high temperature and hot summer weather, which has brought a certain degree of impact on the economic construction of the region. According to the characteristics of high temperature weather and climate from 1971 to 2017, the number of high temperature days decreased slightly with time. High temperatures occur from May to September, mainly from June to August, and July is both a peak and an extreme peak. The first high temperature in 47 years occurred on May 29, showing a trend of slow delay. The average calculation of the last occurrence of high temperature every year is August 27. There is an earlier trend. High temperature weather is less from 1971 to 1973, more from 1974 to 1986, less from 1987 to 1996, more and less from 1997 to 2009 in the oscillation period;that is, the number of high temperature days is more and less, and the number of high temperature days is less from 2010. The trend of extreme hot years is roughly the same as that of hot years. The circulation pattern of the three troughs and two cristae in the Eurasian region is a good indication of the extreme high temperature in Alashankou.