新疆伊犁河谷地区50a来气候变化特征分析

根据伊犁河谷地区10个气象代表站点的气温及降水资料,利用线性趋势函数及t检验法分析了该地区近50 a的气候变化特征。结果表明,伊犁河谷除夏季平均最高气温与年平均最高气温无明显变化趋势外,年平均气温、其他各季平均气温、平均最高气温、平均最低气温均呈上升趋势,平均最低气温上升的幅度远大于平均最高气温的上升幅度,其中,冬季增幅最大,为0.59℃/10 a,秋季次之;暖温年多发生在20世纪80年代后,且近10 a是50 a中最暖的时期,冷温年多发生在20世纪六七十年代;平均气温异常年份为:1969年为异常偏冷年,2010年为异常偏暖年;50 a全年降水量变化呈增湿趋势,变化倾向率为15.4 mm/10 a,其中,夏季降水量为50 a中最多时期,冬季次之,秋季降水量为最少;20世纪六七十年代为枯水期,八九十年代至今为丰水期,但分布不均匀,阶段性干旱时有发生,降水偏多趋势还将继续。

Climate Change Characters in Recent 50 Years in Yili Valley Xinjiang

Based on the data of temperature and precipitation at ten representative meteorological stations in Yili Valley in recent 50 years,this paper analyzed the climate change characters with methods of the linear fitting and t-test.The results showed that,in Yili Valley,the average summer maximum temperature and average maximum temperature showed no significant change trends,but the annual average temperature,average maximum temperature,average minimum temperature showed an upward trend,and the increase of the mean minimum temperature was much higher than that of the maximum one.The largest increase was in winter by 0.59 ℃/10 a,and it took the second place in autumn.High temperature occurred mostly after the 1980s,the recent 10 years was the warmest in recent 50 years,and the low temperature occurred mostly during the period from the 1960s to the 1970s;the mean temperature anomalous years were the following: year of 1969 was a somewhat cold year,while 2010 warm;the annual precipitation in 50-year period showed a trend of rising humidity with a change tendency of 15.4 mm/10 a,namely,the most maximum rainfall happened in summers,winter followed,and autumn the least;the 60s and 70s were dry seasons,and the 80s and 90s abundant water years,but with uneven distributions and periodical droughts time to time.The trend of relative higher precipitation will continue.