西天山北坡地区近50年来气温和降水变化分析

Analyses on Variations of the Temperature and Precipitation in the North Slope Area of the Western Tianshan in the Recent 50 Years

[目的]分析西天山北坡地区近50年来气温和降水的变化特征。[方法]根据西天山北坡地区3个气象站1961～2010年的气温、降水资料,利用线性趋势分析法及5年滑动平均等方法,分析了该地区50年来的气候变化。[结果]西天山北坡地区气温呈现明显增暖趋势,近50年的年均温以0.3℃/10a的速率显著升高,但各季节温度上升率不同,秋季〉冬季〉春季〉夏季。西天山北坡地区50年来的年降水量总体呈相对增多趋势,从年降水量来看,平均以16.9 mm/10a的速率明显增加;从季节降水量来看,除秋季外,其他3个季节在近50年表现出显著的增加趋势,增幅为3.2～11.2 mm/10a,夏季增幅最大,秋季经历了80年代的降水小高峰后,近20年降水量略有下降。[结论]西天山北坡地区气候呈现暖湿化趋势。

[ Objective ] The research aimed to analyze variation characteristics of the temperature and precipitation in the north slope area of the Western Tianshan. [ Method] According to temperature and rainfall data from 1961 to 2010 at three meteorological stations in the north slope area of the Western Tianshan, climate change in the zone in recent 50 years was analyzed by using linear trend analysis method and 5-year moving average method. [ Result ] The temperature in the north slope area of the Western Tianshan showed significant warming trend. The annual average temperature significantly increased at O. 3 ℃/10a in recent 50 years. But the rise rates of temperature in different seasons were different ： autumn 〉 winter 〉 spring 〉 summer. The annual rainfall in the north slope area of the Western Tianshan in recent 50 years total presented relative increase trend. Seen from annual rainfall, it significantly increased at 16.9 mm/10a. Seen from seasonal rainfall, except in autumn, rainfalls in other three seasons in the past 50 years showed significant increase trend, with amplitude of 3.2 - 11.2 mm/10a. The largest increase amplitude was in summer. After a small precipitation peak in the 1980s, autumn rainfall slightly declined in the past 20 years. [ Conclusion] The climate in the north slope area of the Western Tianshan become warm and wet.