根据位于巩乃斯河谷的天山积雪雪崩研究站近30年来的年最大雪深、月平均气温、月降水量观测记录,用平均差值法、最小二乘法、自回归滑动平均法检验了天山西部中山带积雪、冷季降水、冷季平均气温的变化趋势,结果表明,天山西部中山带积雪呈增加趋势,近30年来年平均增加1.43%,与青藏高原、南极大陆及格陵兰冰盖表面积雪积累增加相一致.天山西部中山带冷季气温和降水的变化趋势也是增加的,其中冷季降水平年平均增加0.12%,而冷季气温升高了0.8℃,积雪与冷季气温之间存在着弱的负相关关系,而与冷季降水呈显著的正相关关系.积雪的增加主要是因为气候变暖引起的冷季降水的增加对积雪增加的贡献大于由于冷季气温升高而造成积雪减少的贡献的结果.
On the basis of observed records of daily snowcover depth,monthly average temperature and monthly total precipitation at Tianshan Mountains Snowcover and Avalanche Station in the valley of the Kunes River,three trend estimates about the snowcover depth,cold season precipitation and cold season temperature by using the difference of average,least square fitting and slope AR(1)process are made. The results show that an increasing trend of the snowcover depth is very significiant in the middle mountains of western Tianshan in the last 30 years or so.The change trend coincides with the snowcover change trend over the Tibetan Plateau,and the snowcover accumulation increases in Antarctica and Greenland.The secular trend of cold season temperature and precipitation is increasing as well.In the last 30 years,the annual accumulation of snowcover increases 1.43%,the annual increasing rate of cold season precipitation is 0.12%,and the cold season temperature has increased 0.8℃.A significant positive correlation exists between snowcover and cold season percipitation,but the correlation between snowcover and cold season temperature is negative.The increases of snowcover mainly result from the increases of cold season precipitation,which occurred in the background of global climate warming.
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