伊犁河谷春夏季极端天气气候的变化分析

Extreme Weather and Climate Change over Yili Valley in Spring and Summer

利用1961—2005年降水、气温、冰雹、大风资料,分析了伊犁河谷春夏季极端天气气候事件的长期变化趋势。结果发现暴雨(日降水>24mm)频次20世纪90年代以后明显增加,分析最大日降水量发现,降水强度也明显增大,这和伊犁河谷降水变化趋势是一致的;春夏季极端温度的变化不显著,夏季极端高温频次和强度有微弱的减小,春季极端低温频次和强度也有微弱的减小;春夏季伊犁河谷冰雹和大风极端天气显著减少。

Using the observational data of precipitation, temperature, hail, gale during 1961-2005, the long-term climate change trend of extreme weather and climate events over Yili Valley in spring and summer were analyzed. The results showed that the frequency of rainstorm （daily precipitation 〉24mm） have being increased obviously since 1990s, Precipitation intensity established by maximum daily precipitation analysis also increased significantly. The trend was consistent with precipitation variation tendency over Yili Valley.However, spring and summer extreme temperature changes there were not significant, and the frequency of extreme heat and the intensity in summer had a slight decrease,the frequency of the extreme low temperature and intensity in spring also decreased slightly. But hail and gale over Yili Valley in spring and summer reduced significantly.