近50年三江源地区低云量变化特征及与其他气候因子的关系

为了探究三江源地区低云量的变化趋势以及与相关气候因子的关系,利用三江源地区同德气象局1961—2010年50年的低云量观测资料,分析低云量的变化特征及与相关气候因子的关系。结果表明,自1961年以来该地平均低云量呈显著增加趋势,四季平均低云量均呈增加趋势,春季、夏季和冬季低云量增加趋势显著。月平均低云量分布呈双峰型,6、7月是一年中低云量最多的月份,12月为最低值。突变分析表明,年、春季平均低云量分别在1964年、1965年发生了由多到少的突变,2002年、2001年发生了由少到多突变;秋季低云量在1963年发生了由多到少的突变;冬季低云量在2000年发生了由少到多的突变;夏季低云量未发生突变。对低云量影响最大的是平均气温、水汽压因子;其次是日照时数;再次平均风速。

Variation of Low Cloud Amount and Its Correlation with Climatic Factors in Recent 50 Years in Three-River Source Region

Based on the the data of cloud amount during 1961-2010 form Tongde meteorological station in the Three-River Source region, the variation of the low cloud amount was analyzed, and also the relationship between cloud amount and interrelated climatic factors was discussed. The results showed that the mean amount of low cloud increased significantly since 1961,four seasons mean amount of low cloud showed an increasing trend,spring,summer and winter mean amount of low cloud increased significantly. Average low cloud cover is bimodal distribution, June and July are the low cloud cover in most months of the year, December was the lowest value. Mutation analysis indicates that the mean low cloud of year and spring took place in 1964,1965 by most to least, and from least to most in 2002,2001;the mean low cloud in autumn abrupt change took place in 1963 from most to least; the winter abrupt change took place in 2000 form least to most; the summer was not mutated. the temperature and water vapor pressure factor is being affect most to low cloud amount; followed by hours of sunshine ;the third is average wind speed.