乌鲁木齐城区近40年来降水量的变化特征

利用线性回归、气候趋势法及R/S等数理统计方法,对乌鲁木齐地区1971 ～2010年5个测站逐日的降水量变化进行研究.结果表明,近40年乌鲁木齐地区降水量呈上升趋势,气候倾向率为22.29 mm/10a;而年平均降水日数也呈上升趋势,但相比较降水量的增加来说,降水日数的增加不是很明显,其气候倾向率为1.12 d/10a,其中市区降水天数增加的最为明显;除秋季外,其余季节降水量均呈增加趋势,而四季的降水日数均呈正趋势,各站逐月降水量和降水日数分布表现不一致;乌鲁木齐地区降水量和降水日数的R/S分析结果表明,在未来的一段时间内两者均保持着上升趋势.

Variation Features of Precipitation in Urumqi Region in Recent 40 Years

The daily precipitation of the five meteorological stations in Urumqi from 1971 to 2010 were studied by using the methods of linear regression,climate trend method and rescaled range analysis （R/S） method.The results showed that the average annual rainfall overall presented an increasing trend at the variation tendency rate of 22.29 mm/10a in the Urumqi region in recent 40 years.The precipitation days also increased,but compared with the precipitation amount,the increase of precipitation days is not obvious with the tendency rate of 1.12 d/10a,and urban precipitation days increase most obvious.In addition to the autumn,the other season precipitation were increased,trends of fourseason precipitation days were all positive,monthly precipitation and precipitation days distribution performance is inconsistent in five stations.R / S analysis showed precipitation quantity and precipitation days will maintain an upward trend winthin a period in the future.