1951-2010年喀什绿洲降水量变化特征研究

Analysis on the Variation Characteristics of Precipitation in Kashgar Oasis During 1951-2010

利用新疆喀什站1951-2010年年降水量资料,采用Morlet小波函数、Mann-Kendall突变检验等方法对其年降水变化趋势、变化周期、降水量突变情况进行分析.研究结果表明:喀什绿洲1951-2010年60a间年降水量呈上升趋势;该区气候干旱,研究时间段内多年平均降水量67.15mm,而且降水年际变化较大,最大年降水量为2010年的191.60mm,最小年降水量为1994年的16.20mm,年降水量变差系数0.53,极值比11.83;突变检验结果显示年降水量在1997年发生明显的突变;研究区1951-2010年间年降水量存在2个明显的变化主周期,分别为5a和12a,同时还存在30a左右大尺度震荡周期.

In this study,the Morlet wavelet function analysis and Mann-Kendall abrupt change analysis were used to analyze the annual precipitation change trend,fluctuation periods and abrupt change in Kashgar,Xinjiang Uygur Autonomous Region,China during the period of 1951-2010 based on the annual precipitation of Kashgar station.The results show that the annual precipitation in 60 years from 1951 to 2010 of Kashgar oasis was in a increasing trend;the climate in the studied area is dry and in the research period the average annual precipitation is just 67.15 mm,and the inter annual variation of the rainfall is larger,the maximum annual precipitation is 191.60 mm in 2010,and the minimum annual rainfall of 16.20 mm in 1994,the annual precipitation quantity difference coefficient 0.53,extreme value more than 11.83 mutations.Results of abrupt change analysis show that the annual precipitation occurred obvious mutation in 1997;there are 2 obvious changes in the main period of the annual precipitation in this region during 1951-2010,respectively 5 years and 12 years,there is also a large scale oscillation cycle about 30 years.