青海省海西州德令哈地区近千年来年降水量变化特征分析  

STATISTICAL CHARACTERISTICS OF ANNUAL PRECIPITATION VARIATION DURING THE PAST 1 000 YEARS IN DELINGHA, QINGHAI PROVINCE, CHINA

作　　者：刘洪滨[1] 邵雪梅[2,3] 黄磊[2] 梁尔源[2] 方修琦[4] 王丽丽[2] 

机构地区：[1]中国气象局气候研究开放实验室 [2]中国科学院地理科学与资源研究所 [3]中国科学院青藏高原研究所,北京100085 [4]北京师范大学

出　　处：《第四纪研究》2005年第2期176-183,共8页Quaternary Sciences

基　　金：中国科学院知识创新工程重要方向项目(批准号:KZCX3-SW-321);国家"十五"科技攻关项目(批准号:2001BA611B-01)资助

摘　　要：试图揭示位于我国青藏高原东北部的青海省海西州德令哈地区近千年来世纪尺度年降水量变化规律.分析结果表明,该地区近千年年降水量变化存在显著的多尺度周期变化特征,其中以13～18世纪中的200年主控周期最为明显,并在15～17世纪达到最强,而近200年则以准120年的周期振荡为主,且在19世纪两种主要周期变化趋势相反,在近百年又趋向一致.年降水量序列的均值突变一般以30～100年尺度最为明显,世纪尺度的均值突变时段分别为公元1100～1111年、1403～1449年及1615～1661年,表现为年降水量的减少,以及公元1321～1348年、1497～1557年、1728～1743年及1885～1891年,表现为年降水量的增加.200年以上时间尺度的方差突变主要表现为序列的低频变化幅度,从公元1220年前后至1580年前后持续增大,且以15世纪的方差突变最为明显.Climate change has been an important issue in the present world. The annual or the seasonal precipitation changes are directly relative to agriculture, stock raising, and forest productions, and it has been a focal point in climate change and some relative research fields. In order to study the statistical characteristics of annual precipitation variation for the past 1 000 years in Delingha, Qinghai Province, Northwest China, the wavelet spectral analysis, the singular spectrum analysis and the scanning tests were applied for the reconstruction of time series from seven chronologies built by tree ring samples collected in mountains along northeastern margin of Qaidam Basin. The periodical signals in the precipitation series can be detected by the first two statistical methods mentioned above, and the last method is applied to figure out the abrupt change signals imprinting in the same series. The quasi-200-year cycle was present during the whole time period (A.D.1000～2001) of the series, especially in the period of A.D.1200～1800, being more intense during A.D. 1440～1640. From the end of the 18th century and the beginning of the 19th century to present, the dominant cycle changed gradually from quasi-200-year cycle to quasi-120-year cycle. The phases of these two dominant cycles are opposite in the 19th century, that the quasi-200-year cycle was in positive phase and the quasi-120-year cycle was in negative phase in the first half of the 19th century, and the phases are reverse in the second half of the same century. From the beginning of the 20 century, the phases of the two dominant cycles tended to become uniform, that the two phases are all in negative phase. The central time period (A.D.1920～1940) of this negative phase is in agreement with other studies on lower water time period of A.D.1922～1932 over the Yellow River basin. The reconstructed series by the first four empirical orthogonal functions, which represent the quasi-200-year cycle and the quasi-120-year cycle, from singular spectral analys

关 键 词：中国西北地区 年降水量 百年尺度 周期变化 气候突变 

分 类 号：P468[天文地球—大气科学及气象学]