121a梅雨序列及其时变特征分析  

Temporal evolution of 121a Meiyu series

作　　者：杨静[1] 钱永甫[1] 

机构地区：[1]南京大学大气科学学院,南京210093

出　　处：《气象科学》2009年第3期285-290,共6页Journal of the Meteorological Sciences

基　　金：国家自然科学基金面上项目(40675042);"国家重点基础研究发展计划"项目(2004CB418300)

摘　　要：对2001—2005年长江中下游梅雨期进行了划分。确定的梅雨参数包括梅雨集中期、梅雨长度、梅雨量、梅雨强度、入梅日期和出梅日期等。然后对1885—2005年共121a的长江中下游5站逐年的梅雨参数进行时间演变分析。从各梅雨参数趋势变化上可估计,在未来10a里,梅雨量仍将偏多,梅雨长度将偏长,入梅日期将偏早,出梅日期也将偏早。对梅雨参数进行Morlet小波分析得出,从1980s开始,入梅日期和出梅日期都出现明显的2～3a和6a的年际振荡周期;入梅日期还出现明显的12a左右的年代周期,出梅日期出现了16a左右的年代际周期。进入1990s后,梅雨长度出现了8a的年际周期,梅雨量则出现明显的4a和8a的年际周期以及一个近16a的年代际周期。According to the delimitation standard of Meiyu （plum rain） periods defined by Xu Qun, the Meiyu series was prolonged from 2001 to 2005, the parameters include Meiyu duration, Meiyu rainfall, Meiyu cumulative intensity, Meiyu beginning date and Meiyu ending date. The temporal evolution of 121 a annual Meiyu parameters of five stations in the mid-lower reaches of Yangtze River was analysed. The trend variations of Meiyu parameters show that both of the Meiyu duration and the Meiyu rainfall will increase, both of the onset date and the ending date of Meiyu will be in advance in the following 10 a. The periods of four Meiyu parameters are analyzed by Morlet wavelet analysis. It is found for both of the onset and ending dates of Meiyu period there are obviously interannual oscillations, the main periods are 2 -3 a and 6 a, the onset date of Meiyu also has a 12 a interdecadal oscillation and the ending date of Meiyu has a 16 a interdecadal oscillation since 1980. The Meiyu duration has 8 a period, the Meiyu rainfall obviously has 4 a and 8 a interannual periods and a 16 a interdeeadal period since 1990＇s.

关 键 词：梅雨时间序列 趋势变化 MORLET小波分析 

分 类 号：P426.623[天文地球—大气科学及气象学]