长江中下游降水以及东亚夏季风环流的年代际变化  

DECADAL CLIMATE VARIABILITY OF RAINFALL AROUND THE MIDDLE AND LOWER REACHES OF YANGTZE RIVER AND ATMOSPHERIC CIRCULATION

作　　者：王亚非[1] 高桥清利 

机构地区：[1]中国气象科学研究院,北京100081 [2]气象研究所

出　　处：《热带气象学报》2005年第4期351-358,共8页Journal of Tropical Meteorology

基　　金：热带海洋研究基金;科技部973项目2004CB418300;国家气候中心2003年开放课题共同资助

摘　　要：采用NCEP再分析资料及有关长江中下游的梅雨期降水量进行合成或诊断分析,目的是研究长江梅雨以及相应的大气环流的年代际变化,得出梅雨量的年代际变化和东亚大气环流以及厄尔尼诺现象的年代际变化密切相关的初步结果,具体结论如下:(1)与东亚季风指数相联系的长江中下游地区6～7月降水量及梅雨量在最近15年有持续增长的趋势。与此同时鄂霍茨克海地区的500hPa高度也有持续增长的趋势,并配合有厄尔尼诺频繁出现的趋势。(2)东亚夏季风指数与前年秋季NINO-3区域海温在最近20年有很好的相关,但是20年以前相关不好。意味着厄尔尼诺对东亚夏季环流的影响在加深。(3)近20年的PDO暖位相与东亚大气环流的年代际变化基本同步。This study examined the rainfall around the middle and lower reaches of the Yantze River and related atmospheric circulation by using NCEP reanalysis data. The purpose of this study is to analyze their decadal variation and the relationship among rainfall,atmospheric circulation around East Asia and the ENSO episodes. Current results are presented as follows： （1） Very clear increasing trend of the rainfall around the middle and low reaches of the Yangtze Rive during Meiyu period and June to July is found in recent 15 years.Meanwhile, the geopotential height at 500 hPa around the Okhotsk Sea also holds similar increasing trend. It is noticeable that ENSO episodes tend to occur more frequently in the recent 15 years. （2） An index describing East Asian summer monsoon is well correlated with the SST in Nino3 region in preceding autumn in the recent 20 years but is not prior to the period. This means that the E1 Nino phenomenon exerts more impacts on East Asian summer monsoon recently. （3） The warm phase of PDO in the recent 20 years basically coincides with the increasing trend of the atmospheric circulation in East Asia.

关 键 词：东亚夏季风 年代际变化 梅雨 长江中下游地区 降水 

分 类 号：P426.62[天文地球—大气科学及气象学]