春季赤道东太平洋海温异常与东亚夏季风的关系

Relation of eastern Asian summer monsoon with the equat orial eastern Pacific spring SSTA

摘要:

定义了新的东亚季风指数,分析表明该季风指数能够更好地反映西太平洋副高的季节变化和年际变化。以此为基础讨论了春季赤道东太平洋海温异常、夏季西太平洋副高及东亚夏季风三者之间的关系,指出春季赤道东太平洋海温偏暖年,夏季西太平洋副高偏南、偏强、偏西,东亚夏季风偏弱,长江流域夏季多雨,华南、河套及其以东地区少雨;春季赤道东太平洋海温偏冷年则反之。

Abstract:

Defined is a new east Asian monsoon index ,which can perfectly describe the seasonal and interannual change of the wester n Pacific subtropical high(WPSH).On the basis of the index,the relations are discussed among the equatorial eastern Pacific spring SSTA,the summer WPSH and east Asian summer monsoon.Related to the warm(cold) spring SSTA in the equatorial eastern Pacific,the summer WPSH position lies to the south(north) of its mean,the west(east) of its normal,and is slightly intensified(weakened); the east Asian summer monsoon is also weak(strong),the mid/low reaches of the Yangtze River are hit by floods(droughts),accompanied by droughts(floods) in the south China and the Yellow River valleys.