热带夏季风对ENSO的非线性响应  

The Nonlinear Response of the Tropical Summer Monsoon to ENSO

作　　者：郭品文[1] 姜玥宏 王群 

机构地区：[1]南京信息工程大学气象灾害省部共建教育部重点实验室,江苏南京210044 [2]盐城市气象局,江苏盐城224500

出　　处：《南京气象学院学报》2008年第6期774-781,共8页Journal of Nanjing Institute of Meteorology

基　　金：江苏省高校自然科学研究计划项目(05KJB170072)

摘　　要：采用1950—2002年NCEP/NCAR53 a夏季平均的850 hPa低空风场和GISST海温资料,通过非线性典型相关分析(Nonlinear Canonical Correlation Analysis;NLCCA),得到热带夏季风对ENSO的响应存在一定的非线性。强La Nina年与强El Nino年相比,环流中心明显偏西偏南,澳大利亚上空出现了一个异常的反气旋系统,风场强度也有很大的差异。当海温正异常或负异常变化时,非线性主要表现在强度上;当海温由正(负)异常变为负(正)异常时,非线性在强度和流型上都有很清楚的表现。热带夏季风对ENSO的响应可分为线性和非线性响应,这两部分分别解释方差的67.45%和32.55%,孟加拉湾—中南半岛西部和菲律宾群岛以西的异常环流主要是由非线性响应引起的。Basing on the NCEP/NCAR 850 hPa averaged wind field in summer and the SST data of GISST from 1950 to 2002 ,the result that there is some nonlinear relationship between the tropical summer monsoon and ENSO is obtained by using the nonlinear canonical correlation analysis. Compared to strong E1 Nino year, there is an abnormal anticyclone over Australia with large difference in wind fields intensity, the location of the circulation center is westward and southward in strong La Nina year. When the SSTA is positive or negative anomaly, the nonlinear response presents as the intensity of the wind field ; while the SSTA is changing from positive （negative） to negative （positive） departure, both the in- tensity and the circulation pattern represent nonlinear features clearly. The response of the tropical sum- mer monsoon to ENSO obtained from the NLCCA projection can be separated into a linear and a non- linear component, they accounted for 67.45 % and 32.55 % variance, respectively. In summer, the anomaly circulations over the Bay of Bengal, indo-china Peninsula and the west to Philippines Archipelago are induced by the nonlinear component.

关 键 词：热带夏季风 非线性典型相关分析(NLCCA) 神经网络 非线性 

分 类 号：P425.42[天文地球—大气科学及气象学]