摘要
应用NMC17年热带格点风及OLR资料,对比分析了厄尼诺年与反厄尼诺年热带环流的差异,发现厄尼诺现象使多年平均位于西太平洋上的最强盛的对流加热区东移到中太平洋,太平洋热带地区东西向对流加热梯度减弱,造成中东太平洋上的Walker环流及西太平洋与印度洋上的反Walker环流场比常年减弱;同时,厄尼诺现象也使中东太平洋地区经向反Hadley环流及美洲大陆上空的Hadley环流减弱。
Using the tropical grid wind data and OLR data set of NMC for 17 years. we have comparedthe tropical circulation of typical E1 Nino year with that of the La Nina year. It is found that inE1 Nino year the strongest convective region which is climatologically located in the equatorialwestern Pacific is weakened and moved eastward to the central Pacific, and the east—west heat-ing gradient becomes smaller. Therefore. both the Walker circulation over the central—easternPacific and the anti- Walker circulation over the western Pacific and Indian Ocean would beweakened. Meanwhile, the E1 Nino event would also weaken the anti-Hadley circulation over thecentral and eastern Pacific and the Hadley circulation over the American continent.
