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根据 １９８２—１９９２年期间的日平均 ＭＳＵ（Ｓｐｅｎｃｅｒ， １９９３）海洋降水和 ５天平均的ＣＭＡＰ（Ｘｉｅ＆ Ａｒｋｉｎ， １９９７）降水观测资料，分析了热带太平洋大气季节内振荡（ＭＪＯ）的年际变化特征。在太平洋海表温度（ＳＳＴ）年际变化的正常年份（１９８２—８３年， １９８６—８８年， １９９１—９２年），均有明显的ＭＪＯ信号传到日界线以东并在中、东太平洋维持数月。热带ＭＪＯ活动强度的年际变化与局地ＳＳＴ的变化存在正相关。中、东太平洋降水的季节内振荡的年际变化与热带太平洋ＳＳＴ的最强正相关在Ｎｉｎｏ３区附近。以观测ＳＳＴ场强迫ＣＣＭ３大气模式的数值试验基本上真实地再现了１１年期间热带太平洋降水季节内振荡的年际变化总趋势，但模拟季节内振荡的强度较观测平均偏弱。对比分别采用周平均和月平均ＳＳＴ强迫场的积分结果，发现在中、东太平洋，二个积分模拟的降水季节内振荡强度的年际变化接近并且趋势与观测基本一致，而在西太平洋二个积分的模拟结果差别较大。这表明在热带中、东太平洋，ＳＳＴ强迫的年际变化对ＭＪＯ强度的变化有强的制约。而在ＭＪＯ总体活跃的热带西太平洋，ＳＳＴ强迫场的季节变化对模拟ＭＪＯ活动也有较大影响。ＣＣＭ３模拟?
Based on the daily average MSU (Spencer, 1993) ocean precipitation and the five-day averaged CMAP (Xie & Arkin, 1997) precipitation data during 1982-1992, the interannual variability of MJO over the tropical Pacific Ocean was analyzed. In the normal year (1982-83, 1986-88, 1991-92) of the interannual variation of the Pacific SST, there was a clear MJO signal reaching east of the date line and maintaining in the Central and Eastern Pacific Months. The interannual variation of tropical MJO activity intensity is positively correlated with the change of local SST. The interannual variation of the intraseasonal oscillations of the precipitation over the East and Central Pacific is most positively correlated with the tropical Pacific SST near the Nino3 region. The numerical experiment of observing the SST field forcing the CCM3 atmospheric model essentially reproduces the general trend of the interannual variation of the intraseasonal oscillations during the 11-year tropical Pacific precipitation. However, the intensity of the simulated intraseasonal oscillations is weaker than the observed mean. Comparing the integral results of the weekly and average SST forcing fields respectively, we find that the interannual variation of the intraseasonal oscillation intensities of the simulated precipitation in two seasons in the eastern and eastern Pacific is close to and consistent with the observed trends. In the western Pacific, The result of integral simulation is quite different. This shows that in the tropical and eastern Pacific, the interannual variations forced by SST have strong constraints on the intensity of MJO. In the MJO, which is generally active in the western tropical Pacific, the seasonal variation of SST forced fields also has a significant impact on the simulated MJO activities. CCM3 simulation?