冬夏东亚季风环流对太平洋热状况的响应

冬夏隔季韵律关系一直是我国长期天气预报和短期气候预测的一个重要依据,然而迄今为止对它们之间的物理过程及成因机理并不十分清楚。利用NCEP/NCAR全球2.5°×2.5°网格月平均再分析资料,研究1951~2000年冬夏东亚季风环流异常变化与太平洋海面温度(SST)的关系及对关键海温区响应机理。研究指出:冬夏东亚季风环流隔季韵律关系及其年际变化与赤道东太平洋海面温度异常(SSTA)变化密切相关,冬季赤道东太平洋出现La Ni~na(El Ni~no)型的SST分布,有利冬、夏东亚季风环流加强(减弱),其影响过程通过赤道Walker环流强(弱)以及东亚地区Hadley环流强(弱)过程完成。冬季赤道东太平洋海温变化是冬、夏东亚环流季节以及年际变化的一个重要外强迫因子。

The Response of East Asian Monsoon Circulation between Winter and Summer to Sea Surface Temperature over the Pacific Ocean

The response of East Asia monsoon circulation between summer and winter to sea surface temperature over the Pacific Ocean is investigated using the NCEP/NCAR reanalysis dataset during 1949-2000.The study focused on the cases that the intensity of East Asian monsoon!circulation between winter and summer were similarly.It had been found out that the intensified(weakened) East Asian monsoon circulation both in winter and summer were associated to the stronger(weaker) Walker circulation in equatorial Pacific and Hadley circulation over East Asian.The variation of the intensity for Walker circulation in equatorical Pacific and the Hadley circulation over East Asian are affected by the variation of sea surface temperature anomaly(SSTA) over equatorial eastern Pacific.It had been pointed out that the East Asian monsoon circulation in both of winter and following summer became stronger(weaker) in La Nia(El Nio) years.The sea surface temperature(SST) over equatorial eastern Pacific was the most important force factor for the seasonal and annual variation of East Asian monsoon circulation.