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将1~3月赤道东太平洋海表水温距平(SSTA)引入大气环流模式,模拟研究了ENSO(厄尔尼诺和拉尼娜)对其后东亚季风活动的影响。结果表明,由于SSTA在大气中强迫激发出了大气低频振荡,使得ENSO对其后的东亚季风活动仍有明显影响。厄尔尼诺之后的夏季,西太平洋副热带高压偏强偏北且西伸明显,中国东部降水偏少,尤其是华北地区;厄尔尼诺之后的冬季,东亚大槽偏深,冬季风偏强。拉尼娜之后的夏季,中国长江下游为异常副热带高压单体控制,江淮流域雨量偏少;拉尼娜之后的冬季,东亚大槽偏弱,东亚冬季风偏弱。厄尔尼诺的影响比拉尼娜的影响略强,两者的影响并非完全反相。
The SSTA of the equatorial eastern Pacific ocean from January to March was introduced into the atmospheric circulation model to study the effects of ENSO (El Niño and La Niña) on the subsequent East Asian monsoon activities. The results show that ENSO has a significant influence on the subsequent East Asian monsoon event because SSTA is forcibly excited by the atmospheric low frequency oscillation in the atmosphere. In the summer after El Nino, the western Pacific subtropical high is stronger than the north and the western stretch is obvious. Precipitation in eastern China is less than normal, especially in North China. In the winter after El Nino, the East Asian trough is deeper and the winter monsoon is stronger. In the summer following La Niña, the lower reaches of the Yangtze River in China were controlled by anomalous subtropical high-pressure singletons and the rainfall in the Yangtze-Huaihe River basin was less than normal. In the winter after La Nina, the East Asian trough was weak and the East Asian winter monsoon weakened. The impact of El Niño is slightly stronger than that of La Niña, and the impact of both is not completely reversed.