The combined effects of the ENSO and the Arctic Oscillation on the winter climate anomalies in East Asia
The combined effects of the ENSO and the Arctic Oscillation on the winter climate anomalies in East Asia
复制标题
ENSO和北极涛动对东亚冬季气候异常的综合影响
DOI：
10.1007/s11434-012-5654-5
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发表时间：
2013-04-01
影响因子：
--
通讯作者：
Ma Yin
中科院分区：
文献类型：
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作者：
Chen Wen;Lan XiaoQing;Ma Yin
以厄尔尼诺和南方涛动(ENSO)的冷暖位相为背景，利用NCEP/DOE再分析2资料和我国站的气温和降水资料，研究了北极涛动(AO)月变化对东亚冬季气候异常的影响。ENSO和AO的共同作用表明，冬季气候异常主要受中国北部的AO和中国南部的ENSO的影响，此时，厄尔尼诺现象对AO月为负，而拉尼娜现象对AO月则为正。中国的这些气候异常与前人提出的气候异常机制是一致的。然而，除中国北部的温度异常仍主要受AO的影响外，厄尔尼诺现象和拉尼娜现象都呈现出不同的气候异常模式，而厄尔尼诺现象与厄尔尼诺现象发生在一起。进一步分析认为，其原因在于平流层-对流层相互作用和温带相互作用的差异。前者冬季纬向对称环流占优势，温带相互作用减弱。因此，ENSO和AO对东亚气候的影响主要表现为线性组合效应。相反，在后一种情况下，环状大气环流模式不被看好，温带相互作用较强。因此，ENSO和AO对东亚冬季气候的联合作用呈现出非线性特征。
With the warm/cold phases of the El Niño and Southern Oscillation (ENSO) as a background, the impacts of monthly variation in the Arctic Oscillation (AO) on the winter climate anomalies in East Asia are studied with the NCEP/DOE Reanalysis 2 data and the Chinese station data regarding temperature and rainfall. The combined effects of ENSO and the AO indicate that the winter climate anomalies are mainly influenced by the AO in northern China and the ENSO in southern China, when an El Niño couples with a negative AO month or a La Niña couples with a positive AO month. These climate anomalies in China are consistent with the mechanisms proposed in previous studies. However, most of China presents a different pattern of climate anomalies if an El Niño couples with a positive AO month or a La Niña couples with a negative AO month, with the exception of the temperature anomalies in northern China, which are still affected dominantly by the AO. Further analysis suggests that the causes are attributed to the differences in both the stratosphere-troposphere interaction and the extratropics-tropics interaction. In the former cases, zonal symmetric circulation prevails in the winter and the extratropics-tropics interaction is weakened. Thus, the influences of the ENSO and the AO on the East Asian climate mainly present linear combination effects. On the contrary, an annular mode of atmospheric circulation is not favored in the latter cases and the extratropics-tropics interaction is strong. Hence, the combined effects of the ENSO and the AO on the winter climate in East Asia present nonlinear characteristics.