Tropical response to the Atlantic Equatorial mode: AGCM multimodel approach
Tropical response to the Atlantic Equatorial mode: AGCM multimodel approach
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DOI：
10.1007/s00382-009-0624-6
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发表时间：
2010-07
期刊：
影响因子：
4.6
通讯作者：
T. Losada;B. Rodríguez‐Fonseca;I. Polo;S. Janicot;S. Gervois;F. Chauvin;P. Ruti
中科院分区：
文献类型：
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作者：
T. Losada;B. Rodríguez‐Fonseca;I. Polo;S. Janicot;S. Gervois;F. Chauvin;P. Ruti
在AMMA-EU方案的框架下，分析了一个大西洋赤道模态（AEM）的敏感性试验，以探讨其对西非夏季降水异常的影响。该大西洋赤道模态的起源、发展和衰减与世纪后几十年的观测结果相似。最近的研究提出了AEM对下一次太平洋ENSO事件和印度季风的影响问题。本文利用上述AEM敏感性试验，评估了四种不同的大气全球环流模式的响应，以研究与大西洋厄尔尼诺模态相关的热带强迫。结果显示，太平洋和印度盆地都有远程信号。对于AEM的温暖阶段，ITCZ的相关位置向南，赤道大西洋上空的运动上升，导致热带其余地区的全球下沉，削弱亚洲季风，有利于中太平洋的拉尼娜条件。虽然海洋-大气耦合实验需要测试后一种假设，目前的研究表明，AEM是如何能够影响其余的热带地区，ENSO季节性可预测性的重要影响的结果。
On the frame of the AMMA-EU project, sensitivity experiments for an Atlantic Equatorial mode (AEM) which origin, development and damping resembles the observed one during the last decades of the 20th century, has been analysed in order to investigate the influence on the anomalous summer West African rainfall. Recent studies raise the matter of the AEM influence on the next Pacific ENSO episodes and also on the Indian Monsoon. This paper evaluates the response of four different atmospheric global circulation models, using the above-mentioned AEM sensitivity experiments, to study the tropical forcing associated with the Atlantic Niño mode. The results show a remote signal in both the Pacific and Indian basins. For a warm phase of the AEM the associated southward location of the ITCZ, with rising motions over the Equatorial Atlantic, leads to a global subsidence over the rest of the tropics, weakening the Asian Monsoon and favouring the La Niña conditions in the central Pacific. Although ocean–atmosphere coupled experiments are required to test the latter hypothesis, the present studies shows how the AEM is able to influence the rest of the tropics, a result with important implications on ENSO seasonal predictability.