Indian Ocean Dipole and ENSO’s mechanistic importance in modulating the ensuing-summer precipitation over Eastern China
Indian Ocean Dipole and ENSO’s mechanistic importance in modulating the ensuing-summer precipitation over Eastern China
复制标题
DOI：
10.1038/s41612-022-00271-5
复制
发表时间：
2022-06
影响因子：
9
通讯作者：
Yue Zhang;Wen Zhou;Xin Wang;Sheng Chen;Jiepeng Chen;Shanshan Li
中科院分区：
文献类型：
--
作者：
Yue Zhang;Wen Zhou;Xin Wang;Sheng Chen;Jiepeng Chen;Shanshan Li
2020年夏季，中国东部地区异常潮湿，这与印度洋偶极子（IOD）的潜在延迟效应有关。需要额外的知识来提高我们对这种效应的详细机制的理解。在这项研究中，我们比较了 IOD 和厄尔尼诺南方涛动 (ENSO) 对夏季降水的延迟影响相关的物理过程。偏相关和综合分析表明，ENSO主要调节长江流域降水，而IOD则有利于更北地区的降水。 IOD和ENSO都可以在接下来的夏季刺激北太平洋西部（WNP）的反气旋环流，但由于不同的海面温度（SST）演化过程而具有不同的空间分布。 IOD 类似地伴随着印度洋的变暖信号，即所谓的“电容器”效应，但其位置比 ENSO 相关的位置更靠近澳大利亚。 IOD还在接下来的夏季刺激了赤道太平洋显着的海温冷却异常，共同导致了西太平洋国家公园上空的异常反气旋。数值实验证实，印度洋“电容器”和赤道太平洋变冷的综合作用可以在西太平洋国家公园上空产生沿经向分布更广泛的异常反气旋。
Eastern China was extremely wet in summer 2020, which is found to be related to the potential delayed effects of the Indian Ocean Dipole (IOD). Additional knowledge is warranted to improve our understanding of detailed mechanisms of such an effect. In this study, we compared physical processes associated with delayed effects of the IOD and El Niño–Southern Oscillation (ENSO) on summer precipitation. Partial correlation and composite analysis reveal that ENSO modulates precipitation mainly over the Yangtze River Valley, whereas IOD benefits precipitation farther north. Both IOD and ENSO can stimulate anticyclonic circulation over the western North Pacific (WNP) in the ensuing summer but with different spatial distributions related to the different sea surface temperature (SST) evolution processes. IOD is similarly followed by warming signals in the Indian Ocean, known as the “capacitor” effect, but the location is closer to Australia than that associated with ENSO. IOD also stimulates significant SST cooling anomalies over the equatorial Pacific during the ensuing summer, jointly contributing to the anomalous anticyclone over WNP. Numerical experiments confirm that combined effects of the Indian Ocean “capacitor” and equatorial Pacific cooling can generate an anomalous anticyclone with wider distribution in the meridional direction over WNP.