Direct ENSO Impact on East Asian Summer Precipitation in the Developing Summer
Direct ENSO Impact on East Asian Summer Precipitation in the Developing Summer
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ENSO 对东亚夏季降水的直接影响
DOI：
10.1007/s00382-018-4545-0
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发表时间：
2018-11
期刊：
影响因子：
4.6
通讯作者：
Li Laurent
中科院分区：
文献类型：
--
作者：
Wen Na;Liu Zhengyu;Li Laurent
在ENSO发展阶段，东亚夏季降水（EASP）表现出较大的变率，与夏季衰减期有显著差异。在本研究中，我们将重点了解El Niño在观测中对发展中的夏季东亚地区降水的直接影响。发现El Niño海温异常在其发展的夏季直接从热带太平洋中东部影响EASP，受到全球其他海洋的干扰很小。相应的降水异常表现为东北和东南两个正节点和华北/华中一个负节点的三极型。三极降水响应的主要原因是东北亚El Niño-induced气旋异常和北太平洋西部反气旋异常，这是北半球副热带急流的环全球波遥相关和东亚沿海低水平经向波列的环流异常的一部分。这些环流异常是由夏季厄尔尼诺Niño产生的，有三个途径：1)进入副热带急流的热带太平洋中东部垂直运动引起的扰动激发了沿急流向东传播的绕全球波列；2)横跨赤道海洋大陆的El Niño-induced偶极子加热是东亚沿海经向波传播的主要原因；3)印度西北部El Niño-induced间接加热引发了另一次射流波导扰动，这些扰动都对东亚降水变化有贡献。进一步的论证表明，大气对El Niño直接加热和热带太平洋扰动的响应是El Niño-induced环流异常的主要贡献。对于印度西北部的El Niño间接加热，主要局限于欧亚板块的中纬度高空纬向波列响应对东亚环流异常有竞争贡献。
In the developing stage of ENSO，the East Asia summer precipitation (EASP) shows a large variability that is significantly different from that in the decaying summer. In this study, we will focus on understanding the direct El Niño impact on the precipitation over East Asia in the developing summer in the observation. It is found that in its developing summer, the El Niño sea surface temperature (SST) anomaly affects the EASP directly from the eastern-central tropical Pacific, with little interference from the rest of the global ocean. The corresponding precipitation anomaly exhibits a tri-pole pattern, with two positive nodes in northeast and southeast China, sandwiched by a negative node in northern/central China. The tri-pole precipitation response is mainly attributed to the El Niño-induced cyclonic anomaly in Northeast Asia and the anticyclonic anomaly in the western North Pacific, which are part of the circulation anomalies of a circumglobal wave teleconnection in the subtropical jet in the Northern Hemisphere and a low level meridional wave train along East Asia coast. .These circulation anomalies are generated by the summer El Niño in three pathways: 1) the vertical motion-induced perturbation over the central-eastern tropical Pacific entering into the subtropical jet excites a circumglobal wave train propagation eastward along the jet; 2) the El Niño-induced dipole heating across the equatorial Maritime Continent is mainly responsible for the meridional wave propagation along East Asia coast; 3) the El Niño-induced indirect heating over Northwest India triggers another perturbation in the jet waveguide, all contributing to the precipitation variation in East Asia. Further demonstration indicates the atmospheric response to the El Niño direct heating and perturbation over the tropical Pacific has the major contribution to the El Niño-induced circulation anomaly. As to the El Niño indirect heating over Northwset India, a zonal wave train response in the upper midlatitude which is mainly confined in the Eurasia sector makes a competing contribution to the circulation anomaly over East Asia..
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影响因子：
4.9
作者：
Arun Kumar;M. Hoerling
通讯作者：
Arun Kumar;M. Hoerling
DOI：
10.1002/joc.1159
发表时间：
2005-07
期刊：
International Journal of Climatology
影响因子：
--
作者：
Zeng‐Zhen Hu;R. Wu;J. Kinter;Song Yang
通讯作者：
Zeng‐Zhen Hu;R. Wu;J. Kinter;Song Yang
IPSL-CM5A-MR 气候模型中的主动 AMOC-NAO 耦合
影响因子：
4.6
作者：
Wen Na;Frankignoul Claude;Gastineau Guillaume
通讯作者：
Gastineau Guillaume
影响因子：
3.1
作者：
K. Trenberth;Shyh-C. Chen
通讯作者：
K. Trenberth;Shyh-C. Chen
影响因子：
4.6
作者：
Na Wen;Zhengyu Liu;Yinghui Liu
通讯作者：
Na Wen;Zhengyu Liu;Yinghui Liu