Robust Enhancement of Tropical Convective Activity by the 2019 Antarctic Sudden Stratospheric Warming
Robust Enhancement of Tropical Convective Activity by the 2019 Antarctic Sudden Stratospheric Warming
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DOI：
10.1029/2020gl088743
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发表时间：
2020-08
影响因子：
5.2
通讯作者：
S. Noguchi;Y. Kuroda;K. Kodera;S. Watanabe
中科院分区：
文献类型：
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作者：
S. Noguchi;Y. Kuroda;K. Kodera;S. Watanabe
通过进行一系列集合预报实验，研究了热带对流层对 2019 年 9 月南极洲上空发生的突然平流层变暖 (SSW) 事件的响应。正常预报与部分微调预报（其平流层环流仅限于重新分析）之间的比较检查揭示了热带北部/南部对流活动（上升流/下降流）的显着增强/抑制。哈德利环流的这种加速是由对流层上部和平流层下部的热结构变化造成的。布鲁尔-多布森环流增强引起的热带降温破坏了那里的环境稳定并刺激了深层积云对流。在这种情况下，亚洲季风区南部地区尤为敏感。尽管触发响应的细节取决于所采用的积云参数化方案，但通过 SSW 的对流上升流的增强趋势是稳健的。
Tropical tropospheric responses to a sudden stratospheric warming (SSW) event that occurred over Antarctica in September 2019 have been investigated by conducting a series of ensemble forecast experiments. Comparative examinations between the normal forecast and the partially nudged forecast, whose stratospheric circulation is constrained to a reanalysis, reveal a significant enhancement/suppression in the convective activity (upwelling/downwelling) over the northern/southern part of the tropics. Such an acceleration of the Hadley circulation is set up by thermal structural changes in the upper troposphere and lower stratosphere. The tropical cooling caused by the enhanced Brewer‐Dobson circulation destabilizes the environment there and stimulates deep cumulus convections. In this case, the southern area of the Asian monsoon region is particularly sensitive. Although details of the triggered response depend on the adopted cumulus parameterization scheme, a boosting tendency of the convective upwelling via the SSW is robust.