Southern Hemispheric jet swing linked to Arctic stratospheric polar vortex

作者：Fei Xie, Xuan Ma, Yanjie Li, Jianping Li, Xiaosong Chen, Wenshou Tian, Cheng Sun, Mian Xu, Jiankai Zhang, Ke Gui, Ruiqiang Ding, Yan Xia, Yingli Niu · 发表于：Environmental Research Letters · 年份：2024 · DOI：10.1088/1748-9326/ad3460 · 被引用次数：7 · 研究领域：Atmospheric Ozone and Climate、Arctic and Antarctic ice dynamics、Climate variability and models

Abstract Our study reframes our understanding of stratosphere–troposphere interactions, traditionally thought to be confined within individual hemispheres, by introducing a novel cross-hemispheric link. We demonstrate that strong boreal winter Arctic stratospheric polar vortex (APV) boosts the transmission of upper tropospheric waves from Northern Hemisphere’s mid-high latitudes to the equator. Facilitated by the tropical central and eastern Pacific’s ‘westerly bridge’, these waves reach Southern Hemisphere’s mid-high latitudes. The entire process shows a ‘semicircular road’. Waves reaching the Southern Hemisphere affect the circulation through wave-flow interaction, causing a southward swing of the Southern Hemispheric westerly jet center. This displacement weakens the subtropical jet and strengthens the polar jet, resulting in increased subtropical precipitation and decreased mid-latitude precipitation in the Southern Hemisphere during austral summer. Correspondingly, a weak APV may lead to the opposite result. Our findings underscore APV’s broader impact on the tropospheric atmosphere, extending beyond prior knowledge.