Weakening of the stratospheric polar vortex by Arctic sea-ice loss

• Published in: Nature Communications
• Main Authors: Kim, BM, Son, SW, Min, SK, Jeong, JH, Kim, SJ, Zhang, XD, Shim, T, Yoon, JH
• Other Authors: 환경공학부, 11198091
• Format: Article in Journal/Newspaper
• Language: English
• Published: NATURE 2014
• Subjects: ATMOSPHERIC RESPONSE; MODEL; VARIABILITY; EVENTS; IMPACT; LINK; Arctic; Sea ice
• Online Access: https://oasis.postech.ac.kr/handle/2014.oak/13082; https://doi.org/10.1038/NCOMMS5646

Successive cold winters of severely low temperatures in recent years have had critical social and economic impacts on the mid-latitude continents in the Northern Hemisphere. Although these cold winters are thought to be partly driven by dramatic losses of Arctic sea-ice, the mechanism that links sea-ice loss to cold winters remains a subject of debate. Here, by conducting observational analyses and model experiments, we show how Arctic sea-ice loss and cold winters in extra-polar regions are dynamically connected through the polar stratosphere. We find that decreased sea-ice cover during early winter months (November-December), especially over the Barents-Kara seas, enhances the upward propagation of planetary-scale waves with wavenumbers of 1 and 2, subsequently weakening the stratospheric polar vortex in mid-winter (January-February). The weakened polar vortex preferentially induces a negative phase of Arctic Oscillation at the surface, resulting in low temperatures in mid-latitudes. open 1 1 167 174 Y scie scopus