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The stratospheric pathway for Arctic impacts on midlatitude climate
Author(s) -
Nakamura Tetsu,
Yamazaki Koji,
Iwamoto Katsushi,
Honda Meiji,
Miyoshi Yasunobu,
Ogawa Yasunobu,
Tomikawa Yoshihiro,
Ukita Jinro
Publication year - 2016
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2016gl068330
Subject(s) - stratosphere , middle latitudes , arctic oscillation , polar vortex , climatology , sudden stratospheric warming , sea ice , arctic geoengineering , arctic , arctic sea ice decline , atmospheric sciences , environmental science , northern hemisphere , arctic ice pack , troposphere , arctic dipole anomaly , geology , oceanography , drift ice
Recent evidence from both observations and model simulations suggests that an Arctic sea ice reduction tends to cause a negative Arctic Oscillation (AO) phase with severe winter weather in the Northern Hemisphere, which is often preceded by weakening of the stratospheric polar vortex. Although this evidence hints at a stratospheric involvement in the Arctic‐midlatitude climate linkage, the exact role of the stratosphere remains elusive. Here we show that tropospheric AO response to the Arctic sea ice reduction largely disappears when suppressing the stratospheric wave mean flow interactions in numerical experiments. The results confirm a crucial role of the stratosphere in the sea ice impacts on the midlatitudes by coupling between the stratospheric polar vortex and planetary‐scale waves. Those results and consistency with observation‐based evidence suggest that a recent Arctic sea ice loss is linked to midlatitudes extreme weather events associated with the negative AO phase.