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Title: Impact of the Pacific sector sea ice loss on the sudden stratospheric warming characteristics
Abstract The atmospheric response to Arctic sea ice loss remains a subject of much debate. Most studies have focused on the sea ice retreat in the Barents-Kara Seas and its troposphere-stratosphere influence. Here, we investigate the impact of large sea ice loss over the Chukchi-Bering Seas on the sudden stratospheric warming (SSW) phenomenon during the easterly phase of the Quasi-Biennial Oscillation through idealized large-ensemble experiments based on a global atmospheric model with a well-resolved stratosphere. Although culminating in autumn, the prescribed sea ice loss induces near-surface warming that persists into winter and deepens as the SSW develops. The resulting temperature contrasts foster a deep cyclonic circulation over the North Pacific, which elicits a strong upward wavenumber-2 activity into the stratosphere, reinforcing the climatological planetary wave pattern. While not affecting the SSW occurrence frequency, the amplified wave forcing in the stratosphere significantly increases the SSW duration and intensity, enhancing cold air outbreaks over the continents afterward.  more » « less
Award ID(s):
1642232
PAR ID:
10432450
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
npj Climate and Atmospheric Science
Volume:
5
Issue:
1
ISSN:
2397-3722
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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