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Title: An approach for projecting the timing of abrupt winter Arctic sea ice loss
Abstract. Abrupt and irreversible winter Arctic sea ice loss may occur under anthropogenic warming due to the disappearance of a sea ice equilibrium at athreshold value of CO2, commonly referred to as a tipping point. Previous work has been unable to conclusively identify whether a tippingpoint in winter Arctic sea ice exists because fully coupled climate models are too computationally expensive to run to equilibrium for manyCO2 values. Here, we explore the deviation of sea ice from its equilibrium state under realistic rates of CO2 increase todemonstrate for the first time how a few time-dependent CO2 experiments can be used to predict the existence and timing of sea ice tippingpoints without running the model to steady state. This study highlights the inefficacy of using a single experiment with slow-changing CO2to discover changes in the sea ice steady state and provides a novel alternate method that can be developed for the identification of tippingpoints in realistic climate models.  more » « less
Award ID(s):
1924538
PAR ID:
10549705
Author(s) / Creator(s):
;
Publisher / Repository:
European Geosciences Union & the American Geophysical Union
Date Published:
Journal Name:
Nonlinear Processes in Geophysics
Volume:
30
Issue:
3
ISSN:
1607-7946
Page Range / eLocation ID:
299 to 309
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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