An approach for projecting the timing of abrupt winter Arctic sea ice loss

Abrupt and irreversible winter Arctic sea-ice loss may occur under anthropogenic warming due to the collapse of a sea-ice equilibrium at a threshold value of CO2, commonly referred to as a tipping point. Previous work has been unable to conclusively identify whether a tipping point in Arctic sea ice...

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Bibliographic Details
Main Authors: Hankel, Camille, Tziperman, Eli
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2022
Subjects:
Online Access:https://doi.org/10.5194/egusphere-2022-1469
https://noa.gwlb.de/receive/cop_mods_00064151
https://egusphere.copernicus.org/preprints/egusphere-2022-1469/egusphere-2022-1469.pdf
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Summary:Abrupt and irreversible winter Arctic sea-ice loss may occur under anthropogenic warming due to the collapse of a sea-ice equilibrium at a threshold value of CO2, commonly referred to as a tipping point. Previous work has been unable to conclusively identify whether a tipping point in Arctic sea ice exists because fully-coupled climate models are too computationally expensive to run to equilibrium for many CO2 values. Here, we explore the deviation of sea ice from its equilibrium state under realistic rates of CO2 increase to demonstrate how a few time-dependent CO2 experiments can be used to predict the existence and timing of sea-ice tipping points without running the model to steady-state. This study highlights the inefficacy of using a single experiment with slow-changing CO2 to discover changes in the sea-ice steady-state, and provides an alternate method that can be developed for the identification of tipping points in realistic climate models.