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arXiv · 2210.16151

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

Camille Hankel·Eli Tziperman
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Abstract

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 CO$_2$, 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 CO$_2$ values. Here, we explore the deviation of sea ice from its equilibrium state under realistic rates of CO$_2$ increase to demonstrate how a few time-dependent CO$_2$ 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 CO$_2$ 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.

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Camille Hankel, Eli Tziperman. 2022-12-20. An approach for projecting the timing of abrupt winter Arctic sea ice loss. https://arxiv.org/abs/2210.16151

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