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arXiv · 2510.12525

Chaotic variability in a model of coupled ice streams

Kolja Kypke·Peter Ashwin·Peter Ditlevsen
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Abstract

Regions of fast-flowing ice in ice sheets, known as ice streams, have been theorized to be able to exhibit build-up/surge oscillatory variability due to thermomechanical coupling at the base of the ice. A simple model of three coupled ice streams is constructed to replicate the spatial configuration of a single ice stream being bisected into two termini. The model is constructed to mimic existing branching ice streams in northern Greenland. This model is shown to exhibit both steady-flow and build-up/surge oscillations. Further, the variability can be chaotic due to the nonlinear coupling of three incommensurate frequencies. This provides a mode of chaotic internal variability for ice sheets that contain these types of ice streams.

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Kolja Kypke, Peter Ashwin, Peter Ditlevsen. 2025-10-14. Chaotic variability in a model of coupled ice streams. https://arxiv.org/abs/2510.12525

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