Instability of the halocline at the North Pole

Christian Puntini

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arXiv · 2509.21378

Instability of the halocline at the North Pole

Christian Puntini

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Abstract

In this paper we address the issue of stability for the near-inertial Pollard waves, as a model for the halocline in the region of the Arctic Ocean centered around the North Pole, derived in Puntini (2026). Adopting the short-wavelength instability approach, the stability of such flows reduces to study the stability of a system of ODEs along fluid trajectories, leading to the result that, when the steepness of the near-inertial Pollard waves exceeds a specific threshold, those waves are linearly unstable. The explicit dispersion relation of the model allows to easily compute such threshold, knowing the physical properties of the water column.

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Christian Puntini. 2025-09-23. Instability of the halocline at the North Pole. https://arxiv.org/abs/2509.21378

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