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The modification of turbulent thermal wind balance by non-traditional effects

Published online by Cambridge University Press:  25 August 2021

Matthew N. Crowe Open the ORCID record for Matthew N. Crowe [Opens in a new window]
Matthew N. Crowe*
Affiliation:
Department of Mathematics, University College London, London WC1E 6BT, UK
*
†Email address for correspondence: m.crowe@ucl.ac.uk
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Abstract

The meridional component of the earth's rotation is often neglected in geophysical contexts. This is referred to as the ‘traditional approximation’ and is justified by the typically small vertical velocity and aspect ratio of such problems. Ocean fronts are regions of strong horizontal buoyancy gradient and are associated with strong vertical transport of tracers and nutrients. Given these comparatively large vertical velocities, non-traditional rotation may play a role in governing frontal dynamics. Here the effects of non-traditional rotation on a front in turbulent thermal wind balance are considered using an asymptotic approach. Solutions are presented for a general horizontal buoyancy profile and examined in the simple case of a straight front. Non-traditional effects are found to depend strongly on the direction of the front and may lead to the generation of jets and the modification of the frontal circulation and vertical transport.

JFM classification

Geophysical and Geological Flows: Ocean circulation Geophysical and Geological Flows: Rotating flows
Type
JFM Papers
Information
Journal of Fluid Mechanics , Volume 925 , 25 October 2021 , A17
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Copyright
© The Author(s), 2021. Published by Cambridge University Press

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