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Magnetic Taylor-Proudman Constraint Explains Flows into the Tangent Cylinder

Alban Pothérat* and Kélig Aujogue

François Debray

  • Coventry University, Centre for Fluid and Complex Systems, Mile Lane, Coventry CV1 2NL, United Kingdom

  • Laboratoire National des Champs Magnétiques Intenses (LNCMI), CNRS UPR 3228, EMFL, Université Toulouse III—Paul Sabatier, Université Fédérale Toulouse Midi-Pyrénées, Institut National des Sciences Appliquées, Université Grenoble Alpes, 38042 Grenoble CEDEX, France

  • *Contact author: alban.potherat@coventry.ac.uk
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Phys. Rev. Lett. 133, 184101 – Published 31 October, 2024

DOI: https://doi.org/10.1103/PhysRevLett.133.184101

Abstract

Tangent cylinders (TCs) have shaped our understanding of planetary dynamos and liquid cores. The Taylor-Proudman constraint creates these imaginary surfaces because of planetary rotation, separating polar and equatorial regions, but cannot explain the flows meandering through them. Here, we establish and verify experimentally that magnetic fields aligned with rotation drive flows into TCs, linked to the flows along TCs by a magnetic Taylor-Proudman constraint. This constraint explains and quantifies how magnetic fields reshape rotating flows in planetary interiors and magnetorotating flows in general.

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Research News

How Earth’s Magnetic Field Influences Flows in the Planet’s Core

Published 31 October, 2024

A “Little Earth Experiment” inside a giant magnet sheds light on so-far-unexplained flow patterns in Earth’s interior.

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Article Text

Supplemental Material

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Outline

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Phys. Rev. Lett. 133, 184101– Published 31 October, 2024
  • Received 6 February 2024
  • Accepted 25 July 2024
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