Encyclopedia of Geomagnetism and Paleomagnetism

2007 Edition
| Editors: David Gubbins, Emilio Herrero-Bervera

Magnetohydrodynamic Waves

  • Christopher Finlay
Reference work entry
DOI: https://doi.org/10.1007/978-1-4020-4423-6_202

Introduction

Magnetohydrodynamic waves are propagating disturbances found in electrically conducting fluids permeated by magnetic fields where magnetic tension provides a restoring force on fluid parcels moving across field lines. The role played by magnetohydrodynamic waves, transporting disturbances in the flow and magnetic field and connecting disparate regions of the fluid, is crucial to our understanding of hydromagnetic systems. Magnetohydrodynamic waves in the Earth's liquid iron outer core have been proposed as the origin of changes of the Earth's magnetic field taking place on timescales of decades to centuries, and are thus of interest to both geomagnetists and paleomagnetists.

In the Earth's outer core, in addition to the magnetic forces acting on the electrically conducting fluid, we must also consider Coriolis forces resulting from planetary rotation, buoyancy forces due to gravity acting on density gradients and the constraints placed on flow by spherical shell geometry....

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© Springer-Verlag 2007

Authors and Affiliations

  • Christopher Finlay

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