Geomagnetism and the dynamo: where do we stand?

Emmanuel Dormy; Jean-Louis Le Mouël

doi:10.1016/j.crhy.2008.07.003

The dynamo effect/L'effet dynamo

Geomagnetism and the dynamo: where do we stand?
[Le point sur le géomagnétisme et la dynamo]

Emmanuel Dormy ^1,² ; Jean-Louis Le Mouël ¹

¹ Institut de physique du globe de Paris, 4, place Jussieu, 75005 Paris, France
² MAG-LRA, Département de physique, 24, rue Lhomond, 75005 Paris, France

Comptes Rendus. Physique, Volume 9 (2008) no. 7, pp. 711-720.

Résumé
Abstract

Nous passons en revue les développements récents qu'ont connus à la fois l'observation du champ magnétique terrestre principal (de l'échelle du temps de la vie humaine à celle des temps géologiques) et la modélisation de ses sources, recourant au calcul numérique et à l'expérience. Nous rapprochons ces avancées et montrons comment, lorsqu'on les combine, elles peuvent permettre de mieux comprendre la dynamique du noyau fluide terrestre. Nous supposons une connaissance préalable de la théorie dynamo, mais pas du géomagnétisme.

We review recent developments both in the observation of the Earth's magnetic field (from the short, human life timescale, to the long, geological timescale) and in the modelling of its origin (using the numerical or the experimental approach). We attempt a confrontation of these results, coming from very different fields, and show how, when combined, they can yield a better understanding of the Earth's core dynamics. We assume prior knowledge of dynamo theory, but not of geophysics.

Publié le : 2008-09-01

DOI : 10.1016/j.crhy.2008.07.003

Keywords: Dynamo, Magnetohydrodynamics, Turbulence
Mot clés : Dynamo, Magnétohydrodynamique, Turbulence

Affiliations des auteurs :

Emmanuel Dormy ^{1, 2} ; Jean-Louis Le Mouël ¹

¹ Institut de physique du globe de Paris, 4, place Jussieu, 75005 Paris, France
² MAG-LRA, Département de physique, 24, rue Lhomond, 75005 Paris, France

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Emmanuel Dormy; Jean-Louis Le Mouël. Geomagnetism and the dynamo: where do we stand?. Comptes Rendus. Physique, Volume 9 (2008) no. 7, pp. 711-720. doi : 10.1016/j.crhy.2008.07.003. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2008.07.003/

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