THE MEAN-FIELD DYNAMO MODEL IN GEODYNAMO
Abstract and keywords
Abstract (English):
The 2D Parker's mean-field dynamo equations with a various distributions of the #x3B1;- and #x3C9;-effects are considered. We show that smooth profiles of #x3B1; and #x3C9; can produce dipole configuration of the magnetic field with the realistic magnetic energy spectrum. We emphasize that fluctuating #x3B1;-effect leads to increase of the magnetic energy at the small scales, breaking the dipole configuration of the field. The considered geostrophic profiles of #x3B1; and #x3C9; correspond to the small-scale polarwards/equatorwards travelling waves with the small dipole field contribution. The same result is observed for the dynamic form of the #x3B1;-quenching, where two branches of the weak and strong solution coexist.

Keywords:
Earth's liquid core, turbulence, geodynamo
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