Abstract
A magnetic field suppresses hydrodynamic turbulence. This leads to a weakening of a large-scale magnetic field generation by small-scale flows and, simultaneously, to a decrease in ohmic dissipation. It is shown that a decrease in dissipation is important for the process of changing the polarity of the geomagnetic dipole: both the frequency of reversals increases and their fine structure changes. In particular, the time for the decrease in the dipole strength becomes comparable with the time for its recovery after the reversal. This is consistent with the results of 3D modeling and most paleomagnetic observations.
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The work is carried out within the State Assignment of the Schmidt Institute of Physics of the Earth, Russian Academy of Sciences.
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Translated by E. Oborin
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Reshetnyak, M.Y. Magnetic Field Suppression of Turbulence during Reversals. Moscow Univ. Phys. 77, 535–541 (2022). https://doi.org/10.3103/S0027134922030092
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DOI: https://doi.org/10.3103/S0027134922030092