Nonlinearity in Parker’s dynamo model

Category: 15-2
M.Yu. Reshetnyak


UDC 550.383



M.Yu. Reshetnyak


Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russia


Abstract. The various mechanisms of the a effect quenching by the magnetic field in Parker’s dynamo model in the liquid Earth’s core are considered. We show that random fluctuations of the a effect, which causes chaotic reversals of the geomagnetic field, lead to increase of the magnetic energy at the small scales. To provide reversals due to fluctuations, the total magnetic energy should increase in one order relative to the state without fluctuations.


Keywords: geodynamo, kinetic helicity, differential rotation, reversals.



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