Eur. Phys. J. B 65, 547-554 (2008)
https://doi.org/10.1140/epjb/e2008-00353-0

Coexisting stochastic and coherence resonance in a mean-field dynamo model for Earth's magnetic field reversals

Forschungszentrum Dresden-Rossendorf, PO Box 510119, 01314 Dresden, Germany

Corresponding author: ^a F.Stefani@fzd.de

Received: 25 January 2008
Revised: 7 July 2008
Published online: 19 September 2008

Abstract

Using a spherically symmetric mean-field α²-dynamo model for Earth's magnetic field reversals, we show the coexistence of the noise-induced phenomena coherence resonance and stochastic resonance. Stochastic resonance was recently invoked to explain the 100 kyr periodicity in the distribution of residence times between reversals. The comparison of the resulting residence time distribution with the paleomagnetic one allows for some estimate of the effective diffusion time of the Earth's core which may be 100 kyr or slightly below rather than 200 kyr as it would result from the molecular resistivity.