Toroidal flux oscillation as possible cause of geomagnetic excursions and reversals |
| |
Authors: | F.H. Busse R.D. Simitev |
| |
Affiliation: | aInstitute of Physics, University of Bayreuth, D-95440 Bayreuth, Germany;bDepartment of Mathematics, University of Glasgow, G12 8QW Glasgow, UK |
| |
Abstract: | It is proposed that convection driven dynamos operating in planetary cores could be oscillatory even when the oscillations are not directly noticeable from the outside. Examples of dynamo simulations are pointed out that exhibit oscillations in the structure of the azimuthally averaged toroidal magnetic flux while the mean poloidal field shows only variations in its amplitude. In the case of the geomagnetic field, global excursions may be associated with these oscillations. Long period dynamo simulations indicate that the oscillations may cause reversals once in a while. No special attempt has been made to use most realistic parameter values. Nevertheless some similarities between the simulations and the paleomagnetic record can be pointed out. |
| |
Keywords: | Geodynamo Excursions Reversal Dynamo oscillations |
本文献已被 ScienceDirect 等数据库收录! |
|