A Model of the Geodynamo

Summary The problem of the generation of the geomagnetic field by convection in the Earth's core is considered. The complete hydromagnetic problem including the Lorentz force is solved in the case of a cylindrical configuration. Because of the dominant effect of rotation this configuration incorporates the essential features of the dynamo process in the Earth's core. The results show general agreement with the known properties of geomagnetism and the Earth's core. It is found that the toroidal field in the core is of the same order of magnitude as the poloidal field. This result is consistent with the basic assumption of theory that the Lorentz force is small compared to the Coriolis force.

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