Numerical Models in the Theory of Geomagnetism

Abstract

The potential of numerical models for the theoretical understanding of the dynamics of the Earth’s core and the origin of the geomagnetic field is discussed. Some initial results of the analysis of convection driven dynamos in rotating spherical fluid shells are presented. As the parameter regime of the problem is more fully explored, the numerical simulation of processes such as geomagnetic secular variation and geomagnetic reversals becomes feasible. Because the physical conditions of the Earth’s core are not sufficiently well understood, the interaction between numerical modelling and geomagnetic observations will become increasingly important. The decade fluctuations in the length of the day may provide additional constraints on models of the geodynamo if the process of electromagnetic core-mantle coupling is sufficiently strong.