Simulating geomagnetic reversals through 2D Ising systems

Abstract

In this work 2D Ising systems were used to simulate the reversals of the Earth's magnetic field. Each spin was supposed to be a ring current in the Earth dynamo and the magnetization to be proportional to the field intensity. Given the relative success of some physical few-discs modeling of this system all the simulations were implemented in small systems. The temperature T was used as a tunning parameter. It plays the role of external perturbations. Power laws were obtained for the distribution of times between reversals. When the system size was increased the exponent of the power law asymptotically tended towards values very near -1.5, generally accepted as the right value for this phenomenon. Depending on the proximity of T and Tc the average duration of reversal period changes. In this way it is possible to establish a parallel between the model and more or less well defined periods of the reversal record. Some possible trends for future works are advanced.