A New Generation of Geodynamo Models

Principal investigator: Dr P Livermore

Sponsor: NERC

Value: £483,422

Dates: 1st October 2009 to 31st August 2014

Summary

The geomagnetic field is generated in the Earth's core by complex motions of electrically conducting molten iron, in the so-called geodynamo mechanism. Scientific understanding has, so far, been advanced on two main fronts. (i) Forward models, taking the form of geodynamo simulations performed on
massive super-computers. (ii) Inverse models, where observations are used to image the magnetic field at the boundary of the core. Both of these techniques have severe limitations: simulations are not faithful to the conditions in the Earth's core, and inverse models cannot currently be used to probe any deeper inside the core than its boundary. Many aspects of the source of Earth’s magnetic field therefore remain a mystery.

In this fellowship, I will embark on an ambitious project that has the potential to revolutionise both of these modelling techniques and reveal the dynamics of Earth’s deep interior. I will do this by exploiting my recent mathematical developments that provide a framework for imposing the correct dynamical regime, described by a condition termed Taylor’s constraint, on the modelled Earth’s core. This allows not only the construction of a new generation of geodynamo simulations that more faithfully represent the conditions in Earth’s core, but allows the extension of current inverse techniques to probe inside the fluid core. These two complementary studies will raise the current state-of-the-art in geodynamo modelling to a new level.