Research

Threshold-based predictions of the Earth’s axial magnetic dipole field

We study predictions of reversals of Earth’s axial magnetic dipole field that are based solely on the dipole’s intensity. The prediction strategy is, roughly, that once the dipole intensity drops below a threshold, then the field will continue to decrease and a reversal (or a major excursion) will occur. Below you will find a collection of slides discussing this study along with a short video introducing them.

Data assimilation for decadal-scale geomagnetic forecasting

There has been growing interest in using data assimilation (DA) with numerical geodynamo models to better understand the processes of the Earth's deep interior and improve decadal-scale forecasting of the magnetic field. There remain several fundamental questions regarding the application of DA in geomagnetism. Progress in DA in other sciences is in part attributable to the availability of relevant simplified models, such as the Lorenz models, that can be used to test the various aspects of a DA system. With the success of this approach in mind, we have created a new, simplified model that couples a chaotic flow to an induction equation. This model is designed so that computations are orders of magnitude less expensive than computations with a 3D geodynamo model. For this reason, the simplified model can be used as a computationally effective test-bed for approaches to geomagnetic DA. Below is a presentation on this work from the 2020 SIAM-Mathematics of Planet Earth conference. An article discussing this presentation can be found here.