Dynamical constraints on the leading-order ‘QG-MAC’ force balance expected in Earth’s core have been integrated into a geomagnetic inverse problem framwork, enabling a dynamically-consistent estimate of the fluid flow, density anomaly and magnetic field near the core surface from recent geomagnetic data. The technique also quantifies the consistency of this ‘QG-MAC’ balance with geomagnetic data. 

Aubert, J.: Recent geomagnetic variations and the force balance in Earth’s core, Geophys. J. Int. 221, 378-393, 2020, doi: 10.1093/gji/ggaa007.