Fig. 11From: The CHAOS-7 geomagnetic field model and observed changes in the South Atlantic AnomalySpherical harmonic spectra of the time-dependent mean square internal vector magnetic field, its Secular Variation, and Secular Acceleration at the Earth’s surface, up to spherical harmonic degree 20. Colours indicate the epoch, blue colours for 1999 to 2004, green for 2005 to 2013, red for 2014 to 2020. Top is for CHAOS-7, bottom is for reference CHAOS-6-x9Back to article page