Fig. 3From: Forecasting yearly geomagnetic variation through sequential estimation of core flow and magnetic diffusionPower spectra of the RMS error for CHAOS-6 flow-only hindcasts at Earth’s surface over 2010–2015, computed with a the 2001.0–2010.0 and b 2009.0–2010.0 model fitting periods for several \(L_u\). Shown for comparison are the error spectra for IGRF-11 and a CHAOS-3 forecastBack to article page