Fig. 13From: Machine learning-based calibration of the GOCE satellite platform magnetometersMain field (left) and secular variation (right) energy spectra at the Earth’s surface in 2014.0. Spectra of the mean (solid lines), standard deviation (dashed lines) and difference with the Kalmag model (circles) for model G (thick lines and symbols) and model C (thin lines and symbols)Back to article page