Top panel: α_mag used for the merged magnetic field (orange) compared to Eq. (3) (black). Bottom panel: MAG noise (red), SCM noise (black), and computed (blue) and observed (orange) merged noise for the X_srf component (worst case for SCM). Note that at high frequencies the merged magnetic field has a noise value that 14% above the one from SCM data alone because of the increase in SCM amplitudes to match MAG amplitudes at low frequencies.