Fig. 4.From: Rapid modelling of the large-scale magnetospheric field from Swarm satellite dataThe Magnitude Squared Coherence between the (external) coefficients from the FTMM and the TDS-1 reference model for all frequencies (top) and for periods greater than two days (bottom). The coherency is very good for low frequencies but falls off sharply for periods less than about 5 hours. Dips at 24 and 12 hours are likely due to ionospheric field contamination.Back to article page