Fig. 2From: Inter-hemispheric imaging of the ionosphere with the upgraded IRI-Plas model during the space weather stormsOpposite relative changes of the F2-layer critical frequency versus topside scale height during storms at solar maximum (dots, 2000) and solar minimum (crosses, 2006) and the analytical model (dashed line—2000, thin solid line—2006) in a bi-logarithmic frame.Back to article page