Panels 1 (a) and 2 (a) show foF2 obtained from NeQuick model (blue line), assimilation results (red line), and ionosonde stations (black dots) at JJ433 and OK426, respectively. Panels 1 (b) and 2 (b) present the magnitudes of the differences between foF2 obtained from NeQuick model (blue bars) and assismilation results (red bars) and that observed at ionosonde stations at JJ433 and OK426, respectively.