Comparison of IRI and SMI models with IK-19 topside electron density profiles at the main trough of ionization Original Research Article

Selected 1200 topside electron density profiles from the Interkosmos-19 observations at high solar activity (1979–1982) are used for calculation of topside part of vertical electron content VEC between the F2 layer peak height, hmF2, and the height ht05 of the half peak density 0.5×NmF2. VEC is also produced with IRI and SMI models by integrating the electron density - height profile adjusted to NmF2 and hmF2 of IK-19 data. The largest departures of IRI VEC from observations occur at the main trough of ionization at high latitudes. SMI results of VEC and ht05 are more consistent with observed parameters since topside SMI Ne(h) model is based on earlier IK-19 observations. Further improvement of IRI and SMI models for the F2 layer peak height, density, and topside shape of Ne(h) profile is required.