The obtained results are an example of the capability of Swarm data to generate an additional valuable dataset to properly model the topside ionosphere.
In the International Reference Ionosphere (IRI) model, the topside and bottomside electron density descriptions use a 'relative layer shape' formula depending on vertical coordinate adapting the absolute values to those at the peak (Rawer, 1988, 1990; Bilitza et al., 1993).
In fact, when having accurate and calibrated measurements, the peculiar configuration of Swarm satellites will allow to achieve new insights about the topside plasma scale height, a parameter of crucial significance to reliably model the topside profile.
For the polar regions, the varying shell height approach produced better results than the fixed shell height and compared to exponential function, Chapman function seems to be a better function to model the topside ionosphere.
For the purpose of evaluation of the IRI 2001 model, the topside sounder data obtained from the Ohzora (EXOS-C) and the Akebono (EXOS-D) satellites in the magnetic latitude range from −50° to 50° were compared with the profiles calculated from the IRI model.
An attempt has been made to model the topside electron density profile by using the data obtained by the incoherent scatter radar in Malvern (−2.34°E, 52.1°N), UK and the topside sounder data over the European PRIME region (0 35°E, 30 70°N).
