Goodness of approximation of lower ionosphere parameters given by a theoretical model and by the International Reference Ionosphere (IRI)

Abstract

A theoretical model of the ionospheric D-region has been developed, which includes four positive ions (NO +, O + 2, CI + 1, CI + 2), four negative ions (O − 2, O −, CO − 3, NO − 3) and electrons. It takes into account the dependence of the rates of the basic processes on temperature, atmospheric humidity and concentrations of the minor neutral constituents. A check with experimental data (about 1000 electron density vs. height profiles, N(h)) indicates that it is able to reproduce rather accurately the seasonal and diurnal variations of N(h), and the radiowave absorption over a large frequency range. Unlike alternate empirical models it describes more accurately the fine structure of N(h)-profiles. Another advantage of the theoretical model is its ability to reproduce N(h) profiles during disturbances: WA(winter anomaly), PCA(polar cap absorption), PSE(post storm effect) after SSC, etc.