A test of IRI lower ionosphere models by comparison with radio propagation data

Abstract

Data on noon and night-time radio wave absorption (oblique and vertical incidence) in the frequency range 50–2614 kHz, obtained in long-term observational programmes in Central Europe, are compared with the corresponding values calculated from profiles deduced from rocket observations and proposed by Rawer (1977a) in view of the International Reference Ionosphere, and the CIRA 1972 neutral pressure profile for deducing collision frequencies. At this computation full-wave and phase-integral methods were used. Considerable discrepancies between calculated and observed absolute absorption values and their seasonal and solar cycle variations were found. We suggest a revision of Rawer's (1977a) D- region model parameters so as to provide a more satisfactory agreement with the above measurements.