Numerical Modeling of the High-Latitude F-Layer Anomalies

Abstract

The results of a detailed numerical study of the behaviour of the convective polar ionosphere are presented. The developed theoretical model produces three-dimensional distribution of electron density, electron and ion temperature. The effects of auroral particle precipitation on the density and temperature structures are studied for winter and low solar activity conditions. The high-latitude ionospheric features, such as ‘the tongue of ionization’, ‘the main trough’, ‘the polar ionization peak’, ‘the auroral ionization peak’, ‘the high-latitude ionization hole’, ‘the tongue of electron temperature’, ‘the high latitude minima of electron temperature’, and ‘the ion temperature hot spot’ are obtained from calculations.Numerically obtained results are used for determining the HF propagation paths in the polar ionosphere. The effects of ionospheric irregularities on high frequency ionospheric radio waves are investigated by using a three-dimensional ray-tracing computer program. Ray-path trajectories are presented for different values of the elevation angle of transmission. From our study, it was found that large-scale irregularity structures of the high-latitude ionosphere, in the presence of the earth’s magnetic field, significantly affect high frequency radio wave propagation.