Disturbances of ionospheric radio channel during magnetic storms in November–December 2023

This paper presents the results of analysis of oblique ionospheric sounding data obtained with continuous chirp signal on the subauroral paths Magadan—Irkutsk and Norilsk—Irkutsk. It specifies the interplanetary sources of magnetic storms in November–December 2023. It was established that signals propagating outside the great-circle arc and additional diffuse reflections can be found in oblique sounding ionograms in intense magnetospheric convection field. Their appearance can be related to refraction of radio waves on the polar wall of the main ionospheric trough and scattering by small-scale inhomogeneities. Connection has been revealed between variations in the maximum observed frequencies of HF radio wave propagation modes with the spatial position of the main ionospheric trough and the equatorial boundary of diffuse electron precipitation zone.