Numerical modeling of the polar ionosphere parameters

An overview of the three numerical models for calculating the electrodynamic parameters of the Earth's high-latitude ionosphere is presented. The model of the global distribution of the ionospheric electric potential, constructed on the basis of the solution of the boundary value problem on the spreading of ionospheric currents, makes it possible to calculate the trajectories of convection of the ionospheric plasma in the northern and southern hemispheres. The model of the high-latitude ionosphere allows calculating the three-dimensional structure of the electron density in the altitude range of 120–500 km under various helio-geophysical conditions. Importance of the electric fields of magnetospheric origin is stressed. Concentration of the main ionospheric ions is determined by the solution of the photochemical balance equation and the convective-diffusion equation along the trajectory of the plasma tube convection, taking into account the parameters of the thermosphere. A methodology and algorithms for calculating the distribution of magnetic field over the ionosphere, which is created by electric currents of magnetospheric origin, are developed. The model is based on the solution of the equation for the vector magnetic potential and makes it possible to calculate a two-dimensional picture of the magnetic variations.