ИСТИНА

The paper shows the effect on the electron density in the F2 layer of the ionosphere of the long-period drift (1990–2013) of the north magnetic pole (NMP) through the associated displacements of the auroral oval, the region of precipitation of energy particles and field aligned current zones. The drift impact assessment was performed in the semi-empirical version UAM TM of the UAM model for the subauroral and auroral zones of the northern hemisphere. The calculations were compared with the data of the vertical radio sounding in 2013 at the observatories in Voejkovo, Sodankylä, Tromsø and with the IRI-Plas model. In Voejkovo, sounding was performed by a digital ionosonde CADI, in Sodankylä by an ionosonde Alpha-wolf, in Tromsø - DIGISONDE. Calculations for the IRI-Plas model are corrected by GPRS data, therefore, are used as averaged observational data. In the calculations in the UAM TM model, the shift of the magnetic pole was taken into account as a change in the connection between the geographic and geomagnetic coordinates of the polar cap, the precipitation zone, and the field aligned currents. For all calculations, the position of the polar cap and the corresponding zones of precipitation and field aligned currents were equally calculated in the grid of dipole coordinates from the magnetic pole, but the geographical coordinates of these zones varied depending on the geographical position of the magnetic pole. The results showed that the entire pattern of critical frequencies of the northern hemisphere layer F2 (foF2) is depended on the NMP drift. The diurnal foF2 graphs were calculated for the positions of the observatories. Forms of these graphs of foF2 observations in 2013 and graphs for the IRI-Plas model are better agreed with the UAM TM calculated graphs for the NMP in 2013 than for the NMP in 1990. For the auroral zone, the foF2 values for the NMP in 2013 are lower than the observed ones, and for the subauroral zone, with the good agreement in the morning and daytime, the foF2 model values are lower in the evening and higher at night. Specifying the shape of the precipitation zones and field aligned currents can improve the agreement of the model and real data. It is concluded that a significant drift of the NMP for the period 1990-2013 had a strong effect on the electron concentration profile in the northern hemisphere. The effect was especially evident in the calculations for the subauroral zone in the evening and at night, in the auroral zone - during the day.