We use measurements of the ionospheric electron density (Ne" role="presentation" style="position: relative;">NeNeN_e) obtained by the EISCAT Svalbard radar (ESR) and the Sodankyla Geophysical Observatory (SGO) ionosonde for comparison with the Ne" role="presentation" style="position: relative;">NeNeN_e distribution predicted by a numerical model of the polar F" role="presentation" style="position: relative;">FFF region ionosphere. The model enables representing the main large-scale ionospheric irregularities, which are primarily controlled by the interplanetary magnetic field, particle precipitation, solar zenith angle and properties of the neutral atmosphere. The analysis utilizes the data collected in March, July and January under very quiet space weather conditions, when the radar operated almost continuously during International Polar Year. The main ionospheric parameters (magnitude and height of the F2" role="presentation" style="position: relative;">F2F2F2 layer peak density) are inferred from the Ne" role="presentation" style="position: relative;">NeNeN_e composites constructed for each local time hour. The results indicate that the modeled Ne" role="presentation" style="position: relative;">NeNeN_e distributions are in a reasonable agreement with the experimental data. However, the modeled altitude and peak density systematically exceed, by about 10%, the observed values.
Polar𝐹region ionosphere, numerical modeling, plasma density, EISCAT radar, SGOionosonde
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