Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 46507 10.2205/2019ES000699 ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Electron density in the polar F region ionosphere during solar minimum: modeling, radar and ionosonde observations Electron density in the polar F region ionosphere during solar minimum: modeling, radar and ionosonde observations Lukianova Renata Lukianova Renata r.lukianova@gcras.ru Kozlovsky Alexander Kozlovsky Alexander Geophysical Center of RAS and St. Petersburg State University, Institute of Earth Science ru Geophysical Center of RAS and St. Petersburg State University, Institute of Earth Science ru Sodankylä Geophysical Observatory ru Sodankylä Geophysical Observatory ru 20 1 1 16 29 10 2021 https://rjes.ru/en/nauka/article/46507/view

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.

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 Polar𝐹region ionosphere numerical modeling plasma density EISCAT radar SGOionosonde We acknowledge the staff of EISCAT for operating the facility and supplying the data. EISCAT is an international association supported by research organizations in China (CRIRP), Finland (SA), France (CNRS, till end 2006), Germany (DFG), Japan (NIPR and STEL), Norway (NFR), Sweden (VR), and the United Kingdom (STFC). The OMNI data were obtained from CDAWeb. RL acknowledges the Ministry of Science and Higher Education of the Russian Federation (budgetary funding) and the Academy of Finland (grant 310348).

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