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The equipment and methodical characteristics of determining the vertical component of the ionospheric plasma motion velocity Vz based on an incoherent scatter radar of Institute of Ionosphere, National Academy of Sciences and Ministry of Education and Science of Ukraine (Kharkiv), which is the only radar of such type in Central Europe, are described. Based on the radar data, the patterns of altitude and diurnal variations in Vz near the maximum of solar cycle 24 for the typical geophysical conditions (around the summer and winter solstices, the spring and fall equinoxes) at low geomagnetic activity and the specifics of these changes during ionospheric storms are presented. The results of modeling of the dynamic processes in ionospheric plasma under the conditions of the undisturbed ionosphere, including the determination of altitudetime variations in the thermospheric wind velocity, are presented. It has been established that this velocity can significantly differ from the thermospheric wind velocity calculated by the known empirical global models. This difference is likely related to the regional features of thermospheric wind that are not shown in the global models.

The observation results of the effects in the geospace plasma during a partially (magnitude ∼0.42) solar eclipse are presented. The experimental data were obtained with an incoherent scatter radar of the Institute of the Ionosphere (near Kharkov). During the eclipse, the density at the F2 layer maximum decreased by 32%, the foF2 critical frequency decreased by 17.5%, and the altitude of the F2 layer maximum increased insignificantly. At altitudes of 290–680 km, the electron density decreased by ∼25%. During the eclipse, the electron and ion temperature decreased by 70–180 and 0–140 K, respectively, at altitudes of 190–490 km. Near the eclipse main phase, the plasma velocity vertical component decreased by 10–45 m/s at altitudes of 200–470 km, respectively. At the time of the eclipse main phase, the hydrogen ion fractional density increased by 50% as compared to the reference day at altitudes of 450–650 km.