[1] This paper presents a study of thermospheric and ionospheric response to the 2008 minor sudden stratospheric warming (SSW) event. This period was characterized by low solar and geomagnetic activity. The study was performed using the Global Self-consistent Model of Thermosphere, Ionosphere, and Protonosphere (GSM TIP). Model results were compared with ionosonde data from Irkutsk, Kaliningrad, Sao Jose dos Campos, and Jicamarca. The SSW event was modeled by specifying the temperature and density perturbations at the lower boundary of the GSM TIP (80 km altitude). GSM TIP simulation allowed the reproduction of the lower thermosphere temperature disturbances (the occurrence of the quasi-wave 1 structure at 80-130 km altitude with a vertical scale of $40 km), the negative response of F2 region electron density and the positive response of electron temperature at 300 km during the 2008 minor SSW event. The main formation mechanism of the global ionospheric response is due to the disturbances (decrease) in the n(O)/n(N2) ratio. The change in zonal electric field is another important mechanism of the ionospheric response at low latitudes.

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This paper presents a consistent technique for velocity determination of meridional neutral winds from the Irkutsk incoherent scatter radar (IISR.) We calculated plasma drift velocity based on phase analysis of an autocorrelation function of an incoherent scatter signal. We also preliminary tested the described technique by determining several low‐orbit satellite velocities. Midlatitude meridional neutral winds were calculated using a “three‐beam” technique from the IISR velocity with taking into account motions due to electric fields across magnetic field lines in both meridional and zonal directions. It has been shown that an underestimated impact of the motions generated by electric fields can seriously interfere in determining wind velocities. The results obtained were compared with the modeled wind values.

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