Auroral Activity Effects on Mesospheric Neutral Winds

摘要

In June and October, 1981 and February, 1982 experiments were carried out with the Chatanika Incoherent Scatter radar and the Poker Flat MST radar operating simultaneously for the purpose of comparing the characteristics of the neutral wind in the thermosphere and the mesosphere. The incoherent scatter observations were made with the radar beam oriented parallel to the direction of the local magnetic field to minimize the effects of magnetospheric convection electric fields on the ion velocities, which can then be interpreted as the field-aligned component of the neutral velocity. About 100 hours of incoherent scatter data were accumulated during about 15 local nighttime sessions. This experiment and examples of the data are described in Appendix A. The example in Figure 2 of Appendix A gives an overview of these observations. In order to establish a stronger case for or against auroral activity effects on the mesospheric winds, we put aside the requirement for simultaneous thermospheric measurements to instead concentrate on analyses of the continuous 1980-82 summer MST radar data base. For this purpose, the magnetometer at College was used as the local auroral activity monitor.