A reversed plasma convection flow in the polar ionosphere observed with EISCAT radar

An abnormal anti-sunward intense flow of plasma convection is observed by E ISCAT radar in the high-latitude ionosphere near the polar cap boundary. It occurred at morning sector of MLT under conditions of southward IMF B-z du ring the recovery phase of a moderate magnetic storm. A synthetic analysis of radar data and in-situ satellite observations is made in combination wit h a tracing of magnetic field lines by means of magnetospheric field model on this event. It is evidently indicated that the abnormal reversed westwar d flow of plasma convection and the features of the plasma structure and pr operty are probably the ionospheric signatures of magnetic reconnection tak ing place at the dayside magnetopause.