Deriving winds or electric fields from ionospheric data is very important for understanding thermospheric dynamics and ionospheric electrodynamics when the direct measurements are very limited. The methods previously used need a non-wind reference height, which is difficult to be accurately determined. In this paper, we develop a method to deduce the equivalent winds including effects of both neutral winds and electric fields from measured ionospheric F-layer data. The method avoids the problem of a non-wind reference height. Ionospheric data are available from the DGS-256 Digisonde in Wuhan to provide the critical frequency of F layer and its peak height with the aid of the new version SAO-Explorer software by University for Massachusetts Lowell in American. Using this method, some preliminary characteristics of equivalent winds in the ionospheric F layer over Wuhan are deduced during the summer and winter solstices, nine days ofvery quiet magnetic conditions in Winter of the year 2000-2001. The mean pattern of the vertical equivalent winds during the winter is also calculated.Resultsshow that there are clearly day-to-day variations of vertical equivalent winds over Wuhan. Obvious morning decent features are showed both in summer solstices and winter months. The difference from summer to winter solstice daytime vertical equivalent winds is discussed. In terms of the winter northward perpendicular drifts calculated from Fejer empirical electric fields, we find that the electric vertical drift generally contributes insignificantly to the vertical equivalent winds over Wuhan. Therefore, the mean equivalent winds are composed mainly from the meridional neutral winds.
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