Neutral winds and ion drifts in the polar ionosphere caused by convection electric fields. I

Equations of motion for ions and neutrals are solved simultaneously using a convection electric field as observed in the polar ionosphere, assuming two different latitudinal variations of ion density. It is shown that the velocity of neutral winds is generally smaller than that of ion drifts and that the direction of winds differs from that of drifts by an angle which depends upon the ion density. As may be expected from the distribution of electric field, the drift- and wind-patterns are quite different inside and outside the polar cap. It is noted that the neutral winds of electric-field origin are of the same order of magnitude as those of thermal origin. The results are discussed in comparison with observations.