COMPARISON OF MODEL HIGH-LATITUDE ELECTRON DENSITIES WITH MILLSTONE HILL OBSERVATIONS.

Abstract

Model predictions of the diurnal variations of plasma convection velocities and electron densities in the high-latitude ionosphere were compared with Millstone Hill incoherent scatter radar observations for an equinox day on which there was moderate magnetic activity. The model was able to reproduce two features quite accurately. Except for a discrete arc region in the dusk sector, the enhanced electron densities in the auroral zone were adequately described by the average precipitation fluxes used in the model. The observed plasma drift velocities were consistent with a two-cell, asymmetric convection pattern with enhanced flow in the dusk sector. Outside the polar cap, the fall-off of the magnetospheric potential with latitude was proportional to the inverse of the sine of colatitude to the fourth power.