HIGH LATITUDE FIELD-ALIGNED CURRENT SOURCES AND INDUCED ELECTRIC-FIELDS

Using a simple, planar model of the high-altitude ionosphere with an enhanced conductivity auroral ring, the electric potential for a pair of field-aligned current sheets inferred from observations is computed. The relationship of various characteristics of the electric potential pattern to features of the field-aligned current distribution are elucidated in the context of a generalized field-aligned current Fourier analysis. On the basis of the analysis and observations to date it is concluded that boundary layer dynamo action is the prevalent mechanism in the solar wind/magnetosphere/ionosphere interaction.