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Summary
Schematic diagram of the electric-current pattern in the ionosphere driven by diurnal heating from the Sun. Note that the current is concentrated on the day side, consisting of two oppositely oriented circuits.
Schematic diagram of the electric-current pattern in the ionosphere driven by diurnal heating from the Sun. Note that the current is concentrated on the day side, consisting of two oppositely oriented circuits. Source: http://geomag.usgs.gov/in