Features of the Night-Time F-Region Currents Over Equatorial Africa (August, 2001)
Keywords:Ionosphere, Equatorial ionosphere, ionospheric current systems, magnetic field
In this paper, we present the features of the equatorial F-region current systems over equatorial Africa during nighttime on 05thAugust, 2001 observed at midnight. The observations have inferred from in situ CHAMP satellite measurements of the vector magnetic field. The magnitudes of the current along all the three magnetic field components of the Earth’s magnetic field varied considerably. The Bx-component recorded a diamagnetic effect of about 8nT, By-component recorded a current density of 5mA/m, and Bz-component reached a value of 3mA/m. The F-region dynamo, gravity dynamo and plasma-pressure gradients are the possible mechanisms for the occurrence of these currents. The signatures confined to the equatorial region bounded by the Appleton anomaly.
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