Yakutsk, Russian Federation
Geomagnetic activity asymmetry in the Northern and Southern hemispheres is studied. It is shown that the higher is the level of magnetic activity the greater is the asymmetry. It is found that the asymmetry in the hemispheres manifests itself in the 06–18-hour component of magnetic activity diurnal variation, while the asymmetry in the 00–12-hourly component is completely absent. The cause of geomagnetic north-south asymmetry is supposed to be meridional Pedersen current between high and middle latitudes in the ionosphere. A qualitative model of formation of asymmetry connected with the solar wind electric field is proposed.
Geomagnetic activity, Earth’s magnetosphere, interplanetary magnetic field
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