Interhemispheric differences in ionospheric convection: Cluster EDI observations revisited

摘要: The interaction between the interplanetary magnetic field and geomagnetic sets up a large-scale circulation in magnetosphere. This is also reflected magnetically connected ionosphere. In this paper, we present study of ionospheric convection based on Cluster Electron Drift Instrument (EDI) satellite measurements covering both hemispheres obtained over full solar cycle. results from show that average flow patterns polar cap potentials for given orientation can be very different two hemispheres. particular during southward directed conditions, thus enhanced energy input wind, southern has higher cross potential. There are persistent north-south asymmetries, which cannot easily explained by influence external drivers. These asymmetries primarily result significant differences strength configuration Northern Southern Hemispheres. Since ionosphere to magnetosphere, difference will magnetosphere form feedback Consequently, local conditions important large regions geospace.