Distinctive plasma density features of the topside ionosphere and their electrodynamics investigated during southern winter

摘要: This study utilizes a novel technique to map the Defense Meteorological Satellite Program (DMSP) data across two hemispheres learn about morphology and plasma composition of topside ionosphere, underlying ionospheric dynamics. In southern winter hemisphere, regional maps tracked heavy-ion (Ni-O+) trough,aurora zone, polar hole, large density depletion. The latter appeared in region South Atlantic Magnetic Anomaly (SAMA). electron temperature (Te) detected thermal characteristics these features, while drifts flux their Results show that there were special electrodynamic effects SAMA due low magnetic field high conductivity. These increased vertical downward (VZ) westward (VY) drifts. Independently, VZ VY registered affected area was depleted heavy ions rich light ions. Some field-aligned profiles impact on trough, which stagnation trough markedly differently at different longitudes. At latitudes ((56 ± 4)S (geomagnetic) when Dstav = 0 nT), elevated temperatures forming Te peak indicated subauroral heating effects. A statistical modeled activity dependence peak’s magnitude location revealed linear correlation with level. Statistically, [10.226 1.355]K moved equatorward [0.051 0.009] per 1 nT decrease averaged Dst index. Per increase AE index, its [1.315 0.444]K movement [0.014 0.003].