Variation of atmospheric electric field measured at Vostok, Antarctica, during St. Patrick's Day storms on 24th solar cycle

摘要: The influence of solar wind-magnetosphere interaction on the atmospheric electric field is investigated in connection with two severe geomagnetic storms during 24th cycle. observation was carried out at Vostok (78°27′S, 106°52′E), Antarctica 17-18 March 2013 and 2015. Two consecutive substorms were observed main phase storms, where disturbed ionospheric current anti-sunward morning sector (~04:00-10:00 UT) sunward noon-afternoon (~11:00-16:00 UT). Interplanetary magnetic (IMF) wind enhance potential, which turn couple Potential Gradient (PG) measured ground level. Eventually, for first time, slope ~1.0 Vm-1 per kV has been demonstrated between PG overhead potential (Weimer_05) intense (Kp=8) perturbation. linear relation highly significant positive coupling, i.e., ∆PG changes, whereas offset ~ 25V/m estimated negative coupling. Ionospheric convection map from SuperDARN more compatible coupling changes PG, radar consistent than Weimer_05 model. empirical model compromised when a polar cap dominated by single region associated IMF By <<0. It inferred that superposed effective maintained steady flow, it less significance rapid SW-IMF parameters.