Apposite of atmospheric electric parameters with the energy coupling function (ε) during geomagnetic storms at high latitude

Abstract

In this paper we are concerned with the variation of the atmospheric electric field and the airearth current due to the excessive power generated by the solar wind-magnetosphere dynamo during geomagnetic storms, recorded at Maitri in Antarctica during 2004. A major part of the powergeneratedbythesolar wind-magnetospheredynamo isusedintheformationofthering current and the rest is utilized for Joule heating and auroral particle precipitation. The method adopted by Frank-Kamenetsky et al. [Frank-Kamenetsky A.V., Troshichev O.A., Burns G.B., Papitashvili V.O., 2001. Variations of atmospheric electric field in the near-pole region related to the interplanetary magnetic field. J. Geophys. Res. 106, A1, 179–190.] was utilized to delineate the variations due to the signatures of tropical thunderstorm activity from the geoelectric data; while statistical methods used in our earlier studies were used to delimit variation due to the constant buffeting of the solar wind. We find that the solar wind-magnetosphere energy coupling function (ε) to be well correlated with the atmospheric electric parameters during the onset of geomagnetic disturbances. However the correlation breaks down during minor storms and sub-storm events.