Longitudinal effect in the response of total electron content to magnetic storms

Abstract

IN a previous study¹ of the response of the ionospheric total electron content (TEC) data to magnetic storms, an average storm time behaviour of TEC for middle latitudes was deduced. On average TEC is enhanced during the first 24 h following the start of a storm, depressed for the next 24 h and near normal through the third 24 h. Another study² has shown a strong diurnal component in TEC behaviour with the maximum enhancement occurring in the dusk sector (1600 to 1800 LT). The present study of disturbed TEC behaviour generally agrees with that reported above but in addition indicates a longitudinal effect in the behaviour of both the storm time and diurnal components of disturbed TEC.