The Response of the Equatorial Ionosphere over Nigeria to a Geomagnetic Storm Event

Abstract

Abstract—The total electron content (TEC) data obtained from the ground-based GPS receiver stations of the Nigerian GNSS network of stations (NIGNET) have been used in this study to analyse the response of equatorial and low-latitude ionosphere to strong geomagnetic storms that occurred on October 25, 2011. The stations and their respective geomagnetic latitudes are Lagos (−3.03°), Yola (−1.32°) and Birnin Kebbi (0.72°). The storm caused enhancements in TEC (positive storm effect) in comparison with the quiet condition’s TEC across all the stations during both the main and the recovery phases. During the storm of October 25, recorded maximum enhancements in TEC were 181.86%, 142.34% and 181.24% in Kebbi, Yola and Lagos respectively.The magnitude of the ionospheric irregularities was higher at the night (October 25) of the main phase of the geomagnetic storm than the night (October 24) before the storm onset.