Effects of mid-latitude geomagnetic storms on ionospheric Total Electron Content over South Africa

摘要

The development of regional ionospheric Total Electron Content (TEC) models has contributed to understanding the behaviour of the ionosphere and the coupling of the ionosphere to space weather activities on both local and global scales. In the past several decades, the International Global Navigation Satellite Systems (IGS) Service networks of dual frequency receiver data have been applied to construct global and regional models of ionospheric TEC. These models were mainly developed in the Northern Hemisphere where there is a dense network of ground based GNSS receivers for regional data coverage. Such efforts have been historically rare over the African region, and have only recently been initiated. This study reports on the investigation of the effect of mid-latitude geomagnetic storms on TEC over South Africa for selected epochs of Solar Cycles 23 and 24. The MAGIC package was used to estimate TEC over South Africa during Post Solar Maximum, Solar Minimum, and Post Solar Minimum epochs. It is found that TEC is largely determined by the diurnal cycle of solar forcing and subsequent relaxation, but effects due to storms can be determined.