Investigation of Scintillation Occurrence during Intense Geomagnetic Storms at low latitude stations

1.      Abstract GPS-derived scintillation index S4 from three low latitude stations located at the Equatorial Ionisation Anomaly (EIA) region has been analysed with a view to knowing the contribution of geomagnetic storms on scintillation occurrence. Results showed that scintillation at low latitude stations was dependent on location, the phase of the storm and time of occurrence of storm. Addis Ababa recorded moderate values of  S4, ranging from 0.42 to 0.45 during the storm events considered. Ile-Ife recorded both low and moderate values of S4, ranging from 0.2 to 0.42, while Bangalore station recorded the least scintillation occurrence, with S4 values ranging from 0.1 to 0.3. Results also revealed that scintillation occurrence during storms can be inhibited or triggered depending on the phase of the storm. Comparative result between scintillation occurrence during storm and that during quiet time showed that scintillation was more pronounced during quiet periods over all stations.

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