Articles | Volume 36, issue 3
https://doi.org/10.5194/angeo-36-841-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/angeo-36-841-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
13 Jun 2018
Regular paper |
| 13 Jun 2018
| 13 Jun 2018
Statistical analysis of the correlation between the equatorial electrojet and the occurrence of the equatorial ionisation anomaly over the East African sector
Patrick Mungufeni
CORRESPONDING AUTHOR
Mbarara University of Science and Technology, P.O. Box 1410 Mbarara, Uganda
John Bosco Habarulema
South African National Space Agency (SANSA) Space Science, Hermanus 7200, South Africa
Department of Physics and Electronics, Rhodes University, Grahamstown 6140, South Africa
Yenca Migoya-Orué
T/ICT4D laboratory of the Abdus Salam International Center for Theoretical Physics, 34151 Trieste, Italy
Edward Jurua
Mbarara University of Science and Technology, P.O. Box 1410 Mbarara, Uganda
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An unusual geomagnetic storm effect on the ionosphere in the form of localized enhancement of total electron content southward of South Africa is investigated using data from different ionosphere sounding facilities. Global ionospheric maps allow us to get the occurrence rate of such irregularities over the period of 2002–2016 and to see its correlation with solar cycle. The events we detected occur during geomagnetic storms, but not every geomagnetic storm produces such an effect.
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Daytime twin-peak structures, also known as bite-out or diurnal double-maxima structures, are ionospheric phenomena in which the diurnal ionospheric trend shows two peaks (instead of the normal one) during the daytime. This study reports on first simultaneous observations of these structures in the Global Positioning System and ionosonde measurements from the southern African and European middle-latitude stations during a mostly quiet geomagnetic condition period of 8–13 April 2012.
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We have established that, over the East African region, the trough of the equatorial ionisation anomaly (EIA) during high solar activity and quiet geomagnetic conditions lies slightly south of the magnetic equator. During the equinox and December solstice seasons, and a local time interval of 13:00–15:00, the probability of observing the EIA on days with daytime equatorial electrojet (EEJ) strength ≥ 40 nT was mostly > 80 %.
We have established that, over the East African region, the trough of the equatorial ionisation...
