Geomagnetic Storm Variation of Vertical Total Electron Content (VTEC) Over Some Euro-African Stations

Obiageli J. Ugonabo

Department of Physics and Astronomy, University of Nigeria, Nsukka, Nigeria.

Ernest Benjamin Ikechukwu Ugwu *

Department of Physics and Astronomy, University of Nigeria, Nsukka, Nigeria and Natural Science Unit, University of Nigeria, Nsukka, Nigeria.

Kingsley C. Okpala

Department of Physics and Astronomy, University of Nigeria, Nsukka, Nigeria.

Godsfavour C. Amanekwe

Department of Physics and Astronomy, University of Nigeria, Nsukka, Nigeria.

*Author to whom correspondence should be addressed.


Geomagnetic storms are events which have physical effects on some ionospheric parameters that, to some extent,affects  the state and dynamics of the ionosphere  with important implications on GNSS applications. Here, the total electron content (TEC) of Brussels (50.80oN, 04.37oE), Madrid (40.43oN, 04.25oW) and Irkutsk (52.22oN, 104.32oE), which are all mid-latitude European stations are compared with Libreville (00.35oN, 09.67oE) and Lusaka (15.43oS, 28.32oE) which are equatorial and low-latitude stations respectively. This study is done over two geomagnetic storms that took place in the solstice period of 2004. Deviations of storm time VTEC from solar quiet (Sq) averages are calculated, analysed and presented. Similarities and differences of storm effects are observed in the European stations with enhancements and depressions. Diurnal solar quiet day variations showed high VTEC during the post-noon hours for all the stations. The VTEC deviations during storm time at Libreville lie within, for Lusaka it is. For the mid-latitude European stations, the deviations are lower such that  is recorded at Brussels while  is recorded for both Irkutsk and Madrid. Enhancement of VTEC during the daytime storm period is attributable to the super-fountain effect caused by the prompt penetration electric fields (PPEFs) into the ionosphere and magnetosphere while low VTEC at night-time is attributed to the process of recombination.   Understanding the behaviour of the ionosphere during geomagnetic storms is important and necessary for a better understanding of the applications of GNSS.

Keywords: Total electron content, geomagnetic storm, prompt penetration electric fields, recombination

How to Cite

Ugonabo , O. J., Ugwu , E. B. I., Okpala , K. C., & Amanekwe , G. C. (2024). Geomagnetic Storm Variation of Vertical Total Electron Content (VTEC) Over Some Euro-African Stations. Physical Science International Journal, 28(1), 23–34.


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Dungey JW. Interplanetary magnetic field and the auroral zones. Physical Review Letters. 1961;6(2):47.

Gonzalez WD, Joselyn J, Kamide Y, Kroehl HW, Rostoker G, Tsurutani BT, Vasyliunas VM. What is a geomagnetic storm?Journal of Geophysical Research: Space Physics. 1994;99(A4):5771-5792.

Okpala KC, Ogbonna CE. On the mid latitude ionospheric storm association with intense geomagnetic storms. Advances in Space Research. 2018;61(7):1858- 1872.

Buonsanto MJ, Fuller-Rowell TJ. Strides made in understanding space weather at Earth. Eos, Transactions American Geophysical Union. 1997;78(1):1-7.

Malik R, Sarkar S, Mukherjee S, Gwal, AK. Study of ionospheric variability during geomagnetic storms. Journal of Indian Geophysics Union. 2010;14(1):47-56.

Bagiya MS, Thampi S, Aggarwal M, Ravindran S, Joshi HP, Iyer KN, Manju G. & Sridharan R. Geomagnetic storm effect on low-latitude total electron content. 37th COSPAR Scientific Assembly. 2008;37: 158.

Chakraborty SK, Hajra R. Variability of total electron content near the crest of the equatorial anomaly during moderate geomagnetic storms. Journal of Atmospheric and Solar-terrestrial Physics. 2010;72(11-12):900-911.

Azzouzi I, Migoya-Orue Y, Mazaudier CA, Fleury R, Radicella SM, Touzani A. (2015). Signatures of solar events at middle and low latitudes in the Europe-African sector, during geomagnetic storms, October Advances in Space Research. 2013;56(9):2040–2055.

Edward U, Boniface N, George O. Variability of VTEC gradient and TEC rate index over Kisumu , Kenya during selected quiet and storm days of 2013 and 2014. American Journal of Astronomy and Astrophysics. 2019;7(4):67–72. Available:

Okpala KC, Ugwu EB, Attah OJ, Obiegbuna D, Anamezie RC, Egbunu F. Variation of vertical total electron content ( TEC ) over West Africa during geomagnetic storms. Physical Science International Journal. 2020;24(5):52–63. Abailable:

Ugonabo OJ, Amanekwe GC, Okpala, KC. Seasonal variability of total electron content in low latitude region of West Africa. Publication of the Astronomical Society of Nigeria. 2020;5:8-14.

Norsuzila Y, Abdullah M, Ismail M. GPS total electron content (TEC) prediction at ionosphere layer over the Equatorial Region, Trends in Telecommunications Technologies, Christos J Bouras (Ed.); 2010. ISBN: 978-953-307-072-8, InTech, Available: prediction-at-ionosphere-layer-over-the-equatorial-region.

Mehmood M, Naqvi NA, Saleem S. GPS Total Electron Content (TEC) estimation using single station measurements. Institute of Electrical and Electronics Engineering. 2019:0–4.

Tsurutani BT, Verkhoglyadova OP, Manucci AJ, Saito A, Araki T, Yumoto K, Tsuda T, Abdu MA, Sobral JHA, Gonzalez WD, McCreadie H, Lakhina GS, Vasyliunas VM. Prompt penetration electric fields (PPEFs) and their ionospheric effects during the great magnetic storm of 30-31, October 2003. Journal of Geophysical Research: Space physics. 2008;113:(A5).

Nambda S, Maeda KI. Radio Wave Propagation, Tokyo: Corona. 1939;86.