Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity

Mustapha Abbas; Mohammed Bello Kaoje; Mukhtar Mohammad; Mukhtar Ibrahim Furfuri; Arzika Yusuf Koko; Aminu Muhammad; Asabe Audu Ibrahim

doi:doi:10.11648/j.earth.20251406.11

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Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity

Mustapha Abbas^*

, Mohammed Bello Kaoje, Mukhtar Mohammad

, Mukhtar Ibrahim Furfuri

, Arzika Yusuf Koko

, Aminu Muhammad

, Asabe Audu Ibrahim

Published in Earth Sciences (Volume 14, Issue 6)

Received: 10 May 2025 Accepted: 26 May 2025 Published: 28 November 2025

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Abstract

It is a widely accepted fact that the quiet-time equatorial electrojet (EEJ) is a prominent narrow band of enhanced daytime eastward current flowing basically in the ionospheric E-region within ± 3° latitude of the dip equator. Studies have shown over the years that at least two magnetic stations are required to estimate the daytime variability strength of the EEJ. One station must be situated within the EEJ strip (station whose EEJ strength is to be determined) and the other displaced just outside the EEJ influence. One of the open issues in estimating the strength of the EEJ has been the actual latitudinal distance of the off-equatorial station from the equatorial region. This has given rise to different schools of thought in estimating the variability strength of the EEJ. This paper outlined for the first time the latitudinal extent required of the off-equatorial station which is longitudinally aligned with the equatorial station and step-by-step procedure required for estimating the daytime equatorial electrojet and the latitudinal extent ideal for choosing the off-equatorial station aligned to the equatorial station. The result from this study will clarify on the latitudinal extent required for estimating the variability strength of the EEJ in the African sector and invariably provide to some extent the role of equatorial electrojet on the distribution of equatorial ionization at low latitude in this region.

Published in	Earth Sciences (Volume 14, Issue 6)
DOI	10.11648/j.earth.20251406.11
Page(s)	215-224
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2025. Published by Science Publishing Group

Keywords

Ionosphere, Atmosphere, Equatorial Electrojet, Geomagnetic Field, Solar Quiet (Sq) Current

References

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APA Style

Abbas, M., Kaoje, M. B., Mohammad, M., Furfuri, M. I., Koko, A. Y., et al. (2025). Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity. Earth Sciences, 14(6), 215-224. https://doi.org/10.11648/j.earth.20251406.11

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ACS Style

Abbas, M.; Kaoje, M. B.; Mohammad, M.; Furfuri, M. I.; Koko, A. Y., et al. Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity. Earth Sci. 2025, 14(6), 215-224. doi: 10.11648/j.earth.20251406.11

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AMA Style

Abbas M, Kaoje MB, Mohammad M, Furfuri MI, Koko AY, et al. Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity. Earth Sci. 2025;14(6):215-224. doi: 10.11648/j.earth.20251406.11

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@article{10.11648/j.earth.20251406.11,
  author = {Mustapha Abbas and Mohammed Bello Kaoje and Mukhtar Mohammad and Mukhtar Ibrahim Furfuri and Arzika Yusuf Koko and Aminu Muhammad and Asabe Audu Ibrahim},
  title = {Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity
},
  journal = {Earth Sciences},
  volume = {14},
  number = {6},
  pages = {215-224},
  doi = {10.11648/j.earth.20251406.11},
  url = {https://doi.org/10.11648/j.earth.20251406.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.earth.20251406.11},
  abstract = {It is a widely accepted fact that the quiet-time equatorial electrojet (EEJ) is a prominent narrow band of enhanced daytime eastward current flowing basically in the ionospheric E-region within ± 3° latitude of the dip equator. Studies have shown over the years that at least two magnetic stations are required to estimate the daytime variability strength of the EEJ. One station must be situated within the EEJ strip (station whose EEJ strength is to be determined) and the other displaced just outside the EEJ influence. One of the open issues in estimating the strength of the EEJ has been the actual latitudinal distance of the off-equatorial station from the equatorial region. This has given rise to different schools of thought in estimating the variability strength of the EEJ. This paper outlined for the first time the latitudinal extent required of the off-equatorial station which is longitudinally aligned with the equatorial station and step-by-step procedure required for estimating the daytime equatorial electrojet and the latitudinal extent ideal for choosing the off-equatorial station aligned to the equatorial station. The result from this study will clarify on the latitudinal extent required for estimating the variability strength of the EEJ in the African sector and invariably provide to some extent the role of equatorial electrojet on the distribution of equatorial ionization at low latitude in this region.},
 year = {2025}
}

Copy | Download

TY  - JOUR
T1  - Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity

AU  - Mustapha Abbas
AU  - Mohammed Bello Kaoje
AU  - Mukhtar Mohammad
AU  - Mukhtar Ibrahim Furfuri
AU  - Arzika Yusuf Koko
AU  - Aminu Muhammad
AU  - Asabe Audu Ibrahim
Y1  - 2025/11/28
PY  - 2025
N1  - https://doi.org/10.11648/j.earth.20251406.11
DO  - 10.11648/j.earth.20251406.11
T2  - Earth Sciences
JF  - Earth Sciences
JO  - Earth Sciences
SP  - 215
EP  - 224
PB  - Science Publishing Group
SN  - 2328-5982
UR  - https://doi.org/10.11648/j.earth.20251406.11
AB  - It is a widely accepted fact that the quiet-time equatorial electrojet (EEJ) is a prominent narrow band of enhanced daytime eastward current flowing basically in the ionospheric E-region within ± 3° latitude of the dip equator. Studies have shown over the years that at least two magnetic stations are required to estimate the daytime variability strength of the EEJ. One station must be situated within the EEJ strip (station whose EEJ strength is to be determined) and the other displaced just outside the EEJ influence. One of the open issues in estimating the strength of the EEJ has been the actual latitudinal distance of the off-equatorial station from the equatorial region. This has given rise to different schools of thought in estimating the variability strength of the EEJ. This paper outlined for the first time the latitudinal extent required of the off-equatorial station which is longitudinally aligned with the equatorial station and step-by-step procedure required for estimating the daytime equatorial electrojet and the latitudinal extent ideal for choosing the off-equatorial station aligned to the equatorial station. The result from this study will clarify on the latitudinal extent required for estimating the variability strength of the EEJ in the African sector and invariably provide to some extent the role of equatorial electrojet on the distribution of equatorial ionization at low latitude in this region.
VL  - 14
IS  - 6
ER  -

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Author Information

Mustapha Abbas

Department of Physics, Kebbi State University of Science and Technology, Aliero, Nigeria

Contact Email

http://orcid.org/0000-0002-3923-5582
Mohammed Bello Kaoje

Department of Physics, Kebbi State University of Science and Technology, Aliero, Nigeria
Mukhtar Mohammad

Department of Physics, Federal University of Agriculture, Zuru, Nigeria

http://orcid.org/0000-0002-3923-5582
Mukhtar Ibrahim Furfuri

Department of Physics, Kebbi State University of Science and Technology, Aliero, Nigeria; Department of Physics, Federal College of Education Technical, Gusau, Nigeria

http://orcid.org/0009-0002-5022-2093
Arzika Yusuf Koko

Department of Physics, Kebbi State University of Science and Technology, Aliero, Nigeria; Department of Physics, Federal University Of Education, Kotangora, Nigeria

http://orcid.org/0009-0001-0352-2686
Aminu Muhammad

Department of Physics, Kebbi State University of Science and Technology, Aliero, Nigeria

http://orcid.org/0000-0002-3923-5582
Asabe Audu Ibrahim

Department of Physics, Federal University of Agriculture, Zuru, Nigeria

http://orcid.org/0000-0002-3923-5582

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APA Style

Abbas, M., Kaoje, M. B., Mohammad, M., Furfuri, M. I., Koko, A. Y., et al. (2025). Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity. Earth Sciences, 14(6), 215-224. https://doi.org/10.11648/j.earth.20251406.11

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ACS Style

Abbas, M.; Kaoje, M. B.; Mohammad, M.; Furfuri, M. I.; Koko, A. Y., et al. Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity. Earth Sci. 2025, 14(6), 215-224. doi: 10.11648/j.earth.20251406.11

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AMA Style

Abbas M, Kaoje MB, Mohammad M, Furfuri MI, Koko AY, et al. Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity. Earth Sci. 2025;14(6):215-224. doi: 10.11648/j.earth.20251406.11

Copy | Download

@article{10.11648/j.earth.20251406.11,
  author = {Mustapha Abbas and Mohammed Bello Kaoje and Mukhtar Mohammad and Mukhtar Ibrahim Furfuri and Arzika Yusuf Koko and Aminu Muhammad and Asabe Audu Ibrahim},
  title = {Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity
},
  journal = {Earth Sciences},
  volume = {14},
  number = {6},
  pages = {215-224},
  doi = {10.11648/j.earth.20251406.11},
  url = {https://doi.org/10.11648/j.earth.20251406.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.earth.20251406.11},
  abstract = {It is a widely accepted fact that the quiet-time equatorial electrojet (EEJ) is a prominent narrow band of enhanced daytime eastward current flowing basically in the ionospheric E-region within ± 3° latitude of the dip equator. Studies have shown over the years that at least two magnetic stations are required to estimate the daytime variability strength of the EEJ. One station must be situated within the EEJ strip (station whose EEJ strength is to be determined) and the other displaced just outside the EEJ influence. One of the open issues in estimating the strength of the EEJ has been the actual latitudinal distance of the off-equatorial station from the equatorial region. This has given rise to different schools of thought in estimating the variability strength of the EEJ. This paper outlined for the first time the latitudinal extent required of the off-equatorial station which is longitudinally aligned with the equatorial station and step-by-step procedure required for estimating the daytime equatorial electrojet and the latitudinal extent ideal for choosing the off-equatorial station aligned to the equatorial station. The result from this study will clarify on the latitudinal extent required for estimating the variability strength of the EEJ in the African sector and invariably provide to some extent the role of equatorial electrojet on the distribution of equatorial ionization at low latitude in this region.},
 year = {2025}
}

Copy | Download

TY  - JOUR
T1  - Features of Quiet-time Magnetic Field and Simple Approach to Estimate the Variability Strength of Equatorial Electrojet (EEJ) Current Intensity

AU  - Mustapha Abbas
AU  - Mohammed Bello Kaoje
AU  - Mukhtar Mohammad
AU  - Mukhtar Ibrahim Furfuri
AU  - Arzika Yusuf Koko
AU  - Aminu Muhammad
AU  - Asabe Audu Ibrahim
Y1  - 2025/11/28
PY  - 2025
N1  - https://doi.org/10.11648/j.earth.20251406.11
DO  - 10.11648/j.earth.20251406.11
T2  - Earth Sciences
JF  - Earth Sciences
JO  - Earth Sciences
SP  - 215
EP  - 224
PB  - Science Publishing Group
SN  - 2328-5982
UR  - https://doi.org/10.11648/j.earth.20251406.11
AB  - It is a widely accepted fact that the quiet-time equatorial electrojet (EEJ) is a prominent narrow band of enhanced daytime eastward current flowing basically in the ionospheric E-region within ± 3° latitude of the dip equator. Studies have shown over the years that at least two magnetic stations are required to estimate the daytime variability strength of the EEJ. One station must be situated within the EEJ strip (station whose EEJ strength is to be determined) and the other displaced just outside the EEJ influence. One of the open issues in estimating the strength of the EEJ has been the actual latitudinal distance of the off-equatorial station from the equatorial region. This has given rise to different schools of thought in estimating the variability strength of the EEJ. This paper outlined for the first time the latitudinal extent required of the off-equatorial station which is longitudinally aligned with the equatorial station and step-by-step procedure required for estimating the daytime equatorial electrojet and the latitudinal extent ideal for choosing the off-equatorial station aligned to the equatorial station. The result from this study will clarify on the latitudinal extent required for estimating the variability strength of the EEJ in the African sector and invariably provide to some extent the role of equatorial electrojet on the distribution of equatorial ionization at low latitude in this region.
VL  - 14
IS  - 6
ER  -

Copy | Download