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Acta Geophysica

, Volume 62, Issue 3, pp 656–678 | Cite as

Quantifying the EEJ current with ground-based ionosonde inferred vertical E × B drifts in the morning hours over Ilorin, West Africa

  • Jacob O. Adeniyi
  • Isaac A. Adimula
  • Babatunde O. Adebesin
  • Bodo W. Reinisch
  • Olusola A. Oladipo
  • Olayinka Olawepo
  • Kiyohumi Yumoto
Research Article

Abstract

The relationship between the ground-based inferred vertical E × B drifts, Vz, and the magnetic equatorial electrojet current during the year of solar minima was presented. Both the diurnal and seasonal Vz variations are positively directed during the daytime and negative at nighttime. The evening time pre-reversal enhancement occurs around 19:00 LT. The fairly strong linear relationship between the electrojet current strength and Vz exhibited higher correlations during the daytime (06:00–16:00 LT). The maximum morning time proxy parameter described by E = [dH ILR)/dt]max in the morning hours, indicating the east-west electric field in the EEJ, corresponds reasonably well with the E × B drift and, hence, can be used as a proxy parameter for representing Vz in the morning hours. The daytime EEJ magnitude seasonal changes are connected with a change in conductivity emerging from the action of turbulence and divergence of momentum flux. These waves above the dynamo region are suggested to lead to partial counter electrojet during the equinoctial months.

Keywords

equatorial electrojet E × B drifts counter electrojet electric field pre-reversal enhancement 

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Copyright information

© Versita Warsaw and Springer-Verlag Wien 2014

Authors and Affiliations

  • Jacob O. Adeniyi
    • 1
  • Isaac A. Adimula
    • 1
  • Babatunde O. Adebesin
    • 2
  • Bodo W. Reinisch
    • 3
  • Olusola A. Oladipo
    • 1
  • Olayinka Olawepo
    • 1
  • Kiyohumi Yumoto
    • 4
  1. 1.Department of PhysicsUniversity of IlorinIlorinNigeria
  2. 2.Department of Industrial PhysicsLandmark UniversityOmu-Aran, Kwara StateNigeria
  3. 3.Lowell Digisonde International, LLCLowellUSA
  4. 4.Space Environment Research CenterKyushu UniversityFukuokaJapan

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