Identification of Night-Time F- Region Currents from CHAMP Satellite Observations over Equatorial Africa

Adero Awuor Ochieng; Paul Baki; Peter Kotze; Collins Mito

doi:10.14331/ijfps.2013.330045

Authors

Adero Awuor Ochieng Department of Technical and Applied Physics, Technical University of Kenya, P.O Box 52428-00200, Nairobi, Kenya Author
Paul Baki Department of Technical and Applied Physics, Technical University of Kenya, P.O Box 52428-00200, Nairobi, Kenya Author
Peter Kotze South Africa National Space Agency (SANSA), P.O Box 32, Hermanus 7200, South Africa Author
Collins Mito Department of Physics, University of Nairobi, P. O. Box 30197, Nairobi, Kenya Author

DOI:

https://doi.org/10.14331/ijfps.2013.330045

Keywords:

Ionosphere, Equatorial ionosphere, ionospheric current systems, magnetic field

Abstract

The F-region currents are generally weak and difficult to detect. However, their contributions to the earth’s magnetic field variations are significant and cannot be ignored by the field modelers. CHAMP satellite has therefore provided a perfect opportunity to investigate the in-situ F-region currents on the night side of the equatorial region. The magnitudes of the current along all the three components of the earth’s magnetic field (X, Y, Z) are investigated. However, in this paper, we present only the results on the Y-component where interesting magnetic residuals were observed. The X and Z-components were rather masked in much noise and would require further filtering. The currents appear in both the pre-midnight and post-midnight sectors and are spatially confined to the equatorial region bounded by the Appleton anomaly. The magnetic residuals are generally observed in the northern hemisphere of an order of 0.8nT, which gives a height-integrated current density of about 1.3mA/m.

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