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Characteristics of the equatorial electrojet current in the central region of South America

Earth, Planets and Space volume 60, pages 623–632 (2008)Cite this article

Abstract

We describe here for the first time the morphology of the equatorial electrojet (EEJ) in the Central American Sector based on an analysis of the geomagnetic field components from six stations distributed on both sides of the dip equator along the 60°W geographic longitude sector. Diurnal and latitudinal variations in the horizontal and vertical components are shown to follow the Chapman model of EEJ. The horizontal component vector due to the ionospheric current aligned itself close to magnetic north, with a mean Declination of 10°W (ranging from 9°W to 14°W). There was a significant counter-electrojet effect before sunrise at stations close to the dip equator, suggesting late reversal of solar-quiet (Sq) electric field in the morning hours. The observed variations in the magnetic meridional current did not seem to be associated with EEJ currents. The centre of the electrojet was around 0.25°S of the dip equator in the morning hours and shifted gradually to 1.5°S by the evening hours. Magnetic storms occurring during the midday hours produced an exceptionally large decrease in the H (horizontal component) field at stations close to the dip equator.

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Authors and Affiliations

  1. Physical Research Laboratory, Ahmedabad, 380009, India

    R. G. Rastogi & H. Chandra

  2. Department of Physics, Gujarat University, Ahmedabad, 380 009, India

    M. E. James

  3. Tokuyama College of Technology, Shunan, Yamaguchi, 745-8585, Japan

    K. Kitamura

  4. Space Environment Research Center, Kyushu University, Fukuoka, Japan

    K. Yumoto

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  1. R. G. Rastogi
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  2. H. Chandra
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  3. M. E. James
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  4. K. Kitamura
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  5. K. Yumoto
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Correspondence to H. Chandra.

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Rastogi, R.G., Chandra, H., James, M.E. et al. Characteristics of the equatorial electrojet current in the central region of South America. Earth Planet Sp 60, 623–632 (2008). https://doi.org/10.1186/BF03353126

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  • DOI: https://doi.org/10.1186/BF03353126

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