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Equatorial electrojet in the East Brazil anomaly region

  • The Erratum to this article has been published in Earth, Planets and Space 2014 59:BF03353112


An examination of the geomagnetic field variations at equatorial stations in South America has shown that the daily range of the northward field, H, is about 30% larger in Peru than in Brazil. The midday H field vector in Brazil shows a large westward tilt, corresponding to large westward declination at the station. A significant meridional trans-equatorial current system is suggested for the observed anomaly. The longitudinal variation in the equatorial electrojet current strength is suggested to be due to the corresponding variation in the ionospheric electric field rather than to the electrical conductivity.


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Correspondence to R. G. Rastogi.

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An erratum to this article is available at

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Rastogi, R.G., Yumoto, K. Equatorial electrojet in the East Brazil anomaly region. Earth Planet Sp 59, 103–106 (2007).

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Key words

  • Equatorial electrojet currents
  • longitudinal variation
  • meridional equatorial ionospheric current