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Variations in the total electron content near the crest of the equatorial ionization anomaly during the November 2004 geomagnetic storm


Space weather studies using a Global Positioning System (GPS) receiver are underway near the crest of the equatorial ionization anomaly (EIA), at Udaipur (MLAT 16.0°N), India. These studies are probably, the first of its kind in the Indian zone near the crest of the EIA. Results for the geomagnetic storm that occurred during November 2004 are presented. Drastic variations in the total electron content (TEC) have been observed as a result of this storm. It is inferred that the reduced levels of TEC following the storm may be attributed to the weakened equatorial plasma fountain due to the disturbance dynamo fields.


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Correspondence to R. Pandey.

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Dashora, N., Pandey, R. Variations in the total electron content near the crest of the equatorial ionization anomaly during the November 2004 geomagnetic storm. Earth Planet Sp 59, 127–131 (2007).

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Key words

  • Space weather
  • Global Positioning System (GPS)
  • geomagnetic storms
  • total electron content (TEC)
  • equatorial ionization anomaly (EIA)