Equatorial Ionization Anomaly: The Role of Thermospheric Winds and the Effects of the Geomagnetic Field Secular Variation

  • Inez S. BatistaEmail author
  • Erica M. Diogo
  • Jonas R. Souza
  • Mangalathayil Ali Abdu
  • Graham J. Bailey
Part of the IAGA Special Sopron Book Series book series (IAGA, volume 2)


The vertical plasma drift is the well known driver of the equatorial ionization anomaly (EIA). The latitudinal distribution of ionization in the EIA is determined also by thermospheric meridional wind whose precise role can only be evaluated through the use of theoretical models because it depends not only upon the local configuration of the wind, but is a complex function of its distribution along the entire magnetic field line. Besides, in the Brazilian region, the magnetic field secular variations are fast enough for their effects on the ionosphere to be observed in the time span of the order of a solar cycle. In this work we use the Sheffield University Plasmasphere-Ionosphere Model (SUPIM) to investigate the role of the vertical plasma drift, thermospheric meridional wind and of the magnetic field secular variations in the changing trend of the EIA over the Brazilian region.


Meridional Wind Magnetic Equator Drift Model International Geomagnetic Reference Field Vertical Drift 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was partially supported by CNPq under grant 301643/2009-1.


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Inez S. Batista
    • 1
    Email author
  • Erica M. Diogo
    • 1
    • 2
  • Jonas R. Souza
    • 1
  • Mangalathayil Ali Abdu
    • 1
  • Graham J. Bailey
    • 3
  1. 1.National Institute for Space ResearchSão José dos CamposBrazil
  2. 2.Universidade Estadual do Rio de Janeiro – Campus Regional de ResendeResendeBrazil
  3. 3.Department of Applied MathematicsSheffield UniversitySheffieldUK

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