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A new index to monitor temporal and long-term variations of the equatorial electrojet by MAGDAS/CPMN real-time data: EE-Index


A new index, EE-index (EDst, EU, and EL), is proposed to monitor temporal and long-term variations of the equatorial electrojet by using theMAGDAS/CPMN real-time data. The mean value of the H component magnetic variations observed at the nightside (LT = 18–06) MAGDAS/CPMN stations along the magnetic equatorial region is found to show variations similar to those of Dst; we defined this quantity as EDst. The EDst can be used as a proxy of Dst for the real-time and long-term geospace monitoring. By subtracting EDst from the H component data of each equatorial station, it is possible to extract the Equatorial Electrojet and Counter Electrojet components, which are defined as EU and EL, respectively.


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Correspondence to T. Uozumi.

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Uozumi, T., Yumoto, K., Kitamura, K. et al. A new index to monitor temporal and long-term variations of the equatorial electrojet by MAGDAS/CPMN real-time data: EE-Index. Earth Planet Sp 60, 785–790 (2008).

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Key words

  • EE-index
  • equatorial electrojet
  • counter electrojet
  • real-time monitoring
  • Dst index
  • space weather