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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

Earth, Planets and Space volume 60, pages 785–790 (2008)Cite this article

Abstract

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.

References

  • Chapman, S., The equatorial electrojet as detected from the abnormal electric current distributions above Huancayo, Peru, and elsewhere, Arch. Meteorol. Geophys. Bioclimatol., A4, 368–390, 1951.

    Article  Google Scholar 

  • Doumouya, V., Y. Cohen, B. R. Arora, and K. Yumoto, Local time and longitude dependence of the equatorial electrojet magnetic effects, J. Atmos. Solar-Terr. Phys., 65, 1265–1282, 2003.

    Article  Google Scholar 

  • Fambitakoye, O. and P. N. Mayaud, Equatorial electrojet and regular daily variation SR—I. A determination of the equatorial electrojet parameters, J. Atmos. Terr. Phys., 38, 1–17, 1976.

    Article  Google Scholar 

  • Forbes, J. M., The Equatorial Electrojet, Rev. Geophys. Space Phys., 19, 469–504, 1981.

    Article  Google Scholar 

  • Forbes, J. M. and S. Leveroni, Quasi 16-day oscillation in the ionosphere, Geophys. Res. Lett., 19, 981–984, 1992.

    Article  Google Scholar 

  • Forbes, J. M., M. E. Hagan, S. Miyahara, F. Vial, A. H. Manson, C. E. Meek, and Y. I. Portnyagin, Quasi 16-day oscillation in the mesosphere and lower thermosphere, J. Geophys. Res., 100, 9149–9163, 1995.

    Article  Google Scholar 

  • Gouin, P., Reversal of the magnetic daily variation at Addis Ababa, Nature, 193, 1145–1146, 1962.

    Article  Google Scholar 

  • Kikuchi, T., H. Lühr, T. Kitamura, O. Saka, and K. Schlegel, Direct penetration of the polar electric field to the equator during a DP 2 event as detected by the auroral and equatorial magnetometer chains and the EISCAT radar, J. Geophys. Res., 101, 17,161–17,173, 1996.

    Article  Google Scholar 

  • Kikuchi, T., K. Hashimoto, T.-I. Kitamura, H. Tachihara, and B. Fejer, Equatorial counterelectrojets during substorms, J. Geophys. Res., 108(A11), 1406, doi:10.1029/2003JA009915, 2003.

    Article  Google Scholar 

  • Kobea, A. T., C. Amory-Mazudier, J. M. Do, H. Lühr, E. Houngninou, J. Vassal, E. Blanc, and J. J. Curto, Equatorial electrojet as part of the global circuit: a case-study from the IEEY, Ann. Geophys., 16, 698–710, 1998.

    Article  Google Scholar 

  • Mayaud, P. N., The equatorial counter-electrojet—a review of its geomagnetic aspects, J. Atmos. Terr. Phys., 39, 1055–1070, 1977.

    Article  Google Scholar 

  • Nishida, A., Geomagnetic DP 2 fluctuations and associated magnetospheric phenomena, J. Geophys. Res., 73, 1795–1803, 1968.

    Article  Google Scholar 

  • Onwumechilli, C. A., The Equatorial Electrojet, Gordon and Breach Science Publishers, Netherlands, 1997.

    Google Scholar 

  • Osborne, D. G., Position and movement of the equatorial electrojet over Ghana, J. Atmos. Terr. Phys., 24, 491–502, 1962.

    Article  Google Scholar 

  • Perreault, P. and S.-I. Akasofu, A study of geomagnetic storms, Geophys. J. R. Astron. Soc., 54, 547, 1978.

    Article  Google Scholar 

  • Rastogi, R. G., Lunar effects in the counter electrojet near the magnetic equator, J. Atmos. Terr. Phys., 36, 167–170, 1974.

    Article  Google Scholar 

  • Rastogi, R. G., Critical problems of equatorial electrojet, Adv. Space. Res., 12, 13–21, 1992.

    Article  Google Scholar 

  • Rigoti, A., F. H. Chamalaun, N. B. Trivedi, and A. L. Padilha, Characteristics of the Equatorial Electrojet determined from an array ofmagnetometers in N-NE Brazil, Earth Planets Space, 51, 115–128, 1999.

    Article  Google Scholar 

  • Shinohara, M., K. Yumoto, A. Yoshikawa, O. Saka, S. I. Solovyev, E. F. Vershinin, N. B. Trivedi, J. M. Da Costa, and The 210° MM Magnetic Observation Group, Wave characteristics of daytime and nighttime Pi 2 pulsations at the equatorial and low latitudes, Geophys. Res. Lett., 24, 2279–2282, 1997.

    Article  Google Scholar 

  • Sugiura, M., Hourly values of equatorial Dst for the IGY, Goddard Space Flight Center, Greenbelt, Maryland, NASA Rept., X-611-63-131, June, 1963.

    Google Scholar 

  • Yumoto, K. and the MAGDAS Group, MAGDAS project and its application for space weather, in Solar Influence on the Heliosphere and Earth’s Environment: Recent Progress and Prospects, edited by N. Gopalswamy and A. Bhattacharya, ISBN-81-87099-40-2, 399–405, 2006.

    Google Scholar 

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Authors and Affiliations

  1. Space Environment Research Center, Kyushu University, 6-10-1 Hakozaki, Fukuoka, Japan

    T. Uozumi, K. Yumoto, S. Abe, Y. Kakinami, M. Shinohara, A. Yoshikawa & H. Kawano

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

    K. Kitamura

  3. Department of Earth and Planetary Sciences, Kyushu University, 6-10-1 Hakozaki, Fukuoka, Japan

    T. Ueno & T. Tokunaga

  4. Manila Observatory, Bldg. at Ateneo de Manila University Campus, Quezon City, Philippines

    D. McNamara

  5. Observatorio de Ancón, Instituto Geofísico del Perú, Carretera Panamericana Norte Km. 43.5, Ancón, Peru

    J. K. Ishituka

  6. National Institute for Space Research (INPE), 12227-010, Sao Jose dos Campos, SP, Brazil

    S. L. G. Dutra

  7. Department of Physics, Bahir Dar University, Bahir Dar, PB 79, Ethiopia

    B. Damtie

  8. Laboratorire de Physique de l’Atmosphere, University of Cocody, BPV34, Abidijan, Cote d’Ivoire

    V. Doumbia & O. Obrou

  9. Department of Physics, Federal University of Technology, PMB 704, Akure, Ondo State, Nigeria

    A. B. Rabiu

  10. Department of Physics, University of Ilorin, Ilorin, Kwara State, Nigeria

    I. A. Adimula

  11. National Space Agency, Ministry of Science, Technology and Innovation, 62100, Putrajaya, Malaysia

    M. Othman & M. Fairos

  12. Department of Physics, University of San Carlos, Cebu City, Philippines

    R. E. S. Otadoy

Authors
  1. T. Uozumi
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  2. K. Yumoto
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  3. K. Kitamura
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  4. S. Abe
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  5. Y. Kakinami
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  6. M. Shinohara
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  7. A. Yoshikawa
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  8. H. Kawano
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  9. T. Ueno
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  10. T. Tokunaga
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  11. D. McNamara
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  12. J. K. Ishituka
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  13. S. L. G. Dutra
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  14. B. Damtie
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  15. V. Doumbia
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  16. O. Obrou
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  17. A. B. Rabiu
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  18. I. A. Adimula
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  19. M. Othman
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  20. M. Fairos
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  21. R. E. S. Otadoy
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MAGDAS Group

Corresponding author

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). https://doi.org/10.1186/BF03352828

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  • DOI: https://doi.org/10.1186/BF03352828

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