Space Science Reviews

, Volume 46, Issue 1–2, pp 93–111

The roles of direct input of energy from the solar wind and unloading of stored magnetotail energy in driving magnetospheric substorms

  • G. Rostoker
  • S. I. Akasofu
  • W. Baumjohann
  • Y. Kamide
  • R. L. McPherron


This paper presents the consensus arrived at by the authors with respect to the contributions to the substorm expansive phase of direct energy input from the solar wind and from energy stored in the magnetotail which is released in a sometimes unpredictable manner. Two physical processes, neither of which can be ignored, are considered to be of importance in the dispensation of the energy input from the solar wind. One of these is the ‘driven process’ in which energy, supplied from the solar wind, is directly dissipated in the ionosphere with the only clearly definable delay being due to the inductance of the magnetosphere-ionosphere system. The other is the ‘loading-unloading process’ in which energy from the solar wind is first stored in the magnetotail and then is suddenly released to be deposited in the ionosphere as a consequence of external changes in the interplanetary medium or internal triggering processes. Although the driven process appears to be more dominant on a statistical basis in terms of solar wind-geomagnetic activity relationships, one or the other of the two above processes may dominate for any individual cases. Moreover, the two processes may operate simultaneously during a given phase of the substorm, e.g., the magnetotail may experience loading as the driven system increases in strength. Thus, in our approach, substorms are described in terms of physical processes which we infer to be operative in the magnetosphere and the terminology of the past (e.g., phases) is related to those inferred physical processes. The pattern of substorm development in response to changes in the interplanetary medium is presented for a canonical isolated substorm.


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  1. Akasofu, S.-I.: 1964, Planetary Space Sci. 12, 273.Google Scholar
  2. Akasofu, S.-I. (ed.): 1979, Dynamics of the Magnetosphere, D. Reidel Publ. Co., Dordrecht, Holland, p. 447.Google Scholar
  3. Akasofu, S.-I.: 1981, Space Sci. Rev. 28, 121.Google Scholar
  4. Akasofu, S.-I. and Kan, J. R.: 1982, Planetary Space Sci. 30, 1315.Google Scholar
  5. Axford, W. I. and Hines, C. O.: 1961, Can. J. Phys. 39, 1433.Google Scholar
  6. Baker, D. N., Fritz, T. A., McPherron, R. L., Fairfield, D. H., Kamide, Y., and Baumjohann, W.: 1985, J. Geophys. Res. 90, 1205.Google Scholar
  7. Baumjohann, W.: 1983, Adv. Space Res. 2, 55.Google Scholar
  8. Baumjohann, W., Pellinen, R. J., Opgenoorth, H. J., and Nielsen, E.: 1981, Planetary Space Sci. 29, 431.Google Scholar
  9. Caan, M. N., McPherron, R. L., and Russell, C. T.: 1977, J. Geophys. Res. 82, 4837.Google Scholar
  10. Clauer, C. R., McPherron, R. L., and Searls, C.: 1981, Geophys. Res. Letters 8, 915.Google Scholar
  11. Clauer, C. R., McPherron, R. L., and Searls, C.: 1983, J. Geophys. Res. 88, 2123.Google Scholar
  12. Crooker, N. U. and Siscoe, G. L.: 1981, J. Geophys. Res. 86, 11201.Google Scholar
  13. Fridman, M. and Lemaire, J.: 1980, J. Geophys. Res. 85, 664.Google Scholar
  14. Fukushima, N. and Kamide, Y.: 1973, Rev. Geophys. Space Phys. 11, 795.Google Scholar
  15. Hughes, T. J. and Rostoker, G.: 1979, Geophys. J. 58, 525.Google Scholar
  16. Kamide, Y. and Baumjohann, W.: 1985, J. Geophys. Res. 90, 1305.Google Scholar
  17. Kamide, Y., Perreault, P. D., Akasofu, S.-I., and Winningham, J. D.: 1977, J. Geophys. Res. 82, 5521.Google Scholar
  18. Kisabeth, J. L. and Rostoker, G.: 1974, J. Geophys. Res. 79, 972.Google Scholar
  19. Knight, S.: 1973, Planetary Space Sci. 21, 741.Google Scholar
  20. McPherron, R. L.: 1970, J. Geophys. Res. 75, 5592.Google Scholar
  21. McPherron, R. L.: 1972, Planetary Space Sci. 20, 1521.Google Scholar
  22. Nagata, T. and Kokubun, S.: 1962, J. Ionos. Space Res. Japan 16, 256.Google Scholar
  23. Nishida, A.: 1968, J. Geophys. Res. 73, 1795.Google Scholar
  24. Nishida, A. and Kamide, Y.: 1983, J. Geophys. Res. 88, 7005.Google Scholar
  25. Obayashi, T. and Nishida, A.: 1968, Space Sci. Rev. 8, 3.Google Scholar
  26. Pellinen, R. J., Baumjohann, W., Heikkila, W. J., Sergeev, V. A., Yahnin, A. G., Markland G., and Melnikov, A. O.: 1982, Planetary Space Sci. 30, 371.Google Scholar
  27. Perreault, P. D. and Akasofu, S.-I.: 1978, Geophys. J. Roy. Astron. Soc. 54, 547.Google Scholar
  28. Pytte, T., McPherron, R. L., Hones, E. W., Jr., and West, H. I.: 1978, J. Geophys. Res. 83, 663.Google Scholar
  29. Rostoker, G.: 1983, J. Geophys. Res. 88, 6981.Google Scholar
  30. Rostoker, G. and Boström, R.: 1976, J. Geophys. Res. 81, 235.Google Scholar
  31. Rostoker, G., Akasofu, S.-I., Foster, I., Greenwald, R. A., Kamide, Y. Kawasaki, K., Lui, A. T. Y., McPherron, R. L., and Russell, C. T.: 1980, J. Geophys. Res. 85, 1663.Google Scholar
  32. Rostoker, G., Mareschal, M., and Samson, J. C.: 1982, J. Geophys. Res. 87, 3489.Google Scholar
  33. Sugiura, M.: 1972, J. Geophys. Res. 77, 6093.Google Scholar

Copyright information

© Kluwer Academic Publishers 1987

Authors and Affiliations

  • G. Rostoker
    • 1
  • S. I. Akasofu
    • 2
  • W. Baumjohann
    • 3
  • Y. Kamide
    • 4
    • 5
  • R. L. McPherron
    • 6
  1. 1.Department of Physics and Institute of Earth and Planetary PhysicsUniversity of AlbertaEdmontonCanada
  2. 2.Geophysical Institute, University of AlaskaFairbanksU.S.A.
  3. 3.Institut für Geophysik der Universität, MünsterMünsterF.R.G.
  4. 4.Kyoto Sangyo UniversityKyotoJapan
  5. 5.Space Environment Laboratory, NOAABoulderU.S.A.
  6. 6.Institute of Geophysics and Planetary Physics, University of California (Los Angeles)Los AngelesU.S.A.

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