Ionospheric convection and the substorm cycle

Lockwood, M. ORCID: https://orcid.org/0000-0002-7397-2172 and Cowley, S.W.H. (1992) Ionospheric convection and the substorm cycle. In: the First International Conference on Substorms, ICS-1, 23-27 March 1992, Kiruna, Sweden, pp. 99-109. (in "Substorms 1, Proceedings of the First International Conference on Substorms, ICS-1", ed C. Mattock, ESA-SP-335 European Space Agency Publications, Nordvijk, The Netherlands)

Abstract/Summary

During substorms, magnetic energy is stored and released by the geomagnetic tail in cycles of growth and expansion phases, respectively. Hence substorms are inherently non-steady phenomena. On the other hand, all numerical models (and most conceptual ones) of ionospheric convection produced to date have considered only steady-state situations. In this paper, we investigate the relationship of substorms to convection. In particular, it is shown that the steady-state convection pattern represents an average over several substorm cycles and does not apply on time scales shorter than the substorm cycle period of 1-2 hours. The flows driven by the growth and expansion phases of substorms are integral (indeed dominant) part of, as opposed to a transient addition to, the overall convection pattern.