Paper#: 79
Poster #:
Session Name: Plenary
Room: West Ballroom
Day: Monday
Time: 8:55-9:20 a.m.
Abstract Title: What Does Auroral Electrojet Dynamics Tell Us About Substorms?
PresentSurname: Kamide, Y.R.
All Authors: Y.R. Kamide
Abstract : The auroral electrojets have long been used to identify onsets of magnetospheric substorms, as well as to monitor the intensity of substorms. A number of empirical models for the large-scale distribution of the electric potential in the ionosphere have been proposed, and these models, which are sorted according to various solar wind conditions, are the result of satellite and radar observations of electric fields. To evaluate these models in terms of how well they can reproduce the reality of the auroral electrojets, it is important to realize that ionospheric convection and electrojet patterns consist of two components. One of them can be predicted reasonably well by proper solar wind parameters, while the other cannot because it is caused by some internal processes in the magnetosphere-ionosphere system. This presentation will summarize recent observations of high-latitude electrodynamic processes, showing that for a given condition in the solar wind, the role of the auroral electrojets and the response of the convection patterns in the ionosphere can vary to a significant degree, depending on the substorm phases. More intense substorms associated with larger southward IMF have been shown to occur at lower latitudes. It is discussed, however, that energy of the auroral electrojets is only a small fraction of the total energy of substorms.