Структура и динамика полярных токовых систем : материалы международного симпозиума «Полярные геомагнитные явления», 25-31 мая, Суздаль, СССР / Акад. наук СССР, Кол. фил. им. С. М. Кирова, Поляр. геофиз. ин-т. – Апатиты : [б. и.], 1988.

„ U K IV t N PROC£SS'' ,,UN10API»)6 PROOE»" Pig. 14. An idealized illustr- ation of the directly driven (lefii and unloading (right) models of the relationship between magneto- aperic energy input W. and energy output W t (Baker et al.,1985T. The second point of view is that the magnetosphere ia a primarily nonlin** ear system (Pig. 14b) in which both the driven and loading-unloading proceases are acting together (Pellinen et al.,1982; Mishin et al.,1982j Rostoker et al., 1983s Y a hnin et al.,1983s Mishin et al.,1984s Baker et al.,1985j Taurutani et al.,1985| Kroehl and Kamide, 1985s Kamide and Baumjohann, 1985). The niain results of these studies are the following! - the onset of enhanced convection is purely IMP controlled. The crosatail currents, the electric field in the plasma sheet and intensity of the convec tion disturbances increase in this period. The ionospheric eastward and weat ward electrojets in the driven system amount to maximum in the dusk and dawn sectors, respectively (see Pig.6); - on the average the solar wind magnetosphere energy coupling function £ gives much higher values than may consume different dissipation mechanisms during the convection disturbances. Hence it is concluded that energy ia stored in the raagnetotail during the conveotion bay which in this case can also be called a substorm growth phases - the growth phase ends in an explosive phase which, however, is not correlated with the IMP development in many cases. Therefore internal magneto- spheric processes due to enhanced energy storage start the explosive phase. Intensity of convection itself does not define conclusively the state of the magnetotail (steady or nonsteady). There is no simple relationship between gross-acale variation of convection intensity and substorm processes in the magnetotailf - the IMP discontinuities during a storage state assist in the substorm onset initiation. The forced substorms may be triggered when the magnetotail conditions are far from the threshold of a large-scale instability. This may lead to a current instability in a localized region of the plasma sheet but not to a large scale process in which most of the stored energy is realized; - following the reduction of energy flow from the solar wind onto the magnetosphere the driven system is decaying while the substorm current wedge may grow. A convincing fact which shows that some substorm expansive phase activity can be driven by the unloading of magnetotail energy stored during the growth of the driven systems - the burst preoipiation of auroral particles and the proper growth of conductivity in the auroral zone may affect in setting a positive feedback in the solar wind-magnetosphere - polar ionosphere system.As a result the energy input into the magnetosphere will enhance not being correlated with solar wind parameters (Mishin et al.,1984). This capability is illustrated in Pig.15 I29