Paper#: 56
Poster #: 2
Session Name: Poster Session 2
Room: East Ballroom
Day: Thursday
Time: 10:10 a.m.-Noon
Abstract Title: Non-substorm Mechanism for Magnetic Storms
PresentSurname: Maltsev, Y.P
All Authors: Y.P. Maltsev
Abstract : As shown by Maltsev et al. [JGR, 1996, V.101, 7697] and Arykov and Maltsev [GRL, 1996, V.23, 1689] the magnetospheric electric currents produce in the Earth dipole center the magnetic disturbance Bz = f(p) - F/3S where f(p) is a function dependent on the plasma pressure in the magnetosphere and magnetosheath, S is the equatorial cross-section of the stable trapping region in the inner magnetosphere, F is the magnetic flux outside this region. The IMF southward component enhances the magnetic flux transport from the dayside to the magnetotail so that F grows and S drops. According to the formula given above, this results in the growth of the magnetic depression in the inner magnetosphere. The flux variation is dF/dt = C where C is the electric field circulation along the stable trapping boundary. The circulation can be presented as C = U - (F-Fo)/T where U is the electric potential difference between the dawn and dusk sides of the inner magnetosphere, Fo is the undisturbed high-latitude magnetic flux, T is the flux relaxation time. If we use the well-known statistical relation of the convection potential to the solar wind parameters [Boyle et al., JGR, 1997, V.102, 111] we can explain the empirical relationship between the Dst growth rate and southward IMF obtained by Burton et al. [JGR, 1975, 80, 4204]. Substorms are not a necessary point in this model.