HR: 08:00h
AN: SM11C-01 INVITED [Abstracts]
TI: Magnetospheric Convection as a Global Force Phenomenon
AU: * Siscoe, G
EM: siscoe@bu.edu
AB:
Since 1959 when Thomas Gold showed that motions in the magnetosphere were possible despite plasma
being frozen to the magnetic field, magnetospheric convection as a subject of study has gone through several
stages (to be reviewed) leading to a recent one that integrates convection into a global system of balance of
forces. This area of research has opened by focusing on the region 1 current system as a carrier of force
between the solar wind and the ionosphere/thermosphere fluid. An important result to emerge from it is the
realization that the force that the solar wind delivers to the magnetosphere in being transferred by the region 1
current system to the ionosphere/thermosphere fluid is amplified by about an order of magnitude. (Vasyliunas
refers to this as "leveraging.") The apparent violation of Newton's Third Law results from the main participants in
the force balance being not the solar wind force but the JxB force on the ionosphere/thermosphere fluid and the
mu-dot-grad-B force on the Earth's dipole. This talk extends the study by considering the global force-balance
problem separately for the Pedersen current (a completion of the region 1 problem), the Hall current (thus
introducing the region 2 current system), and the Cowling current (bringing in the substorm current wedge). The
approach is through representing the ionosphere/thermosphere fluid by the shallow water equations. Novelties
that result include force balance by means of tidal bulges and tidal bores.
DE: 2427 Ionosphere/atmosphere interactions (0335)
DE: 2437 Ionospheric dynamics
DE: 2736 Magnetosphere/ionosphere interactions (2431)
DE: 2760 Plasma convection (2463)
DE: 2784 Solar wind/magnetosphere interactions
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting