Transient and steady-state convection in the inner magnetosphere

(poster presented at the Fall 1996 AGU meeting)

D.E. Rowland, M.T. Johnson, J.R. Wygant (School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455)

F.S. Mozer, M. Temerin (Space Sciences Laboratory, University of California, Berkeley, CA 94720)

H. Singer (NOAA R/E/SE Space Environment Center, Boulder, CO 80303)

The large scale three-dimensional ExB flow in the inner magnetosphere is analyzed using observations of electric and magnetic fields made by the CRRES spacecraft between L=2 and L=8 in the ecliptic plane. Data is presented from quiet times as well as intervals during geomagnetic storms. Several periods in which large (> 20 mV/m) electric fields produced bulk flows of 10-200 km/s are identified, and the distribution of these events as well as the direction and magnitude of the quiet-time flows are analyzed and presented as synoptic flow maps.

The analysis shows quiet-time flows towards the equatorial plane near midnight for negative magnetic latitudes, and azimuthal flow around the earth at all local times. The storm-time flows are much larger (by as much as an order of magnitude) but show the same patterns, with azimuthal flow around the earth and strong flows directed towards the equatorial plane.