Observations of magnetospheric convection from low altitudes

The high-latitude ionosphere is considered as a convenient 'viewing screen' for deducing magnetospheric convection, since the footprints of the immense volume of the magnetospheric flux tubes map to a considerably more manageable surface area. This area is, however, still very large, and an instantaneous measurement of the flow pattern over the entire high latitude region is presently not feasible. Therefore, much effort has been made in synthesizing many passes of polar orbiting spacecraft into convection patterns. The present investigation follows the development of a description of the global convection pattern and its dependence on the interplanetary magnetic field (IMF). The convection pattern is described in terms of the plasma flow speed and direction. Attention is given to the southward interplanetary magnetic field and the northward interplanetary magnetic field.