Response of the ionospheric convection reversal boundary at high latitudes to changes in the interplanetary magnetic field

Abstract

AbstractIn this paper we present a systematic study of the location of the convection reversal boundary for southward interplanetary magnetic field by using Defense Meteorological Satellite Program (DMSP) F13 and F15 spacecraft measurements during local summer seasons from 2000 to 2007 for both hemispheres. All the convection reversal boundaries are identified pass bypass by locating the highest‐latitude location where the plasma flow shows a large‐scale two‐cell pattern and reverses direction from sunward to antisunward. The location of the convection reversal boundaries are placed into 10 different categories based on By and the magnitude of southward Bz. Observations suggest that (1) the location of the boundary is well organized by the magnitude of Bz, being at lower latitudes for stronger negative Bz and also organized by the polarity of By, moving toward the dawnside/duskside when By changes from negative to positive in the northern/southern hemisphere; (2) the average latitudinal movement of the boundary associated with By changes is comparable to the average movement of the boundary with Bz changes; (3) an initial reconfiguration of the boundary near local noon is redistributed around the dawnside or duskside dependent on the direction of By; and (4) the boundary has a general spiral shape, which varies depending on Bz and By.