An investigation of the characteristics of the convection reversal boundary under southward interplanetary magnetic field

Abstract

The characteristics of the Convection Reversal Boundary (CRB) as determined from Super Dual Auroral Radar Network (SuperDARN) observations of convection are examined and modeled. Convection patterns were calculated for all intervals within the 11 year period 2000-2010 when the interplanetary magnetic field met a restrictive set of criteria. When there were sufficient observations, the CRB was determined and binned as a function of latitude and magnetic local time. There were over 90,000 determinations of the CRB included in the study. Distributions of CRB locations were formed for each hour of magnetic local time. The distributions varied in average latitude and in variance, with the lowest latitude and broadest widths occurring near midnight. The distributions were skewed toward high latitudes on the dayside and toward low latitudes on the night side. The CRB was modeled as a linear sum of terms dependent on the interplanetary magnetic field, the solar wind, and the SymH indices. Finally, the dynamic behavior of the boundary is discussed and modeled in an attempt to reproduce the observed distributions. Key Points Distributions of convection reversal boundary latitudes under steady driving Polar cap is highly variable even under steady driving Latitude distributions can be modeled by a simple model for boundary motion ©2013. American Geophysical Union. All Rights Reserved.