F-region Plasma Drifts at Middle Latitudes Observed by SuperDARN

A greatly expanded network of SuperDARN radars at middle latitudes has been made possible with funding from the National Science Foundation Mid-Size Infrastructure (MSI) opportunity. The completion of four radars in Kansas and Oregon, combined with two existing radars in Virginia, now allow for observation of the convecting plasma above 50 degrees geomagnetic latitude and extending for more than 8 hours in local time. We use observations from these mid-latitude SuperDARN radars during the ascending phase of the recent solar cycle to determine the character of plasma convection in this region that spans the plasmasphere boundary layer (PBL) and extends to auroral latitudes. Observed flows are generally organized by geomagnetic activity level with westward drifts increasing with activity level due to the occurrence of sub-auroral polarization streams (SAPS) and sub-auroral ion drifts (SAIDs). Average convection features are compared for different levels of geomagnetic activity as well as to other empirical models of convection derived from radar and satellite observations.