Latitude and local time variations of topside magnetic field-aligned ion drifts at solar minimum

Abstract

[1] The movement of ions along terrestrial magnetic field lines frequently causes the redistribution of ionization between northern and southern hemispheres. This behavior is known as interhemispheric transport and is an important source of coupling between the ion and neutral gases in the upper atmosphere. The Communications/Navigation Outage Forecast System (C/NOFS) satellite and the Coupled Ion Neutral Dynamics Investigation (CINDI) provide an opportunity to directly measure ion velocities and ion densities in the topside ionosphere, facilitating the study of the field-aligned ion motions near the equator. Using data from 2008 and 2009, the field-aligned ion velocities shows the presence of and variations in the interhemispheric transport during this extreme solar minimum. Solar local time and corrected magnetic latitude variations in field-aligned plasma transport at equinox and solstice are examined for a fixed longitude region and the consistency or the observed trends are compared to the expected behavior of F region neutral winds.