Conjugate Behavior of MSTIDs and ESF Structures

Abstract:

All-sky imagers (ASIs) provide a 2-D view of processes occurring in the upper atmosphere. By focusing in 630.0 nm airglow emissions we can investigate the behavior of ionospheric perturbations related to equatorial Spread-F (ESF) and medium scale travelling ionospheric disturbances (MSTIDs). A significant amount of work related to ESF and MSTIDs has been done in the past using single site ASIs and complementary information from satellite and radar data, with a handful of examples showing studies from both hemispheres. We present results using magnetically conjugate located all-sky imagers in the American sector covering the Caribbean region to southern South America The imagers detect both ESF and MSTIDs and we can sample a region that represents the transition between low latitude and mid latitude physical processes. Complementary information is provided by TEC measurements from GPS receivers. Structures show in general very good conjugate behavior. Local ionosphere-thermosphere background conditions, in particular during solstices, might produce apparent differences in the observations.