Magnetically Conjugate Observations of the Low Latitude Ionosphere in Western South America

Abstract:

An all-sky imager (ASI) installed at Villa de Leyva, Colombia (5.6° N, 73.5° W, 16.3° mag lat) in October 2014 is used in conjunction with another ASI near the magnetically conjugate point at El Leoncito in Argentina (31.8° S, 69.3° W, -19.6° mag lat) to study irregularities and perturbations in the ionosphere. A third ASI in Jicamarca, Peru (11.95° S, 76.87° W, 0.1° mag lat) provides context for the structures generated near the magnetic equator on the west coast of South America. The region sampled by these instruments covers from ~40° S to ~15° N and from ~ 80° W to ~65° W . The Jicamarca Radio Observatory has radar systems and other instruments that measure the upper atmosphere which, combined with the ASIs, allow us to uniquely study equatorial and low latitude processes. The ASIs are able to detect airglow depletions at 630 nm associated with equatorial spread F (ESF) that can also observed with coherent radar scatter measurements at Jicamarca. Simultaneous conjugate observations of ESF are compared to see how the large-scale structures behave at these locations. The ASIs are also used to look for a signature of the midnight temperature maximum (MTM) that is seen as an increase in brightness propagating poleward. Radar and Fabry-Perot interferometer data is used to measure this increase in temperature and combining them with the ASI data we will be able to probe the extent of MTM effects and investigate how they vary with latitude in both hemispheres.