Ionospheric Plasma Irregularities from Atomic Oxygen Airglow Emissions

Abstract

simultaneous measurements of the atomic oxygen nightglow emissions at 777.4 nm and 630.0 nm have been used in the past few years to determine the ionospheric F-layer peak electron density and peak height, and to investigate the pattem of F-layer depleted plasma regions, or ionospheric transequatorial plasma bubbles, and their associated iregularities in the tropical ionosphere. Meridional scanning observations of these emissions at low latitudes, made with ground- based filter photometers, are presented in the form of computer generated three- dimensional perspective views, showing the spatial north-south and temporal intensity variations of these OI emissions, for both normal conditions and in the presence of magnetic field-aligned large scale plasma iregularities or bubbles. The significant features of these observations are discussed. This remote sensing airglow technique shows to be very useful to study ionospheric plasma dynamical processes and to investigate the pattern and time