Abstract
The laser radar system at Kingston, Jamaica (189N, 17°W) has been used to study periodic variations in atmospheric density at altitudes between 68 and 100 km. A major feature of these variations is an oscillation with a vertical wavelength of 12–14 km, descending phase, and a probable period of 24 h. This has been identified as the θ3ω,1 atmospheric tidal oscillation and a comparison of its observed characteristics with theoretical predictions for this tidal mode shows good agreement.