OBSERVATIONS OF ATMOSPHERIC WAVES FROM GROUND-BASED AIRGLOW MEASUREMENTS

Abstract

Lower thermospheric and upper mesospheric temperatures have been estimated from ground-based measurements of the O2(0-1) and OH(6-2) emission over Resolute (74.68°N, 94.90°W) and OH(4-2) over Kiruna (67.90°N, 21.10°E). During the observation period in November, 2001, dominant and coherent 4-hr oscillations were observed in both the O2 and OH airglow brightnesses and rotational temperatures. This is probably the first time that a dominant 4-hr wave has been studied with multi-station data sets. These two cases provide a good opportunity for us to characterize the high latitude 4-hr wave by least squares fitting and spectral analysis. The reasonable explanation for the observed 4 hr oscillations presented here may be either gravity waves or zonally symmetric tidal origin, because the amplitudes of the Hough modes for migrating tides vanish at the poles. Other sources such as polar cap electrodynamics, aurora cannot be ruled out.. The long-term monitoring of O2 and OH emissions at Resolute is planned and will provide further explanation in the future.