Observations of variations in airglow emissions during ALOHA‐93

Abstract

Observations have been made of the OH Meinel and O 2 Atmospheric intensity and temperature on 8 nights of ALOHA‐93. These data show the presence of diurnal and semidiurnal tides in the 85 to 95 km region whose amplitudes are much greater than were predicted. The signature of a 6 hour tide was also observed at least in the region above 90 km. The magnitudes of the gravity‐wave induced airglow fluctuations were at least as great or greater than were observed during ALOHA‐90. These fluctuations however were in general less than half the magnitude of the combined tidal amplitudes. One unusual observation was of airglow intensity increasing without an accompanying apparent increase in temperature. This is an indication of a non‐periodic change in atmospheric composition near the mesopause.