A high-latitude 8-hour wave in the mesosphere and lower thermosphere

We used simultaneous multimission Fabry Perot interferometer neutral wind, airglow intensity, and temperature observations at Resolute (75°N) and meteor radar neutral wind observation at Esrange (68°N) to study a wave event with a period of close to 8 hours. On the basis of two days' worth of observations in October, we were able to show that during this event the 8-hour wave only appeared at Resolute (75°N) and damped from 87- to 97-km altitude with a vertical wavelength of ∼35 km. The OH emission temperature 8-hour oscillation was leading that in the OH emission brightness, resulting a negative phase of Krassovsky ratio, which may be related to the damping of the wave. The 8-hour wave also appears to be affected by planetary waves, resulting in a small phase shift for the wave from the first to the second day.