Mesopause temperature observed by airglow OH spectra and meteor echoes at Shigaraki (34.9°N, 136.1°E), Japan Original Research Article

Simultaneous measurements of the airglow OH(6,2) band spectra by a sky scanning spectrophotometer and meteor echoes by the MU radar were carried out at Shigaraki (35° N, 136° E), Japan, during July 24–30, 1995. The spectrophotometer observed the P1(2) and P1(4) line intensities and derived rotational temperature, TOH, in 8 cardinal points in the sky with a time sequence of 6 minutes. The MU radar was operated in a meteor radar mode, observing wind velocities and ambipolar diffusion coefficient. From the diffusion coefficient the relative temperature fluctuations, TMU, were derived in a height range of 75 – 100 km, with a time resolution of 12 hour. We found that there is, in general, good agreement in the nocturnal variation between the TOH and TMU, indicating effectiveness of the parameter TMU to monitor temperature variation in the mesopause region.