Wind and waves in the middle atmosphere observed with the MU radar

The VHF band MU radar at Shigaraki, Japan, has been in full operation successfully since April 1985. Dynamical features found primarily in the data obtained by the radar during a one year period from December 1985 to November 1986 are examined. These include: basic wind observations, quasi-monochromatic gravity waves generated by the jet stream or through a geostrophic adjustment process, seasonal variation of the mesoscale wind variability, the momentum flux due to gravity wave motions, and saturated gravity wave spectrum. A short discussion is added to the relationship between turbulent layers and ambient wind field in the mesosphere.