Winds and waves in the middle atmosphere as observed by ground-based radars

Ground-based radars have proved to be powerful instruments for studying dynamical processes in the middle atmosphere. They have been used successfully in the last few years during Pre-MAP and MAP projects. This paper briefly reviews the following ground-based radar methods: the new MST radar technique for remote sensing of the mesosphere, stratosphere and troposphere, and the well known techniques for mesospheric measurements such as the ionospheric drift experiment, the meteor radar and the MF radar experiments. A survey of observational results obtained with the various techniques is presented. Particular emphasis is directed to winds and waves as well as their interaction, all of which play an important role in the structure and dynamics of the middle atmosphere.