Parameters derived from spectral analysis of radar signals, viz. their strength, Doppler shift, and Doppler spread, contain information about winds and turbulence in the atmosphere. Further statistical analyses of time and spatial series of these parameters in turn provide information about atmospheric wave phenomena influenced by gravity, interactions of these waves with winds, and about their eventual breakdown into small scale chaotic or turbulent motions. The mechanisms through which radar signals are scattered by turbulence and optimum techniques for deriving most useful parameters from these signals are also of significant interest for designing radar experiments. Several middle atmosphere radar facilities have been constructed in the U.S., Japan, West Germany, and Scandinavia. We continue to have access to some of these radar facilities for designing and conducting new experiments, and to data collected with them. Efforts at Case Western Reserve University (CWRU) are directed towards the statistical signal processing of radar and rawinsonde data tapes, sophisticated graphical displays of results, interpretation of these results in terms of fluid wave and turbulence phenomena in the atmosphere, and on mechanisms of interactions between atmospheric turbulence and the probing radio waves. It is anticipated that over the next three years about 7-8 MS and 2-3 Ph.D. theses could be supported with the purchase of the data processing and graphics equipment provided by this grant.
