CLOUD PHYSICS STUDIES WITH 8-MM WAVELENGTH RADAR

Results from recent cloud experiments with an 8 mm wavelength Doppler radar demonstrate that millimeter wavelength radar can provide importa nt new information about nonprecipitating and lightly precipitating cl ouds. Millimeter wave radar can be used to document small-scale spatia l structure of cirrus and marine stratus clouds. Its data can be used to estimate profiles of ice content, particle size and concentration i n cirrus clouds and profiles of liquid water content and turbulence in marine stratus clouds. New results with mm wave radar suggest that pl ate-like crystals may be distinguishable from aggregates with polariza tion techniques. Quantitative information about cirrus cloud ice cryst al fallspeeds, and therefore ice mass flux, can also be produced with newly developed techniques that exploit the sensitivity and velocity p recision of such radars. The good sensitivity to cloud particles, the immunity from ground clutter contamination, and the good spatial resol ution of millimeter wavelength radar make it an excellent instrument f or documenting quantitative microphysical and dynamical properties of non-precipitating and lightly precipitating clouds.