PROJECT SUMMARY/Vali, 9712859/McIntosh, 9713778 Airborne Studies of Clouds and Precipitation with a Millimeter Wavelength Radar Since 1989, with support by the Physical Meteorology Program, the Microwave Remote Sensing Laboratory, at the University of Massachusetts and the Department of Atmospheric Science, at the University of Wyoming have collaborated in the design, development, installation, and application of a 95GHz, airborne, Doppler, polarimetric radar. This award provides further support for development and application of the airborne millimeter-wavelength radar, in combination with in-situ measurements from the King Air Hardware and software improvements to be implemented include addition of selectable filters to match a variety of pulse lengths, use of a new calibration technique to improve the minimum detectable Linear Depolarization Ratio, development of the capability to measure reflectivity at closer range (to improve comparisons with the in-situ probes), and development of a new device to allow switching the beam between fore and aft directions on a pulse-by-pulse basis. Cloud and precipitation research will focus on 1) continued study of Florida cumulus clouds, including contrasting clouds of maritime and continental origins, retrieval of x-z wind cross-sections with a pseudo-dual Doppler merging of the millimeter radar and CP-2 radar data, 2) extension of the Airborne Velocity Azimuth Display method to study wave-like features in Oregon stratus, 3 exploration of polarimetric capabilities, including comparisons of measured and modeled co-polarized and cross- polarized backscafler for different ice-crystal populations, and 4) quantifying the uncertainties associated with measured and predicted reflectivities. In addition, we propose to mount the millimeter-wavelength radar on the French F-27 research aircraft, for pseudo-dual Doppler studies of boundary layer cumulus dynamics in a field observational program in France known as TRAC98. This is n ot only a good international collaboration, but also very cost-effective for the NSF-funded research.
