Non-precipitating stratus cloud characterization using a ground-based dual-wavelength millimeter Doppler radar

Better insights into the microphysical structure of clouds will be helpful to improve several meteorological models for the hydrometeor distribution within clouds. Stratus clouds were studied using a dual-frequency radar operating at 33 and 95 GHz. These clouds are found in the lower part of the atmosphere and have a profound impact on the Earth's radiative budget because of their high albedo and large global coverage. Stratus clouds are difficult to study with visible and IR sensors due to their high optical extinction rate. Cloud properties were retrieved including their suspended-water droplet size distribution and the liquid water content using UMass' Cloud Profiling Radar System. Data from radiosonde observations was used for the gaseous attenuation correction. Radar reflectivity modifications to consider the effect of the wind speed, the difference of beamwidth at both frequencies and the difference in sampled range cells are checked and corrected when necessary. A new way of estimating D₀ and N₀ values is presented.