MEASUREMENT OF STRATUS CLOUD AND DRIZZLE PARAMETERS IN ASTEX WITH A K-ALPHA-BAND DOPPLER RADAR AND A MICROWAVE RADIOMETER

Data are used from a K-alpha-band radar and microwave radiometer along with a droplet model to determine the droplet parameters of drizzle and clouds. Drizzle droplet parameters are determined from the zeroth, first, and second moments of the Doppler spectrum. Cloud droplet parameters are determined from the zeroth moment of the Doppler spectrum and the measured integrated liquid water. Measurements of stratus clouds were made during the Atlantic Stratocumulus Transition Experiment (ASTEX) on the island of Porto Santo in the Madeira Islands, Portugal. Potential applications of this technique would be in the long-term monitoring of stratus clouds and in determining the vertical profiles of cloud liquid water, number of cloud droplets, and modal radius.