Observed extinction by clouds at 95 GHz

Measurements were made in maritime stratus with a 95 GHz pulsed Doppler radar mounted on an aircraft. The aircraft also carried in situ probes for characterization of the cloud composition in terms of liquid water content (LWC) and size distribution of the hydrometeors. Flight segments of 5-10 km length were selected for analysis over which the LWC was relatively uniform. Mean values of LWC ranged from 0.05 to 0.8 g/m/sup 3/. The dominant part of the LWC came from droplets smaller than 50 /spl mu/m diameter. The temperature was near +10/spl deg/C for all cases, and the pressure was near 900 mb. After correcting for extinction by water vapor, the observations yielded an extinction coefficient of 4.6 dB/km per g/m/sup 3/ of cloud water. This result agrees with theoretical values and constitutes the first direct test of those calculations.