Title :
Observed extinction by clouds at 95 GHz
Author :
Vali, Gabor ; Haimov, Samuel
Author_Institution :
Dept. of Atmos. Sci., Wyoming Univ., Laramie, WY, USA
Abstract :
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 3. The dominant part of the LWC came from droplets smaller than 50 μm diameter. The temperature was near +10°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/m3 of cloud water. This result agrees with theoretical values and constitutes the first direct test of those calculations
Keywords :
Doppler radar; airborne radar; clouds; electromagnetic wave absorption; electromagnetic wave scattering; meteorological radar; millimetre wave propagation; remote sensing by radar; tropospheric electromagnetic wave propagation; 10 degC; 50 micron; 900 mbar; 95 GHz; clouds; droplets; extinction; extinction coefficient; hydrometeors; liquid water content; maritime stratus; pressure; size distribution; temperature; water vapor; Aircraft; Attenuation; Clouds; Doppler radar; Extinction coefficients; Radar antennas; Radar cross section; Radar imaging; Radar measurements; Reflectivity;
Conference_Titel :
Geoscience and Remote Sensing Symposium Proceedings, 1998. IGARSS '98. 1998 IEEE International
Conference_Location :
Seattle, WA
Print_ISBN :
0-7803-4403-0
DOI :
10.1109/IGARSS.1998.702819
