Ice-cloud depolarization of backscatter for CO[sub 2] and other infrared lidars

Journal Article · Tue Oct 20 04:00:00 EDT 1992 · Applied Optics; (United States)

DOI:https://doi.org/10.1364/AO.31.006485· OSTI ID:6903410

Eberhard, W L ^[1]

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1. Wave Propagation Laboratory, National Oceanic and Atmospheric Administration, R/E/WP2, 325 Broadway, Boulder, Colorado 80303 (United States)

The depolarization of backscatter from ice particles at the CO[sub 2] lidar wavelength of 10.59 [mu]m was investigated through field measurements, with simultanous depolarization measurements taken at 0.6943 [mu]m for comparison. The depolarization ratio at the infrared wavelength was usually at or below the lidar's sensitivity limit of 0.01, which is dramatically smaller than the typical 0.5 linear depolarization ratio for short-wave lidars. This behavior is explained by the strong absorption of ice at the infrared wavelength. Depolarization measurements at a 10.59-[mu]m wavelength cannot discriminate between ice and water clouds in the manner of short-wave lidars. A possibility exists for more prominent depolarization at shorter CO[sub 2] lidar wavelengths (e.g., 9.115 [mu]m), but additional research is required. Depolarization at the 2.09-[mu]m wavelength is predicted to be substantial and useful for hydrometeor observations.

• OSTI ID: 6903410
• Journal Information: Applied Optics; (United States), Journal Name: Applied Optics; (United States) Vol. 31:30; ISSN APOPAI; ISSN 0003-6935
• Country of Publication: United States
• Language: English

Related Subjects

440700* -- Geophysical & Meteorological Instrumentation-- (1990-)
47 OTHER INSTRUMENTATION
BACKSCATTERING
CARBON DIOXIDE LASERS
CLOUDS
DEPOLARIZATION
ELECTROMAGNETIC RADIATION
GAS LASERS
ICE
INFRARED RADIATION
LASERS
MEASURING INSTRUMENTS
OPTICAL RADAR
RADAR
RADIATIONS
RANGE FINDERS
REMOTE SENSING
SCATTERING