Remote sounding of high clouds. IV: observed temperature variations in cirrus optical properties ( Aspendale).

Abstract

The results of a ruby lidar (0.694 micrometre wavelength) and infrared radiometer (10-12 micrometre) study on cirrus clouds are reported for a period covering the autumn and winter months at Aspendale (38oS, 144oE). The lidar and radiometer data have been used to study the temperature dependence of the gross structure and optical properties of cirrus clouds. Well-defined correlations are found between the mid-cloud temperature and cloud depth, infrared absorption coefficient, infrared emittance, backscatter to extinction ratio and ratio of the visible extinction coefficient at 0.693 micrometre to the infrared absorption coefficient at 10-12 micrometre. -from Authors