Remote sounding of high clouds. Part VI: optical properties of midlatitude and tropical cirrus.

Abstract

A lidar (0.694 micro m wavelength) and a passive radiometer (10-12 micro m) have been used together to remotely sense the optical properties and gross structure of cirrus (the LIRAD method) . This article reports on observations of midlatitude cirrus taken during 2 extended experiments at Aspendale, Victoria, Australia, covering one winter season and one summer season and a 6 week period of observations to tropical cirrus at Darwin, Northern Territory. Information has been obtained on the infrared emittance, optical depth, cloud depth, depolarization ratio, 'anomalous' backscatter, the effective ratios of backscatter to extinction at the lidar wavelengths and the visible to infrared extinction, and the backscatter profile of cirrus.-from Authors