Abstract
This paper gives a description of a narrow-hand near-infrared radiometer that was operated during the marine stratocumulus intensive field observation program of FIRE in 1987 from the United Kingdom Meteorological Office C130 aircraft. All data with small solar zenith angles and continuous stratocumulus sheets have been analysed. A method to determine cloud optical depth and effective radius of the drop size distribution is presented from both reflectance and transmittance data. The data demonstrate that different cloud droplet sizes were successfully distinguished and realistic optical depths were obtained. Absolute comparison with in situ droplet effective radii measurements showed an inconsistency, remotely retrieved values being up to 50% larger than the in situ values.