AIRBORNE RETRIEVAL OF CIRRUS CLOUD OPTICAL AND MICROPHYSICAL PROPERTIES USING AIRBORNE REMOTE EARTH SENSING SYSTEM 5.1-5.3 AND 3.7-MU-M CHANNEL DATA

We present an airborne retrieval algorithm to infer cirrus cloud tempe rature, optical depth, and mean effective sizes using the Airborne Rem ote Earth Sensing System (ARES) hyperspectral spectrometer data for th e 5.1-5.3 and 3.7 mu m channels. The algorithm, development and the se lection of the channels are based on the principle and parameterizatio n of radiative transfer involving cirrus clouds and the associated atm ospheric and surface properties. It has been applied to a selected cas e of the ARES data collected over the western Boston area on September 16, 1995. Validation of the retrieved parameters was carried out usin g the collocated and coincident ground-based 8.6-mm radar data and ice crystal size distribution measurements obtained from the 2D-P probe o n board the high-altitude reconnaissance platform (HARP). We show that the retrieved cirrus cloud temperature, mean effective ice crystal si ze, and optical depth match closely with those derived from the observ ations.