Multiangle observations of Arctic clouds from FIRE ACE: June 3, 1998, casestudy

In May and June 1998 the Airborne Multiangle Imaging Spectroradiometer (Air MISR) participated in the FIRE Arctic Cloud Experiment (ACE). AirMISR is an airborne instrument for obtaining multiangle imagery similar to that of th e satellite-borne MISR instrument. This paper presents a detailed analysis of the data collected on June 3, 1998. In particular, AirMISR radiance meas urements are compared with measurements made by two other instruments, the Cloud Absorption Radiometer (CAR) and the MODIS airborne simulator (NIAS), as well as to plane-parallel radiative transfer simulations. It is found th at the AirMSR radiance measurements and albedo estimates compare favorably both with the other instruments and with the radiative transfer simulations . In addition to radiance and albedo, the multiangle AirMISR data can be us ed to obtain estimates of cloud top height using stereoimaging techniques. Comparison of AirMISR retrieved cloud top height (using the complete MISR-b ased stereoimaging approach) shows excellent agreement with the measurement s from the airborne Cloud Lidar System (CLS) and ground-based millimeterwav e cloud radar.