Properties of clouds and the cloud transition zone retrieved from ship-borne hyperspectral observations during MAGIC

The Marine ARM GPCI Investigation of Clouds (MAGIC) field campaign was conceived, in part, to improve our understanding of the stratocumulus to cumulus cloud transition. The MAGIC campaign was operated aboard the Horizon Spirit, a commercial shipping vessel, by the DOE's Atmospheric System Research (ASR) program. ASR's second mobile facility was aboard the Spirit from October 2012 to September 2013, operating in the Pacific Ocean between Los Angeles, CA and Honolulu, HI. Beginning in July 2013, the Solar Spectral Flux Radiometer (SSFR), a hyperspectral radiometer, was included with the scientific payload. The SSFR is a medium resolution spectrometer with a spectral range from 350 nm to 1700 nm that operates at 1 Hz. The spectral and temporal resolution of the SSFR make it ideal for cloud studies. We present the retrieval results of cloud optical thickness and effective particle radius under overcast skies using the SSFR data. In addition, using a newly developed algorithm, we also explore the variability of cloud properties in the cloud transition zone, the region between cloudy and cloudless skies.