The impact of surface albedo on the retrievals of low-level stratus cloud properties: An updated parameterization

An updated version of Dong et al. (1998, hereinafter referred to as D98) parameterization is developed from a total of 40 hours of data with a broad range of surface albedos (0.1-0.8) during the 2000-2002 winter seasons at the DOE ARM SGP site. The updated parameterization includes the impact of surface albedo on the retrievals of stratus cloud microphysical and radiative properties, and has a significant improvement over D98 when surface albedo is high. Comparing the retrievals, the cloud-droplet effective radii (r_e) calculated from the updated parameterization have a higher correlation coefficient (0.733) and lower Root-Mean-Square (RMS) error (1.74 μm or 17.4%) than those (0.602, 4.0 μm or 40%) from the D98. The cloud albedos also have a much higher correlation coefficient (0.983) and lower RMS (3%) than those (0..465, 26%) from the D98. The upper limit of surface albedo is 0.3 in applying the D98.