Reflection of Solar Radiation from an Array of Cumuli

Abstract

The solar radiation reflected by an array of finite broken clouds corresponding to cumuli is examined. The importance of the distribution of cloud size is demonstrated by using the actual cloud pattern ove Florida. The accuracy of simplified cloud models (plane-parallel infinite cloud or an array of identical clouds) to approximate the array of clouds with size distribution is examined. The result shows the following: (1) The model of plane-parallel infinite cloud causes fairly large error in the reflection. (2) The model of the array of identical clouds is still insufficient to approximate the array of distributed clouds. (3) When the sun is high, the difference between the models of cloud array becomes most evident and an accurate model for broken clouds is required. (4) The result of (3) is maintained even if the reflection from the clouds-earth surface system is considered.