A minimalist bulk stratocumulus - trade cumulus boundary layer model

Marine stratocumulus clouds exert a strong influence on the Earth radiation budget and climate. Shallow cumulus convection is an important process regulating the characteristic structures of temperature, moisture, and momentum of the trades, and often interacts with stratocumulus clouds. Previous studies explored the structure of stratocumulus and trade cumulus boundary layers using various types of bulk models, but the assumptions involved in their models are rather complex and caused some inconsistencies. In this study, we construct a fully-consistent, minimal complexity bulk stratocumulus - trade cumulus boundary layer model that has similar dynamic assumptions to typical parameterizations based on a single entraining-detraining cumulus updraft plume growing under a radiatively-driven stratocumulus-topped mixed layer. Then, we investigate some issues of fundamental importance for understanding and parameterizing stratocumulus - trade cumulus cloud fields over the ocean.