Simulation of Diurnal Variation in a Stratocumulus-capped Marine Boundary Layer during FIRE

Abstract

A model simulation is presented of the diurnal cycle of a marine stratocumulus-capped boundary layer. The model results are compared with observations obtained during the 1987 First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment marine stratocumulus project, made from San Nicolas Island, off the coast of California. Both the simulation and the observations show a marked diurnal variation in cloud properties, as a result of the decoupling of the boundary layer into a separate cloud and a subcloud layer. In the model simulation the decoupling is caused by the absorption of the solar radiation in the cloud layer.