Simulation of radiative transfer through broken cloud fields using a stochastic approach

Stochastic radiative transfer theory has been suggested as an approach to representing the macroscale, geometrical features of cloud fields that occur on scales that are notably smaller than the grid size on which climate simulations are made. Scattered cumulus and stratocumulus clouds are examples of naturally occurring cloud fields where stochastic theory may be appropriate. To this end, a stochastic band model is used to investigate radiative transfer through a broken cloud field. The model distributes clouds in a clear sky according to the statistics of the cloud field and then calculates the ensemble-averaged radiation field. 16 days of observations of the macrostructure of cumulus and stratocumulus populations over Oklahoma are ingested by the stochastic model and are used to evaluate the output radiation field. Additionally, a one-dimensional shortwave radiation routine used in many modern general circulation models is used to evaluate the performance of the stochastic model.