Absorption of solar radiation by stratocumulus clouds: aircraft measurements and theoretical caluclations

Abstract

Aircraft measurements and Monte Carlo calculations showed that spatial inhomogeneities of clouds cause horizontal radiative convergence and divergence, and that vertical radiative convergence - that is, absorptance with a usual definition - apparently becomes extremely large or negative. The apparent absorptance could be corrected by a method that evaluates the true adsorption from the difference between the apparent visible and near-infrared absorptions. The corrected absorptance ageed well with the theoretical absorptance calculated with plane-parallel cloud models. It is also inferred that the anomalous absorption pointed out by aircraft observations in previous studies does not exist. -from Authors