Solar radiative transfer is treated in a three-layer cloudy-aerosol atmosphere located over a Lambertian reflecting underlying surface. Mathematical expectation and variance of the intensity of reflected solar radiation, modulated by broken clouds, are investigated as functions of the cloud optical parameters, cloud type, solar zenith angle, and albedo of the underlying surface. It is shown that the effects caused by random geometry of cloud field may produce significant quantitative and qualitative differences in the mathematical expectation and variance of radiation intensity in cumulus and stratus clouds.