Cloud and aerosol effects on the solar heating rate of the atmosphere

Band-by-band calculations are carried out to investigate the solar heating rate and radiative property of the atmosphere containing various combinations of absorbing gases, aerosols and the cloud. The solar spectrum is divided into nine bands according to the location of the absorbing gases which include water vapor, ozone, oxygen and carbon dioxide. The radiation transfer program takes into consideration the inhomogeneity of the cloudy and aerosol atmospheres, the wavelength dependence of solar radiation and the gaseous absorption within scattering layers. A cumulus in the lower troposphere procreates a heating rate as large as 12° C day^-1 when the sun is overhead and generates additional heating rates due to ozone in the lower stratosphere. Aerosols are shown to have a pronounced influence on the heating rate of the lower clear atmosphere, but not for coudy conditions. When the sun is close to horizon, the effect of the cloud on the heating rate is shown to be unimportant. We further illustrate that significant under- and overestimation of the atmospheric absorption and reflection, respectively, would be anticipated if the absorption caused by ozone and oxygen is ignored, particularly in cloudy atmospheres.