The solar and longwave radiative effects of a stratospheric aerosol layer between 18 and 22 km are compared for a tropical atmosphere. The changes in the daily mean solar and longwave radiative fluxes above and below the aerosol layer are computed for two particle size distributions and as a function of the albedo of the earth's surface. The changes in the solar and longwave fluxes above the aerosol layer are found to be comparable in magnitude. In the troposphere, the reduction in the incoming solar radiation (cooling) is several times greater than the increase in the downward longwave radiation (warming), the difference decreasing with increasing surface albedo. Abstract The solar and longwave radiative effects of a stratospheric aerosol layer between 18 and 22 km are compared for a tropical atmosphere. The changes in the daily mean solar and longwave radiative fluxes above and below the aerosol layer are computed for two particle size distributions and as a function of the albedo of the earth's surface. The changes in the solar and longwave fluxes above the aerosol layer are found to be comparable in magnitude. In the troposphere, the reduction in the incoming solar radiation (cooling) is several times greater than the increase in the downward longwave radiation (warming), the difference decreasing with increasing surface albedo.