Effects of Spectral Dispersion of Cloud Droplet Size Distributions on Radiative Properties of Clouds and Dispersion Forcing

where L is the liquid water content, and ρw is the density of water. In effect, these studies implicitly assume the only effect of aerosols on cloud microphysical properties is to increase N, and re can be parameterized by Eq. (1) for monodisperse droplet size distributions. Eq. (1) has also been used in the parameterization of re. However, available data suggests the spectral shape of the cloud droplet size distribution may also be influenced by the addition of anthropogenic aerosols, and our recent studies, together with others, have shown changes in d have a significant effect on calculation of re (Pontikis and Hicks 1992; Martin et al. 1994; Liu and Hallett 1997; Liu and Daum 2000). This paper expands on these previous studies to address the effect of d on cloud radiative properties, and the role anthropogenic aerosols may have in determining d of marine clouds.