PNNL

Abstract

Clouds exert a significant influence on weather and climate by absorbing or reflecting solar radiation. For example, cirrus clouds reflect much of the sunlight back into space. Thus, the cloud effects on radiative fluxes are very sensitive to cloud type, which is characterized by the amount, phase, and size of hydrometeors. In particular, the size of hydrometeors comprising clouds is one of the important factors determining cloud optical depths, but it is typically assumed to be a function of temperature and surface type, or it is roughly estimated with a radiation scheme in most models. Recently, researchers tried to study proper coupling of water substances in microphysics and radiation processes.