A model to predict cloud density from midlatitude atmospheric soundings for microwave radiative transfer applications

A new model for computing cloud liquid density from vertical profiles of meteorological variables, provided by either radio soundings or atmospheric analyses, is proposed. It has been developed for local-scale applications, in particular for a midlatitude environment such as the Mediterranean area, although the methodology can be easily extended to other climatic zones. The model has been derived from a numerical simulation of a cloudy event that occurred in the Mediterranean basin, performed by means of a microphysical mesoscale meteorological simulation package. The validation has been mainly carried out through a comparison between brightness temperature simulations in cloudy conditions and satellite microwave radiometric data over the Mediterranean Sea. The simulations have been performed by applying a radiative transfer scheme to a set of atmospheric profiles consisting of both European Centre for Medium-Range Weather Forecasts (ECMWF) analyses and radiosonde measurements. Two literature models have been considered as benchmarks. The new model reproduces the Special Sensor Microwave Imager brightness temperature statistics in the Mediterranean area fairly well. Furthermore, it predicts an integrated liquid water content which is in agreement with that supplied by the ECMWF analyses.