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

Abstract

[1] 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.Citation: Pierdicca, N., L. Pulvirenti, and F. S. Marzano (2006), A model to predict cloud density from midlatitude atmospheric soundings for microwave radiative transfer applications, Radio Sci., 41, RS6005,

Cloud liquid models for propagation studies: Evaluation and refinements

“…Figure 10. Scatterplots of TBs at 31.65 from the MWR2 vs simulated TBs from radiosondes applying the ARPS-derived cloud liquid model [5]. The analysis of the results indicates that the various models provide comparable results at the site of Pomezia, with an rms ranging from 4.7 to 5.4 K for all the models.…”

“…Scatterplots of T B s at 31.4 GHz measured from the MWR vs simulated TBs from radiosondes applying the model proposed in [5].…”

“…2 was set to 1.5, since it provided the best results in Section 6.1. Concerning the exponential decay of the liquid water content with the decrease of temperature found in [5], (see also Section 7) we have also included in our analysis the following function for the liquid fraction f 2w :…”

“…A new cloud density model has been proposed based on the outputs of a numerical simulation of a cloudy event, derived from a meso-scale forecast system with explicit cloud microphysics [5]. The simulation has been carried out by means of the Advanced Regional Prediction System (ARPS) [6,7], which is a non-hydrostatic mesoscale numerical model that has shown good accuracy in predicting cloudy events occurring at the Mediterranean latitudes.…”

“…A novel approach for computing cloud liquid density from an atmospheric vertical profile is also analyzed. A new cloud liquid model has been derived by Piedicca et al [5], based on the outputs of numerical simulations of a cloudy event occurred in the Mediterranean basin, and performed by means of a meso-scale forecast system with explicit cloud microphysics [6,7]. In this work, we validate the model at the site of Pomezia, since it has been developed for a mid-latitude environment.…”