Physically based parameterization of cirrus cloud formation for use in global atmospheric models

Parameterization for Cloud Longwave Scattering for Use in Atmospheric Models

A parameterization for the scattering of thermal infrared (longwave) radiation by clouds has been developed based on discrete-ordinate multiple-scattering calculations. The effect of backscattering is folded into the emission of an atmospheric layer and the absorption between levels by scaling the cloud optical thickness. The scaling is a function of the single-scattering albedo and asymmetry f...

Parameterization of cloud droplet formation in global climate models

An aerosol activation parameterization has been developed, based on a generalized representation of aerosol size and composition within the framework of an ascending adiabatic parcel; this allows for parameterizing the activation of chemically complex aerosol with arbitrary size distribution and mixing state. The new parameterization introduces the concept of “population splitting”, in which th...

Parameterization of Cirrus Cloud Formation in Large Scale Models : 1 Homogeneous Nucleation

Cloud Parameterization in Global Climate Models: Evaluation with Atmospheric Radiation Measurement Data

The goal of our work is to develop and evaluate a prognostic The aqueous reaction to convert SO to in clouds is aerosol model and to parameterize the effects of aerosols, actassumed to have an average e-folding lifetime of 30 hours at ing as cloud condensation nuclei (CCN), on initial cloud drop40° N at the surface in summer. This e-folding lifetime is let concentrations. This, together with gl...

Continued Development of a Cloud Droplet Formation Parameterization for Global Climate Models