Development of Parameterizations of the Effects of Heterogeneous Cloud Chemistry on the Radiative and Water Activity Properties of Aerosols in Mesoscale Models

9526402 Hegg大气气溶胶粒子被认为通过散射和吸收入射太阳辐射直接影响地球的辐射平衡，或者通过改变云的微物理特性间接影响地球的辐射平衡。本项目探讨了非均相硫酸盐化学对云滴数浓度和大小分布的影响（气溶胶间接效应）。该研究使用计算机建模来开发云非均相化学对云处理硫酸盐气溶胶的光学和水活性特性影响的参数化。参数化利用传递函数来估计一系列预测变量的影响，这些预测变量是标准的大块参数化云模型的组成部分。区域尺度模拟方法是评估云非均相化学对云凝结核（CCN）和光学性质影响的一种新方法，目前现有的全球气候模式（GCMs）无法对其进行改进。该项目的结果将提供必要的改进，使目前的模式能够在区域尺度上生成云/气溶胶相互作用的实际处理方法。该参数化研究将是为GCM开发类似参数化的关键、基本步骤。

9526402 Hegg Atmospheric aerosol particles are believed to influence the earth's radiation balance either directly by scattering and absorbing incoming solar radiation, or indirectly by altering cloud microphysical properties. This project addresses the effects of heterogeneous sulfate chemistry on cloud droplet number concentrations and size distributions (the aerosol indirect effect). The study uses computer modeling to develop a parameterization of the impact of cloud heterogeneous chemistry on the optical and water active properties of cloud-processed sulfate aerosols. The parameterization utilizes a transfer function to allow estimation of the impact from an array of prognostic variables that are components of standard, bulk-paramerized cloud models. The regional scale modeling approach is a new method for evaluating the influence of cloud heterogeneous chemistry on cloud condensation nuclei (CCN) and optical properties, a refinement not currently possible with existing global climate models (GCMs). The results from the project will provide needed improvements in the current ability of models in generating realistic treatments of cloud/aerosol interactions on a regional scale. This parameterization study will be a key, fundamental step in developing similar parameterizations for GCM's.