Cloud Scavenging Effects on Aerosol Radiative and Cloud-nucleating Properties - Final Technical Report

Ogren, John A. ; Sheridan, Patrick S. ; Andrews, Elisabeth

关键词: ABSORPTION;    AEROSOLS;    ALBEDO;    CHEMICAL COMPOSITION;    CLIMATE MODELS;    CLOUDS;    DISTRIBUTION;    INTERSTITIALS;    LIFETIME;    LIGHT SCATTERING;    OPTICAL PROPERTIES;    PROCESSING;    SCATTERING;    SCAVENGING aerosol;    cloud;    climate;   

DOI  :  10.2172/948732
RP-ID  :  DOE/ER/64576-FIN
PID  :  OSTI ID: 948732
Others  :  Other: 3RR1MCSPEN
Others  :  TRN: US201005%%277

学科分类：环境科学（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

The optical properties of aerosol particles are the controlling factors in determining direct aerosol radiative forcing. These optical properties depend on the chemical composition and size distribution of the aerosol particles, which can change due to various processes during the particles’ lifetime in the atmosphere. Over the course of this project we have studied how cloud processing of atmospheric aerosol changes the aerosol optical properties. A counterflow virtual impactor was used to separate cloud drops from interstitial aerosol and parallel aerosol systems were used to measure the optical properties of the interstitial and cloud-scavenged aerosol. Specifically, aerosol light scattering, back-scattering and absorption were measured and used to derive radiatively significant parameters such as aerosol single scattering albedo and backscatter fraction for cloud-scavenged and interstitial aerosol. This data allows us to demonstrate that the radiative properties of cloud-processed aerosol can be quite different than pre-cloud aerosol. These differences can be used to improve the parameterization of aerosol forcing in climate models.