Vol. 11, No. 1, 52-63, 2012

Abstract
Aerosol particles exert important influences on climate and climate change by scattering and absorbing solar radiation and by influencing the properties of clouds. The aerosol life cycle determines the spatial and temporal distribution of atmospheric particles and their chemical, microphysical, and optical properties, which in turn determines the earth radiation budget. In this paper, we investigate the performance of the atmospheric model CMAQ 4.71 (Community Multiscale Air Quality) currently used by the Department of Environmental Conservation (DEC) to provide regional pollution forecasts and analysis. We focus on the use of remote sensing tools to better understand the modifications of the optical properties of aerosols as a function of relative humidity, size-distributed composition and sulphate content. In doing this, a novel technique is used to calculate the comparison of optical parameters, such as extinction, backscatter and aerosol optical depth. This, in turn, is used on the CMAQ 4.7.1 model outputs to be compared with concentrations of PM2.5 (particulate matter less than 2.5 μm in size) measured with TEOM (Tapered element oscillating microbalance), with sunphotometer measurements of AOD (aerosol optical depth) and with multiwavelength lidar-derived backscatter and extinction profiles.