Development of Gas-Phase Chemistry, Secondary Organic Aerosol, and Aqueous-Phase211 Chemistry Modules for PM Modeling

摘要

The Coordinating Research Council (CRC) is sponsoring a multi-phase study to211u001edevelop improved air quality models for particulate matter (PM). Improved urban 211u001eand regional scale PM air quality models are needed to develop reliable emission 211u001econtrol strategies for areas that exceed the National Ambient Air Quality 211u001eStandards (NAAQS) for PM-2.5 and PM-10, and for National Parks and other Class I 211u001eareas with impaired visibility. This report describes the development and 211u001eimplementation of two process modules for PM models. These particular process 211u001emodules are needed to simulate secondary aerosol species, which are often the 211u001edominate portion of PM-2.5 mass. The first module simulates the gas-phase 211u001eatmospheric chemistry of the VOC/NOx/SO2/ozone system and the formation of 211u001esecondary organic aerosols. The module also simulates the formation of inorganic 211u001especies, including sulfuric acid and nitric acid, that form important aerosol 211u001especies: sulfate and nitrate; The second module simulates the aqueous-phase 211u001echemistry in fogs and clouds. This chemistry primarily enhances SO2 oxidation 211u001erates and leads to enhanced sulfate aerosol concentrations.