Science Inventory

SCIENCE VERSION OF PM CHEMISTRY MODEL

Impact/Purpose:

1. Using laboratory and field study data generated during FY99-FY04, develop a science version of a PM chemistry model for predicting ambient concentrations of water, inorganics, and organics in PM2.5 samples. The model will include the Aerosol Inorganic Model for predicting concentrations of inorganic compounds and a computational chemistry-based method for predicting concentrations of organic compounds.

2. Identify and evaluate methods for analyzing the polar fraction of PM2.5 samples.

3. Carry out short term field studies in Research Triangle Park, North Carolina in the summer and the winter to determine the composition of the organic fraction of ambient PM2.5 samples, with special emphasis placed on identifying and determining ambient concentrations of polar compounds.

4. Conduct laboratory studies to establish the chemical composition of secondary organic aerosol (SOA) and to determine source signatures for aromatic and biogenic SOA.

5. Conduct laboratory and theoretical investigations of thermodynamic properties of polar organic compounds.

6. Evaluate the science version of the PM chemistry model using laboratory and field data generated under this task as well as other available data in the literature.

7. Conduct PM chemistry-related special studies for OAQPS

Description:

PM chemistry models containing detailed treatments of key chemical processes controlling ambient concentrations of inorganic and organic compounds in PM2.5 are needed to develop strategies for reducing PM2.5 concentrations. This task, that builds on previous research conducted in this laboratory, will focus on developing the science version of a PM chemistry model (FY04 APM222), that after simplification and evaluation will be used by EPA and the States as a regulatory PM chemistry model to predict ambient PM2.5 concentrations. The research task will also include theoretical and laboratory investigations of thermodynamic properties of polar organic compounds, key constituents of the organic fraction of PM2.5. Furthermore, laboratory and field studies will be carried out to collect data for developing and evaluating the model, with special laboratory studies focusing on identifying chemical marker compounds for determining the contributions of biogenic and aromatic compounds to ambient PM2.5 concentrations. During the field studies, emphasis will be placed on identifying and determining the concentrations of polar organic compounds in PM2.5. Finally, special studies will be carried out for OAQPS to address atmospheric chemistry issues affecting the NOx transport rule and implementation of the PM2.5 NAAQS.

Record Details:

Record Type:PROJECT
Start Date:10/01/2001
Completion Date:09/01/2004
Record ID: 56077