Fine particulate matter measurements during the Houston Fine Particulate Matter Supersite Program
Abstract
The Gulf Coast Aerosol Research and Characterization Program (GC-ARCH) was established in southeast Texas as one of USEPA's fine particulate matter supersite programs. This 16-month program started in August 2000 (in parallel with the Texas Air Quality Study) and added several monitoring sites for particulate matter to the existing network in Texas. There are 62 sites statewide that have measured total PM2.5 mass (19 in southeast Texas) according to the federal reference methods (FRM) since 1999. Samples from 13 sites (8 in southeast Texas) have also been subject to chemical speciation to determine the composition of fine particulate matter in the state. In addition to FRM monitoring, several continuous TEOM monitors continuously measure PM2.5 mass in the state. This paper presents an overview of the FRM PM2.5 data, the chemical speciation PM2.5 data and the TEOM data in Texas. This analysis complements data from a 1997-1998 PM2.5 study performed by the Houston Regional Monitoring Network and PM2.5 chemical composition data by other researchers from GC-ARCH. The findings are the first step in establishing a conceptual model for PM2.5 formation in Texas. There are strong diurnal patterns observed in PM2.5 mass at sites in southeast Texas that may not be reflected in the 24-hour average FRM data. The predominant chemical components of PM2.5 throughout the state are sulfates and organic carbon. Ozone season PM2.5 levels tend to be higher in total mass but also in the major components: sulfates and organic carbon. This suggests that the secondary components of PM2.5 are important contributors to elevated PM2.5 levels. Both the FRM data and TEOM also reflect strong primary source influences when biomass burning is known to occur in the region.
- Publication:
-
AGU Spring Meeting Abstracts
- Pub Date:
- May 2002
- Bibcode:
- 2002AGUSM.A21C..08A
- Keywords:
-
- 0305 Aerosols and particles (0345;
- 4801);
- 0365 Troposphere: composition and chemistry