Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
Main Title Extended Analysis of the CARES Aerosol Chemistry Data to Characterize Sources and Processes of Organic Aerosol in the Sacramento Valley of California.
Author Q. Zhang
CORP Author California Univ., Davis. Dept. of Environmental Toxicology.; California State Air Resources Board, Sacramento.; California Environmental Protection Agency, Sacramento.
Year Published 2014
Report Number CARB-10-305
Stock Number PB2014-105978
Additional Subjects Aerosols ; Air pollution sources ; California ; Air pollution monitoring ; Atmospheric chemistry ; Emissions ; Particles ; Physical properties ; Plumes ; Sulfates ; Urban areas ; Weather ; Carbanaceous Aerosols and Radiative Effects Study(CARES) ; Sacramento Valley(California)
Library Call Number Additional Info Location Last
NTIS  PB2014-105978 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 09/17/2014
Collation 93p
This report explores the characteristics, sources, and processes of submicrometer particles in northern California via integrated analyses of atmospheric observation data obtained during the Carbonaceous Aerosols and Radiative Effects Study (CARES) that took place in northern California in June 2010. We focus on reporting aerosol chemistry, physical properties, and diurnal and temporal variations at Cool (denoted as the T1 site of the project) at the foothills of the Sierra Nevada Mountains, where intense biogenic emissions are periodically mixed with urban outflow transported by daytime southwesterly winds from the Sacramento metropolitan area. During CARES, the average mass loading of submicrometer particles (PM1) was 3.0 ig m- 3, dominated by organics (80%) and sulfate (9.9%). The organic aerosol (OA) had a nominal formula of C1H1.38N0.004O0.44, thus an average organic mass-to-carbon (OM/OC) ratio of 1.70. Three OA types were identified by PMF analysis of the high resolution mass spectra: two different OOA components (90% of total organics) and a HOA (10%). The more oxidized MOOOA (O/C = 0.54) was identified as biogenically influenced SOA, while the less oxidized LOOOA (O/C = 0.42) corresponded to anthropogenically influenced SOA (e.g., from the Sacramento area). The HOA factor corresponded mainly to primary emissions from local traffic. On average, SOA (= MO-OOA + LO-OOA) accounted for 91% of the total OA mass and 72% of the PM1 mass observed at Cool. Twenty three periods of urban plumes from T0 (Sacramento) to T1 (Cool) were identified using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem).