title: Sensitivity of particulate matter nitrate formation to precursor emissions in the California San Joaquin Valley.
abstract: The formation of secondary ammonium nitrate during the 1995 Integrated Monitoring Study (IMS95) in San Joaquin Valley, CA was investigated using a box model that simulates the atmospheric chemistry and gas/particle partition of inorganic compounds. The concentration of particulate matter (PM) nitrate was found to be sensitive to reductions in VOC emissions. Nitric acid, rather than ammonia, was the limiting reagent in the formation of PM nitrate. The formation of nitric acid was more sensitive to the availability of oxidants than that of NOx. Oxidant chemistry in wintertime conditions in the San Joaquin Valley was shown to be VOC-sensitive. In fact, a decrease in NOx emissions may have the counter-intuitive effect of increasing PM nitrate.
authors.affiliation: Atmospheric and Environmental Research, Inc., 2682 Bishop Drive, Suite 120, San Ramon, California 94583, USA. pun@aer.com
authors.forename: B K
authors.initials: BK
authors.lastname: Pun
authors.forename: C
authors.initials: C
authors.lastname: Seigneur
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D005740:Gases; D009566:Nitrates / Q000032:analysis*; D016877:Oxidants / Q000737:chemistry*; D010316:Particle Size; D012621:Seasons; D014835:Volatilization
chemical_list: D000393:Air Pollutants; D005740:Gases; D009566:Nitrates; D016877:Oxidants; C006568:ammonium nitrate