Observations of Fine and Coarse Particle Nitrate at Several Rural Locations in the United States

Journal Article · Tue Apr 01 04:00:00 EDT 2008 · Atmospheric Environment, 42(11):2720-2732

DOI:https://doi.org/10.1016/j.atmosenv.2007.05.016· OSTI ID:937372

Lee, Taehyoung; Yu, Xiao-Ying; Ayres, Benjamin; Kreidenweis, Sonia M; Malm, William C; Collett, Jeffrey L

Nitrate comprises an important part of aerosol mass at many non-urban locations during some times of the year. Little is known, however, about the chemical form and size distribution of particulate nitrate in these environments. While submicron ammonium nitrate is often assumed to be the dominant species, this assumption is rarely tested. Properties of aerosol nitrate were characterized at several IMPROVE monitoring sites during a series of field studies. Study sites included Bondville, Illinois (February 2003), San Gorgonio Wilderness Area, California (April and July 2003), Grand Canyon National Park, Arizona (May 2003), Brigantine National Wildlife Refuge, New Jersey (November 2003), and Great Smoky Mountains National Park, Tennessee (July/August 2004). Nitrate was found predominantly in submicron ammonium nitrate particles during the Bondville and San Gorgonio (April) campaigns. Coarse mode nitrate particles, resulting from reactions of nitric acid or its precursors with sea salt or soil dust, were more important at Grand Canyon and Great Smoky Mountains. Both fine and coarse mode nitrate were important during the studies at Brigantine and San Gorgonio (July). These results, which complement earlier findings about the importance of coarse particle nitrate at Yosemite and Big Bend National Parks, suggest a need to more closely examine common assumptions regarding the importance of ammonium nitrate at non-urban sites, to include pathways for coarse mode nitrate formation in regional models, and to consider impacts of coarse particle nitrate on visibility. Because coarse particle nitrate modes often extend well below 2.5 µm aerodynamic diameter, measurements of PM2.5 nitrate in these environments should not automatically be assumed to contain only ammonium nitrate.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 937372
• Report Number(s): PNNL-SA-55403; KP1205030
• Journal Information: Atmospheric Environment, 42(11):2720-2732, Journal Name: Atmospheric Environment, 42(11):2720-2732 Journal Issue: 11 Vol. 42; ISSN ATENBP; ISSN 0004-6981
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AERODYNAMICS
AEROSOLS
AMMONIUM NITRATES
DISTRIBUTION
IMPROVE
MONITORING
MOUNTAINS
NATURE RESERVES
NITRATES
NITRIC ACID
PARTICULATES
PM2.5
SEAS
SOILS
VISIBILITY
acidity
coarse particle
nitrate
visibility