title: Aerosol species concentrations and source apportionment of ammonia at Rocky Mountain National Park.
abstract: Changes in ecosystem function at Rocky Mountain National Park (RMNP) are occurring because of emissions of nitrogen and sulfate species along the Front Range of the Colorado Rocky Mountains, as well as sources farther east and west. The nitrogen compounds include both oxidized and reduced nitrogen. A year-long monitoring program of various oxidized and reduced nitrogen species was initiated to better understand their origins as well as the complex chemistry occurring during transport from source to receptor. Specifically the goals of the study were to characterize the atmospheric concentrations of nitrogen species in gaseous, particulate, and aqueous phases (precipitation and clouds) along the east and west sides of the Continental Divide; identify the relative contributions to atmospheric nitrogen species in RMNP from within and outside of the state of Colorado; identify the relative contributions to atmospheric nitrogen species in RMNP from emission sources along the Colorado Front Range versus other areas within Colorado; and identify the relative contributions to atmospheric nitrogen species from mobile sources, agricultural activities, and large and small point sources within the state of Colorado. Measured ammonia concentrations are combined with modeled releases of conservative tracers from ammonia source regions around the United States to apportion ammonia to its respective sources, using receptor modeling tools.
authors.affiliation: Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, Colorado 80523-1375, USA. malm@cira.colostate.edu
authors.forename: William C
authors.initials: WC
authors.lastname: Malm
authors.affiliation: Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, Colorado 80523-1375, USA.
authors.forename: Bret A
authors.initials: BA
authors.lastname: Schichtel
authors.affiliation: National Park Service, Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, Colorado 80523-1375, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Barna
authors.affiliation: National Park Service, Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, Colorado 80523-1375, USA.
authors.forename: Kristi A
authors.initials: KA
authors.lastname: Gebhart
authors.affiliation: AECOM, Fort Collins, Colorado, USA.
authors.forename: Marco A
authors.initials: MA
authors.lastname: Rodriguez
authors.affiliation: Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80523-1375, USA.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Collett
authors.affiliation: AECOM, Fort Collins, Colorado, USA.
authors.forename: Christian M
authors.initials: CM
authors.lastname: Carrico
authors.affiliation: Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80523-1375, USA.
authors.forename: Katherine B
authors.initials: KB
authors.lastname: Benedict
authors.affiliation: Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80523-1375, USA.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Prenni
authors.affiliation: Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80523-1375, USA.
authors.forename: Sonia M
authors.initials: SM
authors.lastname: Kreidenweis
mesh_terms: D000336:Aerosols / Q000737:chemistry*; D000393:Air Pollutants / Q000737:chemistry*; D000641:Ammonia / Q000032:analysis*; D003120:Colorado; D008962:Models, Theoretical
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D000641:Ammonia