Atmospheric Reactive Nitrogen in Northern Colorado

Katherine Benedict1, Yixing Shao2, Amy P. Sullivan3, Yi Li4, Evelyn Bangs5, Bret A. Schichtel6 and Jeffrey L. Collett Jr.7

Ammonia emissions in northeastern Colorado impact sensitive ecosystems in Rocky Mountain National Park (RMNP).  The spatial distribution of ammonia in the region and specific transport pathways are uncertain. It is important to understand the degree to which these different urban and agricultural sources impact RMNP, and how various meteorological conditions are associated with high-deposition periods in the park. Ongoing measurements at RMNP include 24hr-integrated gaseous and particulate nitrogen species measured by denuder/filter pack methods, high-time resolution gaseous ammonia, and wet deposition of nitrogen compounds.  Research in RMNP has been combined with measurements in the Front Range and eastern Plains of Colorado to better understand the movement of ammonia from source regions to the alpine ecosystems of RMNP. Here we present observations from high-time resolution ammonia instruments across an east-west transect as well as mobile observations that provide a snapshot of the spatial distribution of ammonia concentrations.  Data presented will also include longer term passive samplers for ammonia which are used to examine the spatial variability of 2-week average concentrations across northern Colorado in the summer from 2010 to the present.

 

1Colorado State University, kbenedic@engr.colostate.edu
2Department of Atmospheric Science, Colorado State University Fort Collins, CO USA, yixing.shao@colostate.edu
3Department of Atmospheric Science, Colorado State University Fort Collins, CO USA, amy.sullivan@colostate.edu
4Arizona Department of Environmental Quality Phoenix, AZ, lyggd0910@gmail.com
5Department of Atmospheric Science, Colorado State University Fort Collins, CO USA, ejb.bangs@beyondbb.com
6National Park Service/Cooperative Institute for Research in the Atmosphere Fort Collins, CO USA, bret.schichtel@colostate.edu
7Department of Atmospheric Science, Colorado State University Fort Collins, CO USA, jeffrey.collett@colostate.edu