A41K-0227
Examining the Role of N2O5 Hydrolysis and ClNO2 Production Over the Northeast United States: Results from WINTER 2015 Aircraft Campaign
Thursday, 17 December 2015
Poster Hall (Moscone South)
Jessica Haskins1, Lyatt Jaegle2, Joel A Thornton3, Viral Shah4, Felipe Lopez-Hilfiker4, Ben H. Lee4, Dorothy L Fibiger5, Erin McDuffie6, Steven S Brown6, Jose L Jimenez7, Rodney J Weber8, Jack E Dibb9, Douglas A Day10, John S Holloway11, Marc Nicholas Fiddler12, Pedro Campuzano Jost13, Jason Clay Schroder14, Amy Sullivan15, Patrick R Veres6 and Jaime Ross Green12, (1)University of Washington Seattle Campus, Atmospheric Sciences, Seattle, WA, United States, (2)Univ Washington, Seattle, WA, United States, (3)Univ Washington - Seattle, Seattle, WA, United States, (4)University of Washington Seattle Campus, Seattle, WA, United States, (5)National Science Foundation, Atmospheric and Geospace Sciences Postdoctoral Fellow, Arlington, VA, United States, (6)NOAA Boulder, Boulder, CO, United States, (7)University of Colorado at Boulder, Dept. of Chemistry and Biochemistry, Boulder, CO, United States, (8)Georgia Institute of Technology Main Campus, Atlanta, GA, United States, (9)University of New Hampshire Main Campus, Durham, NH, United States, (10)CIRES, Boulder, CO, United States, (11)Aerodyne Research Inc., Billerica, MA, United States, (12)North Carolina A & T State University, Physics, Greensboro, NC, United States, (13)University of Colorado Boulder, Boulder, CO, United States, (14)Cooperative Institute for Research in Environmental Sciences, Boulder, CO, United States, (15)Colorado State University, Fort Collins, CO, United States
Abstract:
The heterogeneous uptake of N2O5 on liquid aerosol particles plays a critical role in regulating tropospheric reactive nitrogen (NOx) availability, particle nitrate loadings, and halogen activity, which, in turn, have downwind effects on oxidant availability and ozone production. However, parameterizations of this process in regional and global models remain relatively untested. Measurements taken during the 2015 Wintertime Investigation of Transportation, Emissions, & Reactivity (WINTER) allow both empirical and theoretical calculations of the N2O5 reactive uptake coefficient (γ) and ClNO2 yield (Y) during 13 winter flights over the eastern US. We use observations of gas and particle composition as inputs to the offline thermodynamic equilibrium models, ISORROPIA II and AIM, to generate outputs of particulate aqueous phase concentrations of NO3-(aq), Cl-(aq), and H2O(l) . These outputs are used to theoretically calculate γ (N2O5) and Y(ClNO2), using the parameterizations described in Bertram & Thornton, 2009. The calculated values are then compared to the empirical counterparts to assess the validity of the parameterization’s representation of temperature, humidity, and composition dependences. The updated parameterization is then used in the online GEOS-Chem chemical transport model to examine the role of wintertime multiphase chemistry in controlling the regional distribution and export of NOx and Cl-atom source downwind of the northeast United States.