10th International Aerosol Conference
September 2 - September 7, 2018
America's Center Convention Complex
St. Louis, Missouri, USA

Abstract View


Impact of Ammonium Nitrate Aerosol Formation on Ozone Production in Urban and Rural New York State

MATTHEW NINNEMAN, Sarah Lu, Pius Lee, Jeffery McQueen, James Schwab, University at Albany, SUNY

     Abstract Number: 513
     Working Group: Aerosol Chemistry

Abstract
The nighttime deposition of ammonium nitrate aerosol (NH4NO3) onto surfaces is an important oxides of nitrogen (NOx) removal pathway, which affects next-day photochemical ozone (O3) production. Prior studies have mainly examined this phenomenon in either urban or rural environments. However, these studies have not compared the impact of NH4NO3 formation on O3 production in urban versus rural locations. To address this research gap, this study used continuous NH4NO3, ammonia (NH3), nitric acid (HNO3), NOx, and O3 measurements taken in one urban location and one rural location in New York State (NYS) beginning in mid-2016. In addition, photochemical ozone production rates (PO3) and concentrations of dinitrogen pentoxide (N2O5), water vapor (H2O), nitrous acid (HONO) and gas-phase nitrate (NO3) are determined for both sites using an air quality model. The urban and rural locations of interest were Queens College (QC) in Flushing, New York (NY), and Pinnacle State Park (PSP) in Addison, NY, respectively. The effect of NH4NO3 formation and deposition on next-day photochemical O3 production differs at QC and PSP. This may be due in part to (1) differences in modeled N2O5 and NO3 concentrations and measured NH3, HNO3, and NOx concentrations, (2) differences in NOx-sensitive versus NOx-saturated environments, and (3) differences in the extent of poorly characterized NOx sources from surface-enhanced re-noxification, all of which are explored in this study.