Enhancements in Inorganic Aerosol Production in New York City and Downwind: Connecting In-Situ Oxidation Experiments with ASCENT Field Observations to Examine Key Chemical and Environmental Factors
TORI HASS-MITCHELL, Andrew Lambe, Mitchell Rogers, Taekyu Joo, Catelynn Soong, Jordan Krechmer, Benjamin A. Nault, Drew Gentner, Yale University
Abstract Number: 494
Working Group: Coast to Coast Campaigns on Aerosols, Clouds, Chemistry, and Air Quality
Abstract
Despite representing only ~20% of PM2.5 in U.S. urban areas with declining concentrations, inorganic aerosols have a significant influence on aerosol physicochemical properties. Episodic enhancements in secondary inorganic aerosols were observed following exposure to hydroxyl (OH) radicals in an oxidation flow reactor (OFR) coupled to an aerosol chemical speciation monitor (ACSM) at a receptor site in northern Manhattan, NYC during the summer 2022 NYC-METS (New York City metropolitan Measurements of Emissions and TransformationS) intensive. During the same period, relatively consistent minor enhancements in secondary organic aerosols were also observed. These results were compared to long-term baseline ACSM measurements at the ASCENT (Atmospheric Science and Chemistry mEasurement NeTwork) network site in Queens, NYC. Environmental and meteorological factors, including relative humidity and its impacts on aerosol liquid water, as well as reactive precursor concentrations, were found to be key factors influencing the episodic inorganic enhancements across all seasons. These results highlight the significance of NOx and SO2 emissions in the NYC region and inform the importance of continued attention to inorganic species in research and PM2.5 control policies in NYC, downwind areas, and other similar regions.