Ozone Production Efficiencies at Rural New York State Locations: Relationship to Oxides of Nitrogen Concentrations

Abstract

This study examined the observed summertime ozone production efficiency (OPE) and background ozone ([O3]) concentration at two rural sites in New York State, Pinnacle State Park (PSP) in Addison, NY, and Whiteface Mountain Summit (WFMS) in Wilmington, NY. Observed summertime OPEs and their relationship to oxides of nitrogen concentrations ([NOx]) were assessed during photochemically active periods at PSP and WFMS from 2000 to 2017 and 2015–2017, respectively. The summertime OPE increased in response to [NOx] reductions at PSP, consistent with a NOx‐sensitive regime for O3 production. At PSP, the summertime OPE increased from approximately 5–7 parts per billion per parts per billion (ppb ppb−1) in 2000–2009 to approximately 13 ppb ppb−1 in 2012–2017, and the median [NOx] concentration during photochemically productive periods decreased from about 0.60 ppb in 2000–2005 to about 0.23 ppb in 2012–2017. At WFMS, the summertime OPE was approximately 18 ppb ppb−1 in 2015–2017, and the median [NOx] concentration during photochemically active periods from 2015 to 2017 was about 0.21 ppb. The higher WFMS summertime OPE is consistent for a site characterized by lower [NOx] concentrations. The summertime background [O3] concentration at PSP and WFMS was approximately 31–33 ppb for the analysis period, indicating that both sites were likely affected by similar regional emission sources.

Vertical Profiles of Ozone Concentrations in the Lower Troposphere Downwind of New York City During LISTOS 2018–2019

“…Excluding situations of chemical titration (mainly caused by high NO concentrations), strong spatial variability in ozone typically indicates very local influences on circulation such that pollution transport cannot be well described by Gaussian diffusion in a stably advecting air mass. Even though reactant concentrations decrease, ozone production efficiency increases as a result of the lower NO x , so overall ozone production may increase and/or remain strong for tens or hundreds of kilometers downwind (Godowitch et al., 2008; Liu et al., 1987; Ninneman et al., 2019; Zaveri et al., 2003). For this reason, sites downwind of strong urban emissions may experience higher ozone levels than the urban locations where the precursor pollutants originated.…”

Mobile Laboratory Measurements of High Surface Ozone Levels and Spatial Heterogeneity During LISTOS 2018: Evidence for Sea Breeze Influence

“…Ground‐level ozone (O 3 ) is a regional pollutant with an 8‐hr standard of 70 parts per billion (ppb), as mandated by the U.S. Environmental Protection Agency (US EPA, 2017). O 3 is mainly formed due to photochemical reactions involving nitrogen oxides (NO x ) and volatile organic compounds (VOCs; National Research Council, 1991; Gaudel et al, 2018; Ninneman et al, 2019). High ground‐level O 3 concentrations contribute to photochemical smog and negative human health and ecosystem impacts (Karnosky et al, 2007; Martins et al, 2012).…”

Sensitivity of Tropospheric Ozone Over the Southeast USA to Dry Deposition

“…We have shown that two metrics for OPE, a concentration‐based metric that is frequently applied to observations (e.g., Blanchard et al, 2014; Ninneman et al, 2019; Sillman et al, 1998; Trainer et al, 1993) and the modeled ratio of ozone production to NO x loss, differ in the sign and magnitude of response when ozone or NO y DD is shut off. We conclude that changes in DD could confound attribution of changes in the OPE to NO x emission trends inferred from measured concentrations.…”