Plume Evolution and NOx Lifetime in the Denver Metropolitan Area
Abstract
NOx (NOx≡NO+NO2) is abundant in urban areas due to its emission via combustion processes. As NOx is transported away from cities, it undergoes photochemical oxidation to produce a variety of nitrogen oxide products, including peroxynitrates (PNs), alkyl nitrates (ANs), and nitric acid (HNO3). These species have different loss mechanisms and lifetimes, meaning that ongoing nitrogen oxide chemistry may differ greatly in the near- and far-field of cities. Understanding the evolution of NOx and NOy (NOy≡NOx+PNs+ANs+HNO3+…) - including the relative balance between NOx oxidation products and their overall concentrations - as air masses are transported away from cities is imperative to constraining the lifetime of NOx and understanding how air quality regulations aimed at lowering NOx emissions might impact air quality in the near- and far-field of urban areas. We have used observations from the Front Range Air Pollution and Photochemistry Experiment (FRAPPÉ) to investigate the evolution of NOx in air masses originating from the Denver urban area, and our results are contrasted with examples from other cities.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.A42A..07E
- Keywords:
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- 0317 Chemical kinetic and photochemical properties;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0365 Troposphere: composition and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0368 Troposphere: constituent transport and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 3305 Climate change and variability;
- ATMOSPHERIC PROCESSES