Ozone productivity of atmospheric organics

Abstract

A technique is developed to determine the amount of ozone and other products, such as nitric acid and peroxyacetylnitrate (PAN), generated by the individual organic components of a complex atmospheric organic/NOx mixture. The technique is applied to the SAPRC 90 photochemical mechanism to study the individual contributions of carbonyls, aromatics, alkanes, alkenes, and carbon monoxide to ozone, nitric acid, PAN, and free radical production at varying organic to NOx ratios typical of atmospheric conditions.

Marginal PM25: Nonlinear Aerosol Mass Response to Sulfate Reductions in the Eastern United States

“…Such reductions in emissions of NO x and organics would have the added benefits of concurrently addressing proposed NAAQS for tropospheric ozone. 32,33 Thus, the NO x emissions reductions proposed for the eastern United States to address the ozone standards may also be an important component of a strategy to reduce PM 2.5 .…”

Reactivity Scales as Comparative Tools for Chemical Mechanisms

“…1 Organic compounds in such an atmosphere, even with sufficient NO x , may be classed as unreactive if they react slowly and if changes in their emissions have limited effects on ozone episodes. Some organic compounds form ozone more quickly or may degrade through reaction pathways that produce more ozone.…”

An Alternative Approach to Photochemical Ozone Creation Potentials Applied under European Conditions

“…This leaves a lower percentage of RO 2 for reactions leading to O 3 production and, hence, the amount of O 3 produced per emitted VOC decreases. 13,37,38 VOCs are important for O 3 production in low-NO x regime areas as well, where O 3 formation is mainly governed by the availability of NO x . The ability to produce O 3 varies between different VOCs even under these conditions.…”

“…The very same VOC may produce more O 3 under conditions with higher NO x concentrations. 13,37,38 The maximum changes in O 3 concentration caused by VOC emissions will take place on different time scales depending on the reactivity of the VOC. For a highly reactive species, all the VOC emitted from the local source will react quickly and lead to a maximum concentration on the same day as the emission occurs.…”