Composition and Chemistry
On alkyl nitrates, O3, and the “missing NOy”
Article first published online: 20 AUG 2003
Copyright 2003 by the American Geophysical Union.
Journal of Geophysical Research: Atmospheres (1984–2012)
Volume 108, Issue D16, 27 August 2003
How to Cite
2003), On alkyl nitrates, O3, and the “missing NOy”, J. Geophys. Res., 108, 4501, doi:10.1029/2003JD003685, D16., , , , , , and (
- Issue published online: 20 AUG 2003
- Article first published online: 20 AUG 2003
- Manuscript Accepted: 19 JUN 2003
- Manuscript Revised: 11 JUN 2003
- Manuscript Received: 14 APR 2003
- alkyl nitrates;
 We describe measurements of NO2, total peroxy nitrates (ΣPNs), total alkyl nitrates (ΣANs), and HNO3 using thermal dissociation followed by laser-induced fluorescence detection of NO2 at three continental locations. The ΣAN observations are unique and provide novel constraints on atmospheric photochemistry. At a rural site in California, measurements over a full annual cycle show that ΣANs are routinely 10–20% of NOy. At this rural site, at a suburban site in California and an urban site in Houston, Texas, both the absolute concentration of ΣANs and the fraction of the higher oxides of nitrogen (NOz) represented by ΣANs are greater than or equal to values reported in any prior observations. Although the contrast with prior observations is striking, we show that large abundances of ΣANs are consistent with simple chemical models of tropospheric ozone production and with the few prior comprehensive model studies. We also show that ΣANs are a large part, if not all, of the “missing NOy” reported in many prior experiments and emphasize that the ratios of ΣANs/NOz and of O3/ΣANs are especially useful for evaluating chemical models and comparing observations at different sites.