Emissions of Glyoxal and Other Carbonyl Compounds from Agricultural Biomass Burning Plumes Sampled by Aircraft

Authors

Kyle J. Zarzana, University of Colorado Boulder
Kyung-Eun Min, Gwangju Institute of Science & Technology
Rebecca A. Washenfelder, University of Colorado Boulder
Jennifer Kaiser, Harvard University
Mitchell Krawiec-Thayer, University of Wisconsin - Madison
Jeff Peischl, University of Colorado Boulder
J. Andrew Neuman, University of Colorado Boulder
John B. Nowak, NASA Langley Research Center
Nicholas L. Wagner, University of Colorado Boulder
William P. Dubè, University of Colorado Boulder
Jason M. St. Clair, University of Maryland - Baltimore County
Glenn M. Wolfe, University of Maryland - Baltimore County
Thomas F. Hanisco, NASA Goddard Space Flight Center
Frank N. Keutsch, Harvard University
Thomas B. Ryerson, NOAA Earth System Research Laboratory
Steven S. Brown, NOAA Earth System Research LaboratoryFollow

Date of this Version

2017

Citation

Environ. Sci. Technol. 2017, 51, pp. 11761−11770, DOI: 10.1021/acs.est.7b03517.

Comments

U.S. government work.

Abstract

We report enhancements of glyoxal and methylglyoxal relative to carbon monoxide and formaldehyde in agricultural biomass burning plumes intercepted by the NOAA WP-3D aircraft during the 2013 Southeast Nexus and 2015 Shale Oil and Natural Gas Nexus campaigns. Glyoxal and methylglyoxal were measured using broadband cavity enhanced spectroscopy, which for glyoxal provides a highly selective and sensitive measurement. While enhancement ratios of other species such as methane and formaldehyde were consistent with previous measurements, glyoxal enhancements relative to carbon monoxide averaged 0.0016 ± 0.0009, a factor of 4 lower than values used in global models. Glyoxal enhancements relative to formaldehyde were 30 times lower than previously reported, averaging 0.038 ± 0.02. Several glyoxal loss processes such as photolysis, reactions with hydroxyl radicals, and aerosol uptake were found to be insufficient to explain the lower measured values of glyoxal relative to other biomass burning trace gases, indicating that glyoxal emissions from agricultural biomass burning may be significantly overestimated. Methylglyoxal enhancements were three to six times higher than reported in other recent studies, but spectral interferences from other substituted dicarbyonyls introduce an estimated correction factor of 2 and at least a 25% uncertainty, such that accurate measurements of the enhancements are difficult.