Journal Article
Proceedings of the National Academy of Sciences, vol. 113, iss. 22, pp. 6125-6130, 2016
Authors
Yingjun Liu, Joel Brito, Matthew R. Dorris, Jean C. Rivera-Rios, Roger Seco, Kelvin H. Bates, Paulo Artaxo, Sergio Duvoisin, Frank N. Keutsch, Saewung Kim, Allen H. Goldstein, Alex B. Guenther, Antonio O. Manzi, Rodrigo A. F. Souza, Stephen R. Springston, Thomas B. Watson, Karena A. McKinney, Scot T. Martin
Abstract
Significance
For isolated regions of the planet, organic peroxy radicals produced as intermediates of atmospheric photochemistry have been expected to follow HO
2
rather than NO pathways. Observational evidence, however, has been lacking. An accurate understanding of the relative roles of the two pathways is needed for quantitative predictions of the concentrations of particulate matter, oxidation capacity, and consequent environmental and climate impacts. The results herein, based on measurements, find that the ratio of the reaction rate of isoprene peroxy radicals with HO
2
to that with NO is about unity for background conditions of Amazonia. The implication is that sufficient NO emissions are maintained by natural processes of the forest such that both HO
2
and NO pathways are important, even in this nominally low-NO region.
