Factors influencing atmospheric composition over subarctic North America during summer
Article first published online: 21 SEP 2012
Copyright 1994 by the American Geophysical Union.
Journal of Geophysical Research: Atmospheres (1984–2012)
Volume 99, Issue D1, pages 1887–1897, 20 January 1994
How to Cite
1994), Factors influencing atmospheric composition over subarctic North America during summer, J. Geophys. Res., 99(D1), 1887–1897, doi:10.1029/93JD02256., , , , , , , and (
- Issue published online: 21 SEP 2012
- Article first published online: 21 SEP 2012
- Manuscript Accepted: 6 AUG 1993
- Manuscript Received: 12 APR 1993
Elevated concentrations of hydrocarbons, CO, and nitrogen oxides were observed in extensive haze layers over northeastern Canada in the summer of 1990, during ABLE 3B. Halocarbon concentrations remained near background in most layers, indicating a source from biomass wildfires. Elevated concentrations of C2Cl4 provided a sensitive indicator for pollution from urban/industrial sources. Detailed analysis of regional budgets for CO and hydrocarbons indicates that biomass fires accounted for ≈ 70% of the input to the subarctic for most hydrocarbons and for acetone and more than 50% for CO. Regional sources for many species (including CO) exceeded chemical sinks during summer, and the boreal region provided a net source to midlatitudes. Interannual variations and long-term trends in atmospheric composition are sensitive to climatic change; a shift to warmer, drier conditions could increase the areas burned and thus the sources of many trace gases.