Satellite boreal measurements over Alaska and Canada during June–July 2004: Simultaneous measurements of upper tropospheric CO, C₂H₆, HCN, CH₃Cl, CH₄, C₂H₂, CH₃OH, HCOOH, OCS, and SF₆ mixing ratios

Simultaneous ACE (Atmospheric Chemistry Experiment) upper tropospheric CO, C 2 H 6 , HCN, CH 3 Cl, CH 4 , C 2 H 2 , CH 3 OH, HCOOH, and OCS measurements show plumes up to 185 ppbv (10 −9 per unit volume) for CO, 1.36 ppbv for C 2 H 6 , 755 pptv (10 −12 per unit volume) for HCN, 1.12 ppbv for CH 3 Cl, 1.82 ppmv (10 −6 per unit volume) for CH 4 , 0.178 ppbv for C 2 H 2 , 3.89 ppbv for CH 3 OH, 0.843 ppbv for HCOOH, and 0.48 ppbv for OCS in western Canada and Alaska at 50°N–68°N latitude between 29 June and 23 July 2004. Enhancement ratios and emission factors for HCOOH, CH 3 OH, HCN, C 2 H 6 , and OCS relative to CO at 250–350 hPa are inferred from measurements of young plumes compared with lower mixing ratios assumed to represent background conditions based on a CO emission factor derived from boreal measurements. Results are generally consistent with the limited data reported for various vegetative types and emission phases measured in extratropical forests including boreal forests. The low correlation between fire product emission mixing ratios and the SF 6 mixing ratio is consistent with no significant SF 6 emissions from the biomass fires.