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

Abstract

Simultaneous ACE (Atmospheric Chemistry Experiment) upper tropospheric CO, C2H6, HCN, CH3Cl, CH4, C2H2, CH3OH, HCOOH, and OCS measurements show plumes up to 185 ppbv (10−9 per unit volume) for CO, 1.36 ppbv for C2H6, 755 pptv (10−12 per unit volume) for HCN, 1.12 ppbv for CH3Cl, 1.82 ppmv (10−6 per unit volume) for CH4, 0.178 ppbv for C2H2, 3.89 ppbv for CH3OH, 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, CH3OH, HCN, C2H6, 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 SF6 mixing ratio is consistent with no significant SF6 emissions from the biomass fires.

ACE-FTS measurements of trace species in the characterization of biomass burning plumes

“…The only exceptions is for the emission factors of HCN associated with Boreal fires, where our values are an order of magnitude smaller than those reported by Akagi et al (2011); although when compared to the emission factor obtained by Rinsland et al (2007), our values confirm the emission factors of HCN previously obtained using ACE-FTS. Rinsland et al (2007) also made note of this same discrepancy when comparing their emission factors to the results obtained from the airborne measurements conducted by Yokelson et al (1997).…”

“…The only exceptions is for the emission factors of HCN associated with Boreal fires, where our values are an order of magnitude smaller than those reported by Akagi et al (2011); although when compared to the emission factor obtained by Rinsland et al (2007), our values confirm the emission factors of HCN previously obtained using ACE-FTS. Rinsland et al (2007) also made note of this same discrepancy when comparing their emission factors to the results obtained from the airborne measurements conducted by Yokelson et al (1997). Given the small number of ACE-FTS measurements used and that emission factors are being calculated using enhancement factors from plumes 2-3 days old and not from fresh biomass burning emissions from which the emission factors provide by Akagi et al (2011) are derived, the discrepancy here is not totally unexpected.…”

“…Finally, SF 6 was also included in the study. Although it was demonstrated by Rinsland et al (2007) that SF 6 does not correlate with the VMRs of species emitted from fires and that the SF 6 mixing ratio is consistent with no significant SF 6 emissions from biomass burning, we treat SF 6 in this work as a reference species to identify any potentially anomalous results in our calculations.…”

Global distributions of methanol and formic acid retrieved for the first time from the IASI/MetOp thermal infrared sounder

“…Methanol and formic acid, along with a series of other compounds, have been observed in young or aged biomass burning plumes with the ACE-FTS instrument Dufour et al, 2006;Coheur et al, 2007;Rinsland et al, 2007;Herbin et al, 2009). Large datasets of that sounder, covering several years, have been gathered to provide quasiglobal distributions of these two species and to study their seasonal variability Published by Copernicus Publications on behalf of the European Geosciences Union.…”

Determination of enhancement ratios of HCOOH relative to CO in biomass burning plumes by the Infrared Atmospheric Sounding Interferometer (IASI)

“…There has been a recent interest in calculating enhancement ratios and emission factors from satellite data (e.g., Rinsland et al, 2007;Coheur et al, 2009;Tereszchuk et al, 2011). The above difficulty of inferring emission factors using the satellite observations comes from the fact that these observations are indeed typically made in the free-upper troposphere and further downwind of the fires.…”