Articles | Volume 12, issue 4
Atmos. Chem. Phys., 12, 2077–2098, 2012

Special issue: Quantifying the impact of Boreal fires on tropospheric oxidants...

Atmos. Chem. Phys., 12, 2077–2098, 2012

Research article 21 Feb 2012

Research article | 21 Feb 2012

The influence of boreal biomass burning emissions on the distribution of tropospheric ozone over North America and the North Atlantic during 2010

M. Parrington1, P. I. Palmer1, D. K. Henze2, D. W. Tarasick3, E. J. Hyer4, R. C. Owen5, D. Helmig6, C. Clerbaux7, K. W. Bowman8, M. N. Deeter9, E. M. Barratt1, P.-F. Coheur10, D. Hurtmans10, Z. Jiang11, M. George7, and J. R. Worden8 M. Parrington et al.
  • 1School of GeoSciences, The University of Edinburgh, Edinburgh, UK
  • 2Department of Mechanical Engineering, University of Colorado, Boulder, Colorado, USA
  • 3Air Quality Research Division, Environment Canada, Downsview, Ontario, Canada
  • 4Marine Meteorology Division, Naval Research Laboratory, Monterey, California, USA
  • 5Department of Civil and Environmental Engineering, Michigan Technological University, Houghton, Michigan, USA
  • 6Institute of Arctic and Alpine Research, University of Colorado, Boulder, Colorado, USA
  • 7UPMC Univ. Paris 06; Université Versailles St.-Quentin; CNRS/INSU, LATMOS-IPSL, Paris, France
  • 8Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
  • 9Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, Colorado, USA
  • 10Spectroscopie de l'Atmosphère, Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles (ULB), Brussels, Belgium
  • 11Department of Physics, University of Toronto, Toronto, Ontario, Canada

Abstract. We have analysed the sensitivity of the tropospheric ozone distribution over North America and the North Atlantic to boreal biomass burning emissions during the summer of 2010 using the GEOS-Chem 3-D global tropospheric chemical transport model and observations from in situ and satellite instruments. We show that the model ozone distribution is consistent with observations from the Pico Mountain Observatory in the Azores, ozonesondes across Canada, and the Tropospheric Emission Spectrometer (TES) and Infrared Atmospheric Sounding Instrument (IASI) satellite instruments. Mean biases between the model and observed ozone mixing ratio in the free troposphere were less than 10 ppbv. We used the adjoint of GEOS-Chem to show the model ozone distribution in the free troposphere over Maritime Canada is largely sensitive to NOx emissions from biomass burning sources in Central Canada, lightning sources in the central US, and anthropogenic sources in the eastern US and south-eastern Canada. We also used the adjoint of GEOS-Chem to evaluate the Fire Locating And Monitoring of Burning Emissions (FLAMBE) inventory through assimilation of CO observations from the Measurements Of Pollution In The Troposphere (MOPITT) satellite instrument. The CO inversion showed that, on average, the FLAMBE emissions needed to be reduced to 89% of their original values, with scaling factors ranging from 12% to 102%, to fit the MOPITT observations in the boreal regions. Applying the CO scaling factors to all species emitted from boreal biomass burning sources led to a decrease of the model tropospheric distributions of CO, PAN, and NOx by as much as −20 ppbv, −50 pptv, and −20 pptv respectively. The modification of the biomass burning emission estimates reduced the model ozone distribution by approximately −3 ppbv (−8%) and on average improved the agreement of the model ozone distribution compared to the observations throughout the free troposphere, reducing the mean model bias from 5.5 to 4.0 ppbv for the Pico Mountain Observatory, 3.0 to 0.9 ppbv for ozonesondes, 2.0 to 0.9 ppbv for TES, and 2.8 to 1.4 ppbv for IASI.

Final-revised paper