Articles | Volume 13, issue 15
Atmos. Chem. Phys., 13, 7567–7585, 2013

Special issue: Firn air: archive of the recent atmosphere

Atmos. Chem. Phys., 13, 7567–7585, 2013

Research article 06 Aug 2013

Research article | 06 Aug 2013

A 60 yr record of atmospheric carbon monoxide reconstructed from Greenland firn air

V. V. Petrenko1,2, P. Martinerie3, P. Novelli4, D. M. Etheridge5, I. Levin6, Z. Wang7, T. Blunier8, J. Chappellaz3, J. Kaiser9, P. Lang4, L. P. Steele5, S. Hammer6, J. Mak7, R. L. Langenfelds5, J. Schwander10, J. P. Severinghaus11, E. Witrant12, G. Petron4, M. O. Battle13, G. Forster9, W. T. Sturges9, J.-F. Lamarque14, K. Steffen15,16, and J. W. C. White1,17 V. V. Petrenko et al.
  • 1Institute of Arctic and Alpine Research (INSTAAR), University of Colorado, Boulder, CO 80309, USA
  • 2Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627, USA
  • 3UJF – Grenoble 1/CNRS, Laboratoire de Glaciologie et Géophysique de l'Environnement (LGGE) UMR5183, Grenoble, 38041, France
  • 4NOAA ESRL Global Monitoring Division, Boulder, CO 80305, USA
  • 5Centre for Australian Weather and Climate Research, CSIRO Marine and Atmospheric Research, Aspendale, Victoria 3195, Australia
  • 6Institut für Umweltphysik, Heidelberg University, 69120 Heidelberg, Germany
  • 7School of Marine and Atmospheric Sciences/Institute for Terrestrial and Planetary Atmospheres, State University of New York at Stony Brook, Stony Brook, NY 11794, USA
  • 8Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, 2100 København Ø, Denmark
  • 9School of Environmental Sciences, University of East Anglia (UEA), Norwich NR4 7TJ, UK
  • 10University of Berne, Physics Institute, 3012 Bern, Switzerland
  • 11Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, USA
  • 12UJF – Grenoble 1/CNRS, Grenoble Image Parole Signal Automatique (GIPSA-lab), UMR5216, B.P. 46, 38402 St Martin d'Hères, France
  • 13Department of Physics and Astronomy, Bowdoin College, 8800 College Station, Brunswick, ME 04011, USA
  • 14National Center for Atmospheric Research, Boulder, CO 80301, USA
  • 15Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, USA
  • 16Swiss Federal Research Institute WSL, 8903 Birmensdorf, Switzerland
  • 17Geological Sciences and Environmental Studies, University of Colorado, Boulder, CO 80309, USA

Abstract. We present the first reconstruction of the Northern Hemisphere (NH) high latitude atmospheric carbon monoxide (CO) mole fraction from Greenland firn air. Firn air samples were collected at three deep ice core sites in Greenland (NGRIP in 2001, Summit in 2006 and NEEM in 2008). CO records from the three sites agree well with each other as well as with recent atmospheric measurements, indicating that CO is well preserved in the firn at these sites. CO atmospheric history was reconstructed back to the year 1950 from the measurements using a combination of two forward models of gas transport in firn and an inverse model. The reconstructed history suggests that Arctic CO in 1950 was 140–150 nmol mol−1, which is higher than today's values. CO mole fractions rose by 10–15 nmol mol−1 from 1950 to the 1970s and peaked in the 1970s or early 1980s, followed by a ≈ 30 nmol mol−1 decline to today's levels. We compare the CO history with the atmospheric histories of methane, light hydrocarbons, molecular hydrogen, CO stable isotopes and hydroxyl radicals (OH), as well as with published CO emission inventories and results of a historical run from a chemistry-transport model. We find that the reconstructed Greenland CO history cannot be reconciled with available emission inventories unless unrealistically large changes in OH are assumed. We argue that the available CO emission inventories strongly underestimate historical NH emissions, and fail to capture the emission decline starting in the late 1970s, which was most likely due to reduced emissions from road transportation in North America and Europe.

Final-revised paper