Newly detected ozone-depleting substances in the atmosphere

Journal name:
Nature Geoscience
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Published online

Ozone-depleting substances emitted through human activities cause large-scale damage to the stratospheric ozone layer, and influence global climate. Consequently, the production of many of these substances has been phased out; prominent examples are the chlorofluorocarbons (CFCs), and their intermediate replacements, the hydrochlorofluorocarbons (HCFCs). So far, seven types of CFC and six types of HCFC have been shown to contribute to stratospheric ozone destruction1, 2. Here, we report the detection and quantification of a further three CFCs and one HCFC. We analysed the composition of unpolluted air samples collected in Tasmania between 1978 and 2012, and extracted from deep firn snow in Greenland in 2008, using gas chromatography with mass spectrometric detection. Using the firn data, we show that all four compounds started to emerge in the atmosphere in the 1960s. Two of the compounds continue to accumulate in the atmosphere. We estimate that, before 2012, emissions of all four compounds combined amounted to more than 74,000 tonnes. This is small compared with peak emissions of other CFCs in the 1980s of more than one million tonnes each year2. However, the reported emissions are clearly contrary to the intentions behind the Montreal Protocol, and raise questions about the sources of these gases.


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  1. Centre for Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich Research Park Norwich NR4 7TJ, UK

    • Johannes C. Laube,
    • Mike J. Newland,
    • Christopher Hogan,
    • Claire E. Reeves &
    • William T. Sturges
  2. Max Planck Institute for Chemistry, Air Chemistry Division, Hahn-Meitner-Weg 1 55128 Mainz, Germany

    • Carl A. M. Brenninkmeijer
  3. Centre for Australian Weather and Climate Research, Commonwealth Scientific and Industrial Research Organisation, Aspendale, Victoria 3195, Australia

    • Paul J. Fraser
  4. CNRS, LGGE, F-38041 Grenoble, France

    • Patricia Martinerie
  5. Univ. Grenoble Alpes, LGGE, F-38041 Grenoble, France

    • Patricia Martinerie
  6. National Centre for Atmospheric Science, School of Environmental Sciences, University of East Anglia, Norwich Research Park Norwich NR4 7TJ, UK

    • David E. Oram
  7. Institute for Marine and Atmospheric Research, Utrecht University, Princetonplein 5 3584 CC Utrecht, The Netherlands

    • Thomas Röckmann
  8. Physics Institute, University of Berne, Sidlerstrasse 5 CH-3012 Bern, Switzerland

    • Jakob Schwander
  9. UJF—Grenoble1 / CNRS, Grenoble Image Parole Signal Automatique (GIPSA-lab), UMR 5216, B.P. 46 F-38402 St Martin d’Hères, France

    • Emmanuel Witrant
  10. Present address: School of Geography, College of Life and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK.

    • Mike J. Newland


J.C.L. and C.H. performed the measurements, M.J.N. and C.E.R. modelled the emissions and P.M. and E.W. the firn air data. C.A.M.B., P.J.F., D.E.O., T.R. and J.S. collected and provided air samples and all authors contributed to the interpretation and the writing of the manuscript.

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The authors declare no competing financial interests.

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