Articles | Volume 16, issue 18
Atmos. Chem. Phys., 16, 11733–11754, 2016
Atmos. Chem. Phys., 16, 11733–11754, 2016
Research article
21 Sep 2016
Research article | 21 Sep 2016

Atmospheric abundance and global emissions of perfluorocarbons CF4, C2F6 and C3F8 since 1800 inferred from ice core, firn, air archive and in situ measurements

Cathy M. Trudinger1, Paul J. Fraser1, David M. Etheridge1, William T. Sturges2, Martin K. Vollmer3, Matt Rigby4, Patricia Martinerie5, Jens Mühle6, David R. Worton7, Paul B. Krummel1, L. Paul Steele1, Benjamin R. Miller8, Johannes Laube2, Francis S. Mani9, Peter J. Rayner10, Christina M. Harth6, Emmanuel Witrant11, Thomas Blunier12, Jakob Schwander13, Simon O'Doherty4, and Mark Battle14 Cathy M. Trudinger et al.
  • 1CSIRO Oceans and Atmosphere, Aspendale, Victoria, Australia
  • 2Centre for Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
  • 3Laboratory for Air Pollution and Environmental Technology, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
  • 4School of Chemistry, University of Bristol, Bristol, UK
  • 5UJF-Grenoble 1/CNRS, Laboratoire de Glaciologie et Géophysique de l'Environnement, 38041 Grenoble, France
  • 6Scripps Institution of Oceanography, University of California at San Diego, La Jolla, California, USA
  • 7National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW, UK
  • 8Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, USA
  • 9School of Biological and Chemical Sciences, University of the South Pacific, Suva, Fiji
  • 10School of Earth Sciences, University of Melbourne, Australia
  • 11UJF-Grenoble 1/CNRS, Grenoble Image Parole Signal Automatique, Grenoble, France
  • 12Center for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
  • 13Climate and Environmental Physics, Physics Institute and Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
  • 14Department of Physics and Astronomy, Bowdoin College, Maine, USA

Abstract. Perfluorocarbons (PFCs) are very potent and long-lived greenhouse gases in the atmosphere, released predominantly during aluminium production and semiconductor manufacture. They have been targeted for emission controls under the United Nations Framework Convention on Climate Change. Here we present the first continuous records of the atmospheric abundance of CF4 (PFC-14), C2F6 (PFC-116) and C3F8 (PFC-218) from 1800 to 2014. The records are derived from high-precision measurements of PFCs in air extracted from polar firn or ice at six sites (DE08, DE08-2, DSSW20K, EDML, NEEM and South Pole) and air archive tanks and atmospheric air sampled from both hemispheres. We take account of the age characteristics of the firn and ice core air samples and demonstrate excellent consistency between the ice core, firn and atmospheric measurements. We present an inversion for global emissions from 1900 to 2014. We also formulate the inversion to directly infer emission factors for PFC emissions due to aluminium production prior to the 1980s. We show that 19th century atmospheric levels, before significant anthropogenic influence, were stable at 34.1 ± 0.3 ppt for CF4 and below detection limits of 0.002 and 0.01 ppt for C2F6 and C3F8, respectively. We find a significant peak in CF4 and C2F6 emissions around 1940, most likely due to the high demand for aluminium during World War II, for example for construction of aircraft, but these emissions were nevertheless much lower than in recent years. The PFC emission factors for aluminium production in the early 20th century were significantly higher than today but have decreased since then due to improvements and better control of the smelting process. Mitigation efforts have led to decreases in emissions from peaks in 1980 (CF4) or early-to-mid-2000s (C2F6 and C3F8) despite the continued increase in global aluminium production; however, these decreases in emissions appear to have recently halted. We see a temporary reduction of around 15 % in CF4 emissions in 2009, presumably associated with the impact of the global financial crisis on aluminium and semiconductor production.

Short summary
Perfluorocarbons (PFCs) are potent, long-lived and mostly man-made greenhouse gases released to the atmosphere mainly during aluminium production and semiconductor manufacture. Here we present the first continuous histories of three PFCs from 1800 to 2014, derived from measurements of these PFCs in the atmosphere and in air bubbles in polar ice. The records show how human actions have affected these important greenhouse gases over the past century.
Final-revised paper