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Environmental contextChlorofluorocarbons (CFCs) are potent greenhouse and stratospheric ozone depleting trace gases. Their atmospheric concentrations are in decline, thanks to global production and consumption controls imposed by the Montreal Protocol. In recent years, the rates of decline of CFC atmospheric concentrations, especially for CFC-11 (CCl3F), are not as large as anticipated under the Protocol, resulting in renewed efforts to estimate CFC consumption and/or emissions to possibly identify new or poorly quantified sources. AbstractAustralian emissions of chlorofluorocarbons (CFCs) have been estimated from atmospheric CFC observations by both inverse modelling and interspecies correlation techniques, and from CFC production, import and consumption data compiled by industry and government. Australian and global CFC emissions show similar temporal behaviour, with emissions peaking in the late-1980s and then declining by ~10% per year through to the present. Australian CFC emissions since 1978 account for less than 1% of global emissions and therefore make a correspondingly small contribution to stratospheric ozone depletion. The current CFC emissions in Australia are likely from ‘banks’ of closed-cell foams, and refrigeration–air conditioning equipment now more than 20 years old. There is no evidence of renewed consumption or emissions of CFCs in Australia. The reduction in CFC emissions has made a significant contribution to reducing Australian greenhouse gas emissions.

International efforts to limit global warming and ocean acidification aim to slow the growth of atmospheric CO2, guided primarily by national and industry estimates of production and consumption of fossil fuels. Atmospheric verification of emissions is vital but present global inversion methods are inadequate for this purpose. We demonstrate a clear response in atmospheric CO2coinciding with a sharp 2010 increase in Asian emissions but show persisting slowing mean CO2growth from 2002/03. Growth and inter-hemispheric concentration difference during the onset and recovery of the Global Financial Crisis support a previous speculation that the reported 2000–2008 emissions surge is an artefact, most simply explained by a cumulative underestimation (∼ 9 Pg C) of 1994–2007 emissions; in this case, post-2000 emissions would track mid-range of Intergovernmental Panel on Climate Change emission scenarios. An alternative explanation requires changes in the northern terrestrial land sink that offset anthropogenic emission changes. We suggest atmospheric methods to help resolve this ambiguity.