Recent trends in global emissions of HCFCs and HFCs

Global-scale atmospheric measurements were used by S.A. Montzka et al. to investigate the effectiveness of recent adjustments to production and consumption controls on HCFCs under the Montreal Protocol.
Global-scale atmospheric measurements were used by S.A. Montzka et al.* to investigate the effectiveness of recent adjustments to production and consumption controls on HCFCs under the Montreal Protocol, and to assess recent projections of large increases in HFC production and emission.

The results show that aggregate global HCFC emissions did not increase appreciably during 2007–2012 and suggest that the 2007 Adjustments to the Montreal Protocol played a role in limiting HCFC emissions well in advance of the 2013 cap on global production. HCFC emissions varied between 0.76 and 0.79 GtCO2-eq/y during this period.

Despite slower than projected increases in aggregate HCFC emissions since 2007, total emissions of HFCs used as substitutes for HCFCs and CFCs increased by 45% during 2007–2012 and by 2012 had reached 0.51 (-0.03, +0.04) GtCO2-eq/y, a magnitude approximately double the emissions reported to the United Nations Framework Convention on Climate Change (UNFCCC) for these HFCs.

 Assuming accurate reporting to the UNFCCC, the results imply that developing countries (non-Annex I Parties) not reporting to the UNFCCC now account for nearly 50% of global HFC emissions used as substitutes for ozone-depleting substances.

The authors also estimate that applications responsible for HFC emissions in 2012 can be divided into three equally contributing categories: mobile air conditioning, commercial refrigeration, and the sum of all other activities. Efforts to adopt lower GWP alternatives, particularly for MAC and commercial refrigeration, have the potential to facilitate significant reductions in CO2-eq emissions of HFCs.

* S.A. Montzka et al. Recent Trends in Global Emissions of Hydrochlorofluorocarbons and Hydrofluorocarbons: Reflecting on the 2007 Adjustments to the Montreal Protocol, The Journal of Physical Chemistry, Nov. 2014