Hydrofluorocarbons or HFCs were introduced to save the ozone layer in the upper atmosphere from destruction. When the world agreed in 1987 to phase out chlorofluorocarbons (CFCs) through the Montreal Protocol, the chemical industry came up with HFCs as a replacement in applications such as refrigeration, air conditioning and making insulating foams.
While HFCs do not initiate ozone-destroying chemical reactions in the upper atmosphere, like CFCs, they turn out to be extremely powerful greenhouse gases – and now the environmental movement is rightly alarmed that growing use of HFCs could seriously exacerbate global warming.
Individual HFC molecules have a greenhouse effect many hundreds of times greater than carbon dioxide. At present they are present in the atmosphere only in small traces, so their total contribution to global warming is less than 1 per cent that of carbon dioxide.
But projections for the future see a huge increase in HFC use over the next few years, mainly for refrigeration and air conditioning in the developing world. A recent study by scientists at the US National Oceanic and Atmospheric Administration (NOAA) showed that, without restrictions, annual HFC emissions could heat the atmosphere by as much as 8bn tonnes of carbon dioxide by 2050.
So pressure is building for HFCs to be phased out too. The Environmental Investigation Agency (EIA), a green NGO, is leading a campaign for them to be banned under the Montreal Protocol, whose member countries are meeting in Geneva later this week.
The move has support from Achim Steiner, executive director of the UN Environment Programme, who said: “Action to freeze and then reduce this group of gases could buy the world the equivalent of a decade’s worth of carbon dioxide emissions.”
Campaigners point out that it may be easier to use the existing machinery of the Montreal Protocol, which regulates chemicals very similar to HFCs, than to try to include HFCs in climate change treaties which concentrate on carbon dioxide.