While carbon dioxide is certainly a major culprit in relation to climate change, many other gases play a role as well – and some are posing a serious threat.
 
Back in 1989, chlorofluorocarbons (CFCs) were rapidly phased out under the Montreal Protocol on Substances That Deplete the Ozone Layer. Up until that point, CFCs were commonly used in refrigerant, propellant, medicinal and degreasing applications.
 
Aside from damaging the ozone layer, CFCs are also powerful heat trapping gases.

Hydrochlorofluorocarbons (HCFC) are also currently being phased out for the same reasons. As mentioned in my article on other greenhouse gases; HCFCs have many times the Global Warming Potential (GWP) of carbon dioxide – up to 1600 times.

The chemicals that have replaced both CFC and HCFC gases are mostly the non-ozone destroying HFC compounds – hydrofluorocarbons. 

There are certainly far more air conditioners and refrigerators around now than there were 20 years ago and while the ozone layer may be recovering, HFC’s are making a considerable contribution to the biggest current environmental threat we face  – climate change. 

A recent report from the United Nations Environment Program has sounded the alarm about HFCs; stating that by 2050 these compounds could be responsible for emissions equivalent to 3.5 to 8.8 Gigatonnes (Gt) of carbon dioxide.

The UN says HFC usage is rising and one of the most widely used forms, HFC 134a, has increased in the atmosphere by about 10 per cent per year just since 2006.

HFC-134a has an atmospheric lifetime of 14 years and a Global Warming Potential of around 1,300 times that of carbon dioxide.

So what do we do now? 

The UN recommends designing more energy efficient buildings to decrease the need for air-conditioning and the use of substitutes such as ammonia and dimethyl ether; along with wider use of shorter-lived HFCs such as HFC-1234ze, which has an atmospheric life of months rather than years.

Based on the HCFC/CFC to HFC experience, I wonder if by swapping to these other substances if we may just see new environmental threats biting us on the butt in a few decades from now.

Learn more about other greenhouse gases.