The Montreal Protocol was created by some 200 nations to deal with the effect of chlorofluorocarbons (CFCs) on the ozone hole. It seems to be working. CFC use has virtually ended and the ozone hole has finally started to heal.
Where does the Law of Unintended Consequences come in? When CFCs were invented, it was thought they were inert. Years later it was discovered that when a CFC molecule got high enough in the atmosphere, ultraviolet light from the sun would knock off a chlorine molecule which would then react with ozone, and break it down. Hence, CFCs got blamed for the growth of the Antarctic ozone hole.
Since the Montreal protocol was implemented, virtually all CFCs have been replaced with a family of hydrofluorocarbons (HFCs). HFCs were thought to be safe until someone noticed that HFCs have a huge and unintended consequence: they are extremely potent greenhouse gasses (GHG).
HFCs are 100-3000 times more potent than CO2. The most abundant HFC, HFC-134a, is 1,300 times more potent than CO2.
Today, the small amount of HFCs in the atmosphere keeps them from playing a large role in global warming. However, HFCs are very stable; what is already in the atmosphere may be there for hundreds of years. HFC-134a, for example, has a lifetime of about 13 years in the atmosphere. That’s not as long as CO2, which can last for tens of thousands of years.
HFCs are created and released more and more often as they are manufactured, as air conditioning units leak or are scrapped without the gas being recovered.
This week, representatives of nearly 200 members of the Montreal Protocol met in Kigali, Rwanda to address HFCs.
There is little about the conference in the US mainstream media. Google searches (and I’m a fair dinkum searcher) showed pre-conference coverage only by Voice of America, Reuters, Vox, Physics.org, the Daily Mail, and Reuters UK.
“The Washington Post” ran in July a preview of an earlier conference in Vienna.
CNN posted a summary of the Rwanda agreement on Saturday, 15 October 2016, within minutes of the Kigali agreement being reached.
A search for comments by Presidential Candidates yielded zero hits for Clinton, and from Trump, only an old diatribe on hairspray, which contained several factual errors.
By passing the Kigali Amendment to the Montreal Protocol, member nations agreed to reduce HFCs. The reduction is expected to protect the environment from what was predicted to be a 0.5 degree Centigrade rise in overall global temperature. That’s just shy of one degree Fahrenheit.
But what will replace HFCs, and will we see more unintended consequences?
At present, the candidates include carbon dioxide and ammonia, and a family of chemicals composed of hydrogen, fluorine, and carbon, called hydrofloroolefins (HFOs). They are short-lived if released into the atmosphere. One known unintended consequence is that one member of the family breaks down to trifluoracetic acid (TFA), which is then washed out by precipitation. The ultimate effect is not known, but it is judged to be negligible compared to natural sources of TFA.
Let’s keep our guard up (and our fingers crossed).
All references were accessed on 2016-10-15
Registered Curmudgeon, scientist, skeptic, humanist, and writer.