I’m referring to the current UN talks in Rwanda to tackle hydrofluorocarbons (HFCs), an extremely potent greenhouse gas found in air conditioners, refrigerators, and foams. These HFCs were originally developed to replace the CFCs that were famously chewing a hole through the ozone layer. But HFCs have since become a major contributor to global warming, so countries are trying to phase them out under the same treaty that got rid of CFCs, the Montreal Protocol.
It won’t be easy to reach an agreement. If the HFC phase-out proves too costly, it could put air conditioning out of reach for millions of people in India and other developing countries who badly need it. But a successful deal would matter greatly for the future of this planet. The stakes are awfully high for such an obscure little meeting. [...]
But we shouldn't forget that we emit other important greenhouse gases, too. There's methane (CH4), which comes from landfills, livestock, and natural gas leaks. There's nitrous oxide (N2O) from agriculture. And there are the halocarbons such as the CFCs and HFCs in our air conditioners and refrigerators that also trap heat when they leak out of aging or faulty equipment and waft into the atmosphere. [...]
So the world's nations got together and enacted the Montreal Protocol in 1989 to phase out CFC use over time. It was one of the all-time great environmental success stories, and the ozone layer is now recovering.
Except for one teensy detail. One of the most popular substitutes for CFCs are a class of chemicals known as HFCs (hydrofluorocarbons). These coolants are fairly harmless to the ozone layer, but they turn out to be extremely potent greenhouse gases — up to 10,000 times as effective at trapping heat as carbon dioxide — when they seep out into the atmosphere.
No comments:
Post a Comment