A second act for the Montreal Protocol

Should anyone need a reminder of just how complex the fight against climate change can be, hydrofluorocarbons will do. They create “a greenhouse effect between hundreds and thousands of times as powerful as carbon dioxide” (although they stay in the atmosphere for less time) and are used in appliances like air conditioners and refrigerators—just the sort of devices more and more in use as temperatures rise.

Ironically they have become more popular because the world rallied three decades ago to do away with chloroflourocarbons, which cause a greenhouse effect as well but were then also depleting the Earth’s ozone layer. That campaign was a success thanks to the 1987 Montreal Protocol, which, according to a recent article in the Economist, “prevented the equivalent of more than 135 billion tonnes of carbon-dioxide emissions, and averted complete collapse of the ozone layer by the middle of the century.” The downside of shedding CFCs, however, has been “a 258 percent increase in the use of heat-trapping HFCs since 1990,” as a New York Times op-ed noted this summer.

Concern over HFC emissions is not new, but now the United States and China, who reached an agreement on the issue three years ago, hope to use the original treaty to galvanize support. As parties to the protocol gather in the capital of Rwanda this weekend, the Economist’s report is a useful guide to how the nations of the world might find a way forward without repeating the unintended consequences of the past.