LIMA, Peru — Imagine a looming global catastrophe caused by the spewing of polluting chemicals into the atmosphere.
Now imagine an international treaty approved unanimously in the United Nations that stops the problem dead in its tracks.
Clearly we’re not talking about climate change. But it did happen — when countries came together in the 1980s to tackle the threat from the shrinking ozone layer, the major environmental story of the day. The problem now appears to be on the mend thanks to the 1987 Montreal Protocol.
Despite similarities to the current campaign against climate change, however, differences of scale mean drawing useful lessons is difficult.