It was an environmental and political success story that resonates in today’s contentious debates over climate change. In the 1980s, the planet was threatened by the growth of a continent-sized hole in the ozone layer above Antarctica, a hole that scientists determined was due to the impact of human-made chemicals called chlorofluorocarbons, or CFCs, found in refrigerants and hairsprays. The ozone layer provides vital protection from the sun’s high-frequency ultraviolet rays. The alarming erosion of that layer provoked international concern and, eventually, the Montreal Protocol that led to…