This Day in History: 1987-09-16

Montreal Protocol on Substances that Deplete the Ozone Layer is completed and submitted for international ratification, which takes place quickly. The process started with a theory by Frank Sherwood Rowland and Mario Molina, who, in 1973 at the University of California, Irvine, wondered about the impact of CFCs as they accumulated in the atmosphere. In 1985 the British Antarctica Survey found that ozone levels were dropping, and 20 nations signed the Vienna Convention establishing a preliminary framework for international control of ozone-depleting substances. The CFC industry fought back. A DuPont spokesman claimed in 1986, for example, “that there is no immediate crisis that demands unilateral regulation.” Today, the Montreal Protocol, 25 years old in 2012, is seen as a model of international and scientific cooperation. Yet the reduction of CFCs hasnt fixed the ozone hole — it’s nearly as large as ever, and a new one has formed over the Arctic.