Manufacturers began to phase out chlorofluorocarbons in the late 1980s, prompted by the discovery of an ozone "hole" over Antarctica that formed each winter in response to weather conditions and the falling worldwide levels of ozone. The Montreal Protocol, a landmark international agreement to phase out CFC products, was signed by the United States and other nations in 1987.
The protocol was proof that nations could unite to address common environmental threats, Rowland contended. "People have worked together to solve the problem," he said.
Rowland considered the phase-out of CFCs his greatest achievement, Blake said. His receiving the Nobel Prize, alongside Molina and Paul J. Crutzen of the Netherlands, in 1995 was icing on the cake. In his Nobel banquet speech, Rowland noted mankind's long fascination with the atmosphere. But it was his own dogged curiosity that spared the world from a potential environmental crisis.
"He was the perfect spokesperson for this issue," Blake said. "He was austere, well-spoken and had a lot of confidence. He didn't get emotional" when challenged.