For years, chemicals used in hair spray and refrigerators have been wreaking havoc with the ozone layer, the protective shroud that protects us from the sun’s harmful UV rays. But it wasn’t until 1974 that people started paying attention.
This was the year that Mexican scientist Mario Molina published a paper showing that CFCs — widely used in refrigerator coolers, spray paint, deodorant sprays and other aerosol products — are depleting the ozone layer. The consequences were dire, because without the ozone layer to help protect us from the sun, our planet would be uninhabitable. His research has helped change global environmental policy.
To honor Molina’s groundbreaking efforts to combat an environmental disaster, Google dedicated its own doodle to Molina on the Nobel laureate’s 80th birthday.
Born on March 19, 1943, in Mexico City, Molina was drawn to science at an early age, converting the bathroom in his home into a makeshift laboratory for his chemistry kits.
Molina wrote in her autobiography about: Nobel site. “I still remember my excitement when I first glimpsed paramecia and amoeba through a rather primitive toy microscope.”
After being sent to a Swiss boarding school at the age of 11, Molina returned to Mexico to study a chemical engineering program at the National Autonomous University of Mexico before earning a PhD in physical chemistry from the University of California, Berkeley, in 1972.
A year later, while working with F. Sherwood Rowland of the University of California, Irvine, Molina found that CFCs in the upper atmosphere could be broken down by ultraviolet light, releasing chlorine atoms, which destroy ozone molecules. Their findings were published in the journal Nature in 1974.
Their findings were denounced by CFC-dependent industries, with one company executive claiming that the couple’s theory was “orchestrated by the KGB’s Ministry of Disinformation”. But in 1985, British researchers discovered a huge hole in the ozone layer over Antarctica.
These findings led governments around the world to come together in the 1980s and sign a treaty called the Montreal Protocol in order to phase out the use of substances harmful to the ozone layer. Science Journal named The agreement as “the most successful international effort to combat climate change and environmental degradation”.
In recognition of their work, Molina and Rowland shared the 1995 Nobel Prize in Chemistry with Paul J. Crutzen of the Max Planck Institute in Germany. In announcing the award, the Royal Swedish Academy of Sciences said, “The three researchers contributed to saving us from a global environmental problem that could have serious consequences.”
In 2013, President Barack Obama awarded Molina the Presidential Medal of Freedom, the United States’ highest civilian honor.
Molina died of a heart attack in 2020 at the age of 77.