Nobel Prize winning chemist Mario Molina published his famous ozone paper in the journal Nature in 1974.

As a child, Mario Molina converted a bathroom in his family home in Mexico City into a chemistry lab. Years later, his work with chemistry earned him a Nobel Prize. Molina was awarded the Nobel prize with two other scientists for their work in understanding how ozone is formed and depleted—particularly by chemicals such as chlorofluorocarbons (CFCs). In 1973, when Molina began researching CFCs as part of a research group at Berkley, it was thought that CFCs had no real effect on the environment. These industrial chemicals, which had been accumulating in the atmosphere from a variety of sources such as aerosol cans and refrigerators, were known to be chemically inert, but no one had investigated how they reacted in the atmosphere. Molina was familiar with the chemical properties of CFCs and chose to explore the effects they might have on the atmosphere primarily as a way to learn a new field—atmospheric chemistry. What began as a routine and fairly uninteresting research project quickly turned into an important one as Molina and fellow researchers realized that the chemicals given off when CFCs were decomposed were able to destroy ozone in the Earth’s atmosphere. Molina consulted with atmospheric scientists and soon realized that CFCs could have the serious effect of depleting the protective ozone layer surrounding the Earth.

Molina and his colleagues wrote a paper describing their work, which first appeared in the journal Nature on this day in 1974. Recognizing the environmental impact of this issue, they also communicated their findings to policy makers and to the news media. The work of Molina and his fellow researchers became the basis for the Montreal Protocol to Reduce Substances that Deplete the Ozone Layer, which was signed by 27 nations in 1987. Today, the ozone depletion problem is carefully monitored by scientists. Thus a research project that started out as simple scientific curiosity led to both an important scientific discovery and political action that has helped to prevent an environmental crisis. In 1995, Molina and his fellow researchers were awarded the Nobel Prize in Chemistry for their work.

Science NetLinks
The Science Update Ozone Fill-up (6–12) explores creative ideas for closing the hole in the ozone layer that was discovered over Antarctica in the 1980s.

The Science Update Asian Brown Cloud (6–12) discusses an effort to measure the air pollution over Asia and assess its impact on humans and the environment.

ARTSEDGE
Students learn about the atmosphere through movement and dance in Sphere’s Density Dance (K–4).

Xpeditions
Students learn about how environmental problems affect the polar regions in Environmental Issues in the Polar Regions (9–12).