Ozone depletion research wins Nobel.

For their work elucidating how Earth's protective ozone layer forms and decomposes, three scientists received this year's Nobel Prize in Chemistry.

The Nobel committee honored Paul Crutzen, a Dutch scientist at the Max Planck Institute for Chemistry in Mainz, Germany; Mario J. Molina of the Massachusetts Institute of Technology; and F. Sherwood Rowland of the University of California, Irvine, for showing "how sensitive the ozone layer is to the influence of anthropogenic emissions of certain compounds."

In explaining the mechanisms affecting the ozone layer's thickness, said the committee, the three scientists have contributed to "our salvation from a global environmental problem that could have catastrophic consequences."

The stratospheric ozone layer consists of three-atom oxygen molecules (O3) sparsely distributed more than 15 kilometers above sea level. Though relatively few in number, ozone molecules capture much of the sun's ultraviolet rays, protecting life on Earth from their damaging effects.

In 1970, Crutzen first showed that nitrogen oxides (NOx)--produced by decaying nitrous oxide from soil-borne microbes--react catalytically with ozone, hastening its depletion. His findings, the committee said, sparked research on "global biogeochemical cycles" as well as the effects on the stratosphere of nitrogen oxide--spewing supersonic transport planes.

In 1974, Molina and Rowland postulated that human-made chlorofluorocarbons--widely used in spray cans, refrigerators, and air conditioners--could, in the stratosphere, transform into ozone-depleting agents. Within a decade, scientists worldwide acknowledged the impact of certain industrial gases on the upper atmosphere, prompting nations to ban production of the most environmentally noxious agents.

"This is really a prize for the scientific community," says Molina, "which has done an excellent job of dealing with this global environmental issue."

Calling the award "highly appropriate," Daniel L. Albritton, an atmospheric chemist at the National Oceanic and Atmospheric Administration in Boulder, Colo., says the recognition highlights "basic science also done for the benefit of humankind."

"Traditional chemistry has mainly involved laboratory work and theoretical calculations," says Rowland. "This award validates the field of environmental chemistry." Noting that this now applied research began as basic science, Rowland adds that this Nobel strengthens the case for "curiosity-driven" investigations.

"We were trying to figure out how the world works, without thinking specifically about how to use the results," he says. "There are distinct advantages to letting people try to understand things, and in doing so pursue questions that might later lead to applications."

Perhaps a better term for such research, Rowland says, would be "understanding-driven."