Chemists Win Nobel Prize

Paul Crutzen, Mario Molina, and F. Sherwood Rowland


The three aforementioned scientists were awarded the 1995 Nobel Prize in Chemistry by the Royal Swedish Acadmey of Sciences for "their work in atmospheric chemistry, particularly concerning the formation and decomposition of ozone."



Previously, most researchers believed that the major cause of ozone depletion in the stratosphere was caused by catalytic reactions involving the OH and HO2 radicals. Crutzen, the director of the atmospheric chemistry division at Max Planck Institute for Chemistry in Mainz Germany, believed that this was not the case, and he was able to demonstrate the significance of nitrogen oxides (NO and NO2, collectively known as NOx). Crutzen saw a correlation between ozone depletion and NOx concentrations in the upper atmosphere, and was the first to propose how exactly the nitrogen oxides got to the stratosphere. He suggested nitrous oxide (N2O), a relatively inert gas that results from ocean and soil microbiological processes. Because of growing fertilizer use (fertilizer speeds up the nitrous oxide producing processes), Crutzen was able to point out that nitrous oxide could not and should not be ignored beneath the shadow of the fluorocarbon threat.

Molina and Rowland

Fluorocarbons, or, more specifically, chlorofluorocarbons (CFCs), are also very inert. They, like nitrous oxide, are able to migrate up to the stratosphere where they aid in the decomposition of ozone. Molina and Rowland learned of the process by which CFCs are broken apart by ultraviolent radiation and also how the products contribute to the depletion of the ozone layer. Published results predicted that, if nothing was done to stop the usage of CFCs, ozone depletion would continue at a rapid pace. Because of their warning, the United States banned CFCs as aerosol propellants in 1978 ... and more restrictions on these dangerous chemicals are still underway.


  • The Ozone Layer
  • Nitrous Oxide and Our Atmosphere
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