Nitrogen oxides affect the ozone layer

Paul Crutzen showed in 1970 that the nitrogen oxides NO and NO2 react catalytically (without themselves being consumed) with ozone. In this way they contribute to a reduction of the ozone content in the stratosphere.These nitrogen oxides are formed in the stratosphere from the decomposition of nitrous oxide N2O, which comes from microbiological transformations in the ground.The demonstration by Crutzen of the connection between microorganisms in the ground and the thickness of the ozone layer has contributed to the rapid development in the past few years of research into global biogeochemical cycles.


Too much ozone at the ground

The release of pollutants (nitrogen oxides, gaseous hydrocarbons, etc.) mainly from vehicles and industrial plants, can lead to greatly increased concentrations of ozone in the lowest layer of the atmosphere, eventually causing damage to plants and humans. Some pollutants, including methane from livestock, rice cultivation and other sources, spread over large parts of the earth and affect the ozone content of the troposphere worldwide. Paul Crutzen has laid bare the chemical mechanisms that affect the troposphere's ozone content. Since ozone is also a greenhouse gas, more ozone in the air contributes to a warmer climate.

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