| 1 | Name: | Dr. Paul J. Crutzen | |
| Institution: | Max Planck Institute for Chemistry | ||
| Year Elected: | 2007 | ||
| Class: | 1. Mathematical and Physical Sciences | ||
| Subdivision: | 102. Chemistry and Chemical Biochemistry | ||
| Residency: | International | ||
| Living? : | Deceased | ||
| Birth Date: | 1933 | ||
| Death Date: | January 28, 2021 | ||
Paul Crutzen was a professor at the Scripps Institution of Oceanography's Center for Atmospheric Sciences from 1992 to 2008. He was also Professor Emeritus at the Institute for Marine and Atmospheric Sciences, Utrecht University, and the former director of the Max Planck Institute for Chemistry. He has made substantial and fundamental contributions to our understanding of the formation and decomposition of ozone - processes that are also affected by our emissions of different kinds of gas. In particular, he has shown the importance of nitrogen oxides for the ozone balance. Crutzen has also made contributions to the understanding of how the reactions that decompose ozone are considerably reinforced by cloud particles in the stratosphere. That the dilution of the ozone layer is strongest just above the poles of the earth - in particular over Antarctica - is due to this effect. The extremely low temperatures lead to the creation of a very large amount of cloud particles. Research on the chemical mechanisms in the ozone layer has shown signs of the negative impact of humans. There are now far-reaching international agreements on the prohibition of emission of freons and other gases destroying ozone in the so-called Montreal Protocol. Crutzen has also studied how ozone is created in the lower stratum of the atmosphere, the troposphere, where the amount of ozone has increased in the last century due to car exhausts and other emissions. Besides contributing to the greenhouse effect, ozone close to the ground also causes damage to crops and human health. Paul Crutzen shared the 1995 Nobel Prize in Chemistry with Mario Molina and Sherwood Rowland. His most recent interests are in the following areas: global modeling of atmospheric chemical processes (2-D, 3-D) for troposphere, stratosphere and lower mesosphere; interactions of atmospheric chemistry with climate; studies of the potential role of halogen photochemistry with ozone in the marine boundary layer; and tropospheric chemistry, including the role of biomass burning in the tropics and subtropics. More recently Crutzen has involved himself with studies of geo-engineering to reduce the heating of Earth's climate by carbon dioxide emissions. He also published a paper showing that the production of biofuels (e.g. ethanol from maize and biodiesel from rapeseed) to replace fossil fuels may not cool climate. Crutzen also proposed that over the past 200 years human activities have grown so much that the introduction of a new geologic epoch, the Anthropocene, is justified. He died on January 28, 2021. | |||