Professor Dr Paul Josef Crutzen

paul crutzen

MSc PhD DSc Stockholm

Professor Dr Paul Josef Crutzen

Honorary Fellow 


Paul Josef Crutzen is a Dutch chemist who received the 1995 chemistry prize for demonstrating, in 1970, that nitrogen oxide erodes the ozone layer, which protects the Earth from the sun’s ultraviolet radiation. He shared the prize with Mario J. Molina and F. Sherwood Rowland, who showed in 1974 that chlorofl uorocarbons (CFC) also destroy ozone. Between them, the three researchers may have saved the Earth from potential global disaster.

Crutzen was born in Amsterdam in 1933, and recalls attending school during the war years, especially the winter of famine in 1944–45, when several of his classmates died of hunger and disease. In 1946 he entered middle school, focusing on natural sciences, but admitting: “chemistry definitely was not one of my favourite subjects”, and went on to the Middelbare Technische School (MTS) to train as a civil engineer. His early career was at the Bridge Construction Bureau. In 1958 Crutzen married Finnish student Terttu Soininen and settled in Sweden. They have two daughters.

Longing for an academic career, Crutzen gained a job as a computer programmer at Stockholm University’s Department of Meteorology. He used his spare time to gain the equivalent of an MSc in mathematics, mathematical statistics, and meteorology and a PhD in meteorology. In 1965 he helped develop a numerical model of the oxygen allotrope distribution in the stratosphere, mesosphere and lower thermosphere. “This project got me interested in the photochemistry of atmospheric ozone”, he recalls.

While much of the work at Stockholm was aimed at acid rain, Crutzen says he was given free rein, and much help, in his ozone studies. He discovered that nitrous oxide (N2O), produced naturally by soil bacteria, rises into the stratosphere, where solar energy splits it into two reactive compounds, NO and NO2. These remain active for some time, breaking ozone (O3) down into molecular oxygen (O2). His research paved the way for the work of Molina, Rowland, and others, not least research into the effects of air traffi c releasing N2O into the atmosphere. Crutzen has worked at the European Space Research Organisation in Oxford, UK, the National Center for Atmospheric Research in Colorado, USA, and as director of the Atmospheric Chemistry Division, Max-Planck-Institute in Mainz, Germany. He was elected to academic societies in both Europe and the United States, including the Royal Swedish Academy of Sciences, the Royal Swedish Academy of Engineering and Academia Europaea.

This text and the picture of the Nobel Laureate were taken from the book: "NOBELS. Nobel Laureates photographed by Peter Badge" (WILEY-VCH, 2008)