Paul sitting at his desk talking on the phone, looking down and pointing on a papper
Paul Crutzen, PhD student 1968 at MISU. Photo: Private

On January 28, Paul Crutzen passed away at the age of 87. He was born in 1933 in the Netherlands. After meeting his future wife Terttu from Finland in the 1950s, the couple decided to settle in Sweden and Gävle. After a year or so, they moved to Stockholm when Paul got a job as a programmer at International Meteorological Institute, Stockholms högskola. This gave him the opportunity to study mathematics and meteorology, in addition to his work. After a few years, he began his postgraduate studies in meteorology. In 1973, he defended his dissertation at Stockholm University, and later became an associate professor and continued to work for a few more years at the university.

Bert Bolin had an important role

During his years in Stockholm, Paul Crutzen worked with Bert Bolin - professor of meteorology and later first chairman of the UN's climate panel IPCC – as a supervisor. In an interview with Universitetsnytt 2009, Paul Crutzen said that Bert Bolin was of great significance to him:
“He gave me the freedom to do what I wanted. Early on, I understood that the explanation model that was used for the ozone in the atmosphere lacked important components, and I could look at it deeper.”
Paul Crutzen later came to work at various universities and research institutes, most notably the National Center for Atmospheric Research in Boulder, USA. Between 1980 and 2000, he led the Division of atmospheric chemistry at the Max Planck Institute for Chemistry in Mainz, Germany.

Nobel Prize for discoveries about the ozone layer

Paul Crutzen was awarded the 1995 Nobel Prize in Chemistry, alongside Mario Molina and Sherwood Rowland, for research into how the ozone in our atmosphere is formed and degraded. Paul Crutzen’s research showed above all the importance of nitrogen oxides for the ozone balance and how the ozone-depleting reactions are greatly enhanced by cloud particles in the stratosphere. This research contributed to the adoption of the Montreal Protocol, with the banning of emissions of freons and other ozone-depleting gases.

Anthropocene – the human age

Paul Crutzen was also one of the researchers who proposed the introduction of a new geological epoch, the anthropocene - the age of man. The era is characterized by the fact that the human impact on the earth's environment has had a decisive impact. He was also known for using the term "nuclear winter" (the global climate impact that would result from a nuclear war). Towards the end of his research career, Paul Crutzen also studied the link between increased biofuel use, air pollution and climate impact.
Over the years, Paul Crutzen maintained contact with Stockholm University and participated in various research projects with researchers at the university. Paul Crutzen visited Stockholm almost every year. In the academic year 1991–1992, he also spent time here as a Tage Erlander visiting researcher.

Huge loss for the scientific community

Professor emeritus Henning Rodhe was a doctoral student with Paul Crutzen – and then a lifelong friend and colleague. In a comment on the Max Plank Institute’s website, he says that Paul Crutzen’s death is a huge loss for the scientific community:
“He was an outstanding researcher. Paul laid the foundation for several basic research orientations that now inspire new generations of researchers.”

The article was first published in Swedish on Stockholm University’s website.

 

Read more:
Interview with Nobel Laureate Paul Crutzen 2009, on Stockholms University’s website

Interview with Paul Crutzen in Universitetsnytt 6 2009 (sidor 3–4, in Swedish)

Article by Sverker Sörlin in Dagens Nyheter (in Swedish)
Nobelpristagaren som gav världen en knuff