Peter Westbroek is professor emeritus in geophysiology at the University of Leiden. He initiated an international, interdisciplinary research programme on the role of limestone in global climate regulation and participated in the creation of Earth System Science. He was the first Dutch person since Erasmus to be appointed professor at the Collège de France in Paris, and in 2003 the European Geophysical Society awarded him the first Vladimir I. Vernadsky medal for his extraordinary contribution to biogeosciences. He has published several books, both scientific and for a broader audience, the best known being Life as a Geological Force. Dynamics of the Earth (1991).