Born 1949 in Bern (Switzerland). Study of physics Bern Univ., PhD in physics Bern Univ. (1982), Research Assistant at Scipps Institution of Oceanography, La Jolla/USA (1982-1985), scientist and working group leader at the Max Planck Institute for Meteorology (1985-1998), Senior Research Scientist at the Max Planck Institute for Biogeochemistry (1998-2003), Scientific Member and Director at Max Planck Institute for Biogeochemistry (since 2003), Honorary Professor at Friedrich Schiller Univ. of Jena (since 2005). Emeritus.