Born      19 April 1966, Augsburg, Germany
Family    Married, two children

Prof. Bjorn Stevens is a director of the Max-Planck-Institute for Meteorology where he leads the Atmosphere in the Earth System Department. He is also a professor (§17) at the University of Hamburg.

His main field of interest is in the way atmospheric water - particularly in the form of clouds - shapes climate. His contributions to understanding how turbulent mixing and cloud-microphysical processes influence cloud amount have been instrumental in helping to understand how clouds respond to warming, and how radiative forcing responds to aerosol perturbations, both of which are fundamental to our present comprehension of climate change.

Prof. Stevens has initiated and led a number of international field studies, and established a programme of ongoing measurements through the creation of the Barbados Cloud Observatory - the only facility of its type in the broader tropics. His measurements have identified new forms of clouds that arise in response to precipitation, provided the first quantification of cloud top mixing, and illustrated and quantified the vertical structure of large-scale vertical motion fields in the tropics and sub-tropics. His theoretical contributions have articulated ways in which clouds respond to mixing, outlined new ways of thinking about aerosol forcing, and provided novel frameworks for understanding how clouds maintain the depth of the trade-wind layer. Prof. Stevens was one of the architects of the sixth phase of the coupled model intercomparison project (CMIP6), and he co-conceived and co-led the first ever intercomparison of global storm resolving models. Through these efforts, and his initiation and leadership of the German national project: "High Definition Clouds and Precipitation for Climate Prediction" he has helped outline the development pathway for a new generation of climate models.

Prof. Stevens served as a lead-author of Chapter 7, "Cloud and Aerosols" for the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Presently Prof Stevens co-leads the WCRP Grand Science Challenge on Clouds, Circulation and Climate Sensitivity. He serves on a number of international advisory boards, has served as editor of leading journals in his field and has been honored by a number of lectureships and awards, including the Clarence Leroy Meisinger Award of the American Meteorological Society, as well as fellowships from the Advanced Study Program of the National Center for Atmospheric Research, and the Alexander von Humboldt Society.