Erich Roeckner

The 2006 Vilhelm Bjerknes Medal is awarded to Erich Roeckner for his eminent contributions to the fields of atmospheric and oceanic modelling and process studies, and his outstanding leadership role in the development of a series of Earth climate system models.

Among the leading climate modeling centers of today no informed person would exclude the Max Planck Institute for Meteorology (MPI-M) in Hamburg, due to the most eminent stature of its series of ECHAM atmospheric general circulation, and more recently Earth climate system models. That this has happened is of course mainly a result of the contributions of its outstanding scientists. Among them was, and is, Erich Roeckner, the single most important person to develop the key tools at MPI-M needed to perform cutting-edge climate research, and also use them to improve our understanding of the Earth climate system.

After an education in meteorology at the University of Hamburg, the German Weather Service, and the Max Planck Institute for Aeronomy in Lindau, Erich Roeckner spent some time as a visiting scientist at the National Center for Atmospheric Research in Boulder, Colorado, USA. In 1973, he joined the Meteorological Institute of the University of Hamburg, first as a post-doctoral fellow, and between 1977 and 1990 as a faculty member. In 1991, Erich Roeckner joined MPI-M as a Senior Scientist.

With the ECHAM model, its superior performance, its flexibility for using it for various purposes, including process studies, the construction of climate change scenarios and paleoclimatic studies, the Max Planck Institute and its neighboring institutions, the German Climate Computing Center (DKRZ), the Meteorological Institute of the University of Hamburg, and the GKSS Research Center Geesthacht have had a world-class tool at their hands. For Erich Roeckner to be the “father” of ECHAM means two things – first the intimate knowledge of all aspects of a modern atmospheric general circulation model, and second the experience of and contributions to a broad range of applications of the model in different contexts. A review of Erich Roeckner’s long and significant list of publications shows that he has dealt with almost all internal aspects of a general circulation model. These issues comprise such diverse aspects as numerics, clouds, radiation, aerosols, boundary layer, oceanic mixed layer, diffusion, and advection. His contributions to understanding of the Earth climate system mechanisms are equally impressive. They include sensitivity studies, process studies, such as cloud optical depth feedbacks, tests of physical hypotheses related to, for instance, El Niño Southern Ocean oscillation (ENSO), the generation of climate scenarios, as well as reconstructions of recent past and paleoclimatic studies. It is due to a large measure to Erich Roeckner’s contributions, and also to his introduction of a great number of other scientists into the field, that our ever more crucial understanding of the Earth climate system has achieved the level that it today has.