has been head of the Bathymetry and Geodesy Group at AWI Bremerhaven since 1983 and responsible for the AWI bathymetric mapping programmes in Artic and Antarctic waters. As chief scientist, he conducted several expeditions with the German icebreaking RV Polarstern. He has been involved in the GEBCO programme since 1988, a member of the Guiding Committee since 1990 and chairman of the GEBCO Sub-Committee on Undersea Feature Names (SCUFN) since 2003. He is elected chairman of the IBCSO editorial board. Until 1983, he was research assistant for satellite geodesy at the Institute of Geodesy, University of Hannover.