Prof. em. Dr. Werner Alpers

Werner Alpers studied physics at the University of Hamburg (Germany), Zurich (Switzerland), and Madison, Wisconsin (USA). In 1962 he received the diploma degree in physics (Dipl.- Phys.) from the University of Hamburg, in 1964 the Master of Science degree (M. S.) in physics from the University of Wisconsin, and in 1967 the Ph. D. degree (Dr. rer. nat.) in theoretical physics (elementary particle physics) from the University of Hamburg. From February 1968 to September 1970 he was with the European Space Research Institute (ESRIN) of the European Space Organization (ESRO) in Frascati (Italy) and from October 1970 to September 1973 with the Max-Planck-Institute for Physics and Astrophysics, Institute for Extraterrestrial Physics, in Garching near Munich, Germany, where he carried out research in the field of space physics and cosmic ray physics. In 1973 he switched to oceanography and has worked since then in the field of remote sensing of the ocean. From 1973 to 1985 he worked as a scientist at the University of Hamburg and the Max-Planck-Institute for Meteorology in Hamburg, from 1985 to 1989 as an Associate Professor (C3) at the Department of Physics and Electrical Engineering of the University of Bremen, Germany, and from 1989 to 2001 as a Full Professor (C4) at the Institute of Oceanography of the University of Hamburg, where he established and headed the research group "Satellite Oceanography". From 1998 to 2001 he was also the Managing Director of the Institute of Oceanography. His research group was engaged in fundamental research aimed at preparing satellite and Spaceshuttle missions for ocean observations. The research activities included radar backscattering experiments in the laboratory (at a wind wave tank) and at sea (from the “Research Platform North Sea”) and from airplanes and helicopters. Another mayor topic was the development of theoretical models to describe the interaction of microwaves (radar beams) with the ocean surface, which serve as basis for retrieving information on the ocean from satellite data. Werner Alpers and Cliff Rufenach from the USA were the first to demonstrate how one can obtain information on ocean wave spectra by using a synthetic aperture radars (SAR). Furthermore, Werner Alpers was the first to develop a theory, which explains why SARs are capable to provide information also on underwater sand banks and internal waves in the ocean.

Already in 1977 he analyzed, together with scientists of the National Oceanic and Atmospheric Administration (NOAA) in the US, data of the American Geos-3 satellite (launched 1975), and since 1998 data of the American Seasat satellite (launched 1978). Furthermore, he participated as a Principal Investigator in three Spaceshuttle missions: Spacelab-1 (1983), SIR-B (1984), and SIR-C/X-SAR (1994). In 1992 he organized on behalf of the European Space Agency (ESA) a measurement campaign during which radar images were taken simultaneously over seral ocean areas by the European Remote Sensing Satellite ERS-1 (launched 1991) and the Russian reconnaissance satellite ALMAZ-1 (launched 1991). The aim of this campaign was to find out which of the two SARs onboard both satellites were best suited to image ocean waves. The data were analyzed jointly in Hamburg and Moscow, from which a long term cooperation with Russian scientists evolved.

He has authored or co-authored more than 130 papers in peer reviewed journals and books and more than 110 papers in conference proceedings dealing primarily with remote sensing of the ocean and the atmosphere above the ocean. Two of his main scientific achievements are 1) the discovery of internal waves in the Strait of Messina (together with Ettore Salusti of the University of Rome), and 2) showing that very thin surface films (one molecular layer thick) can cause damping also of long ocean waves (together with the chemist Heinrich Hühnerfuss of the University of Hamburg). He also served in several advisory committees of the German Ministry of Science and Technology, the German Science Foundation, the European Science Foundation, and ESA dealing with satellite-based earth observation. In particular, he was involved from the beginning in the planning of the European earth observation satellites ERS-1 (launched 1991), ERS-2 (launched 1995) and Envisat (launched 2002) and was a Principal Investigator in all of these ESA satellite missions. In 1999 he organized as General Chairman the International Geoscience and Remote Sensing Symposium (IGARSS’99) in the Congress Center of Hamburg.

After his retirement from the University of Hamburg in 2001 he has continued carrying out research in the field of satellite oceanography at the University of Hamburg. He closely cooperates with scientists in Mainland China, Taiwan, Russia, USA, France, and Norway. In recent years his research interest has been focused on studies of meso-scale atmospheric phenomena in the marine boundary layer using SAR. In addition to research, he also is engaged in teaching, mainly as a lecturer in remote sensing training courses organized by ESA and other institutions, e.g., in China (Qingdoa, Hangzhou, Shanghai, Hong Kong), but also in other countries (Germany, Netherlands, Taiwan, South Korea, Vietnam, India, and Mexico). Werner Alpers is since 1999 Visiting Professor at the Ocean University of China in Qingdao and received in 2008 the National Friendship Award of the People’s Republic of China.

• Remote sensing of the ocean