We mourn the loss of Dr. Hans-Ulrich Wetzel. He was a scientist in the Remote Sensing and Geoinformatics Section and worked for the German Research Centre for Geosciences since its foundation. Directly after studying geology at the University of Greifswald, Hans-Ulrich Wetzel began working at the Central Institute for Physics of the Earth (ZIPE) as early as 1975. ZIPE was located as a non-university research institute of the Academy of Sciences of the GDR at the present site of the GFZ. In the late 1970s and early 1990s, Antarctica was one of Ulrich Wetzel's research focus. In East Antarctica, for example, he worked on the geological mapping of the region around Schirmacher Oasis.

Dr. Hans-Ulrich Wetzel was one of the pioneers in the use of remote sensing in geology and the elucidation of the relationship between geological structures visible in images and their formation and the development of the landscape. As a versatile geologist, he collaborated in this field with many scientists inside and outside the GFZ, and his research took him to Central Asia, China, Israel, Iran, Turkey, and southern Africa, among other places. Many colleagues will remember the satellite image maps he created for the field missions, which made it possible to assess the conditions in the study area somewhat better than with topographical maps alone. Ulrich Wetzel was the head of the working group "Remote Sensing in Geology" of the German Society for Photogrammetry and Remote Sensing (DGPF) for many years.

He was also deeply involved in the scientific cooperation with the Central Asian Institute for Applied Geosciences (ZAIAG), which was founded in 2004 by GFZ and the government of Kyrgyzstan and focuses on the fields of earth and environmental sciences, global change and natural hazards in Central Asia. Since the late 1990s, Uli Wetzel has made significant contributions to the founding and later development of ZAIAG. The institute is a partner institution for the GFZ and makes important contributions to research and development projects, knowledge transfer, and also to training programs in Central Asia. Among other things, Wetzel is a founding father of the ZAIAG-based High Altitude Observatory - Gottfried Merzbacher Station and led several annual expeditions. "With Hans-Ulrich Wetzel we lose an esteemed colleague who motivated numerous young scientists with his commitment and expertise and earned high recognition through his collaborative projects with partners in Central Asia" says ZAIAG's German Co-Director and long-time Head of the Scientific Board Division Dr. Oliver Bens.

Hans-Ulrich Wetzel was closely connected to Telegrafenberg for more than one generation. His father already worked here as a scientist. Uli Wetzel died a few weeks before his 69th birthday.