Rahmstorf is a member of the Academia Europaea and served from 2004-2013 in the German Advisory Council on Global Change (WBGU). He was also one of the lead authors of the 4th Assessment Report of the IPCC. In 2007 he became an Honorary Fellow of the University of Wales and in 2010 a Fellow of the American Geophysical Union. In 2017 he was the first scientist outside the US to be awarded the Climate Communication Prize of the American Geophysical Union, and 2022 he received the Stephen H. Schneider Award for Outstanding Climate Science Communication. 2024 the European Geosciences Union awarded him the Alfred Wegener Medal, its most prestigious research award in the area atmosphere/ocean/hydrology.