The Atlantic Meridional Overturning Circulation (AMOC) may have been losing stability in the course of the last century, a new study by Niklas Boers, published in Nature Climate Change, suggests. The finding is worrying as well as a surprise. The AMOC, to which also the Gulf stream belongs, is responsible for the relatively mild temperatures in Europe and influences weather systems worldwide. A collapse of this ocean current system, which has so far not been considered likely under the current levels of global warming will therefore have severe consequences on global and especially European weather and climate. The study is part of the European TiPES project, coordinated by the University of Copenhagen, Denmark and the Potsdam Institute for Climate Impact Research, Germany.