Thirty state-of-the-art IPCC-climate models predict dramatically different climates for the Northern Hemisphere, especially Europe. An analysis of the range of responses now reveals that the differences are mostly down to the individual model's simulations of changes to the North Atlantic ocean currents and not only—as normally assumed—atmospheric changes. The work, by Katinka Bellomo, National Research Council of Italy, Institute of Atmospheric Sciences and Climate, and colleagues is published today in Nature Communications and is part of the European science collaboration, TiPES, coordinated by the University of Copenhagen.