The Atlantic Meridional Overturning Current (AMOC) is part of a conveyor belt of currents that circulate water around the world, regulating weather and sea level. Professor Peter Ditlevsen from Copenhagen's Niels Bohr Institute is co-author of a study, published this week in Nature Communications which predicts AMOC may dramatically slow down and then turn off, as soon as 2025 and likely by the end of the century. The collapse of this system will have enormous implications, including more extreme winters and sea level rises affecting parts of Europe and the US, and a shifting of the monsoon in the tropics.