The Atlantic Meridional Overturning Circulation (AMOC) is a vast system of ocean currents that helps to distribute heat around the world. By transporting warm water from the tropics northwards and cold water back southwards, the AMOC keeps Europe warm and plays a role in controlling global rainfall. It connects into an even larger network of ocean currents that continuously moves water, nutrients and carbon around the world. Now, the AMOC is under threat from human-caused climate change, as warming seas, melting ice and increased rainfall upset the temperature and salt balance of the North Atlantic. Scientists have warned that the ocean currents are slowing down – and could eventually become so frail that they no longer transport heat around the globe. A growing body of research has suggested that, with enough warming, the AMOC could reach a “tipping point” and transition to a weak state for many centuries. The Intergovernmental Panel on Climate Change (IPCC) has projected that the AMOC will decline over the course of the 21st century as the world warms. However, whether – and when – currents might “collapse” remains a subject of debate. The IPCC says a “collapse” before 2100 is unlikely. However, some scientists have argued climate change could force the AMOC past a “point of no return” over the coming decades that could usher it towards a “shutdown” next century. A major slowdown or “tipping” of the AMOC could have grave consequences for European temperatures, causing them to plunge – despite global warming. It…
