The ocean circulation that keeps our relatively northern corner of Europe warm(ish) is often likened to a gigantic conveyor belt bringing warm equatorial water northwards at the surface, balanced by cold southward flow at great depth. The Atlantic Meridional Overturning Circulation, or AMOC for short, brings heat energy northward at the equivalent rate of 10 Hiroshima bombs every second and keeps our weather mild, and just a little bit too damp, and is critical to the wider climate.
New research has provided important long-term context for scientists’ observations of these Atlantic currents that bring warmth and climatic stability to our shores, with concerning implications for the coming century. Changes in the AMOC in the geologic past have caused significant local and global impacts, and for several decades now oceanographers have been monitoring its strength.
Related: Atlantic Ocean circulation at weakest in a millennium, say scientists
Andrew Meijers is a physical oceanographer at the British Antarctic Survey. He is deputy science leader of the Polar Oceans team and leads the Orchestra research program studying ocean circulation and its impact on climate