A new study suggests the Gulf Stream system, known scientifically as the Atlantic Meridional Overturning Circulation (Amoc), could collapse as early as 2025, with catastrophic climate consequences. The research, published in Nature Communications, estimates a collapse window between 2025 and 2095, with a central estimate of 2050, if global carbon emissions are not reduced.
The Amoc, which carries warm water northwards and drives Atlantic currents, is already at its weakest in 1,600 years due to global heating. An influx of fresh water from melting Greenland ice is increasingly disrupting the currents. A collapse would cause severe disruptions to rains in India, South America and west Africa, increase storms and drop temperatures in Europe, and raise sea levels on the eastern US coast.
Lead author Prof Peter Ditlevsen of the University of Copenhagen said: 'I think we should be very worried. This would be a very, very large change. The Amoc has not been shut off for 12,000 years.' The study used sea surface temperature data from 1870 as a proxy for current strength and mapped it onto a tipping point model.
However, other scientists expressed caution. Prof Niklas Boers of the Potsdam Institute said uncertainties in the model and data are too large for a reliable estimate. Prof David Thornalley of University College London agreed there are large caveats but called the result 'very concerning' if robust. The Intergovernmental Panel on Climate Change previously concluded Amoc would not collapse this century.
All scientists agree the potential collapse is extremely concerning and should spur rapid cuts in carbon emissions. The Amoc is one of several climate tipping points that may already have been passed due to 1.1C of global heating.
