A new study suggests the Gulf Stream system, known scientifically as the Atlantic Meridional Overturning Circulation (Amoc), could collapse as early as 2025, bringing catastrophic climate impacts. The research estimates a timescale for collapse between 2025 and 2095, with a central estimate of 2050, if global carbon emissions are not reduced.
Amoc carries warm ocean water northwards, where it cools and sinks, driving Atlantic currents. However, an influx of fresh water from accelerating melting of Greenland's ice cap is smothering these currents. The system was already known to be at its weakest in 1,600 years due to global heating, with researchers spotting warning signs of a tipping point in 2021.
A collapse would have disastrous consequences worldwide, including severe disruption of rains that billions depend on for food in India, South America and west Africa. It would increase storms and drop temperatures in Europe, raise sea levels on the eastern coast of North America, and further endanger the Amazon rainforest and Antarctic ice sheets.
Professor Peter Ditlevsen of the University of Copenhagen, who led the study, 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, published in Nature Communications, used sea surface temperature data from 1870 as a proxy for Amoc strength and mapped it onto a tipping point model.
Other scientists expressed caution, noting that assumptions about how the tipping point would play out and uncertainties in the data are too large for a reliable estimate. Professor Niklas Boers of the Potsdam Institute said the uncertainties make it impossible to provide a reliable timing. However, all agreed the prospect of an Amoc collapse is extremely concerning and should spur rapid cuts in carbon emissions.
