Atlantic Current System on the Brink
According to a growing body of research, a vast system of Atlantic currents that delivers warmth to northern Europe is at risk of collapse. The latest study to warn of its demise finds that there is at least a 10 percent chance that a collapse may already be “locked in.” The study, published at the E360 Digest on July 7, 2026, presents new modeling that underscores the vulnerability of the Atlantic Meridional Overturning Circulation (AMOC).
Understanding the AMOC
The Atlantic Meridional Overturning Circulation, or AMOC, ferries warm water from the tropics to northern Europe. As the water cools, it becomes more dense and drops to the ocean depths, where it flows south, back toward the tropics. However, as oceans warm, those waters are not so cool, nor so dense, as they once were, causing the system of ocean circulation to slow down. The melting of the Greenland ice sheet is introducing large amounts of fresh water, which is less dense than salty water, further slowing circulation.
Potential Impact of a Collapse
By one estimate, if the AMOC were to collapse, its flow slowing to a near halt, temperatures in northern Europe would drop by 9 to 27 degrees F (5 to 15 degrees C). This would have severe consequences for agriculture, ecosystems, and human societies across the region.
New Modeling and Risk Assessment
The new modeling study found that even in a scenario where global emissions peaked in 2025 and the melting of the Greenland ice sheet raises sea levels by just 2 inches this century, there is a 10 percent chance that the AMOC will eventually collapse. In scenarios where the Greenland ice sheet unleashes more meltwater, the probability of collapse rises to 23 percent, according to the study, which has not yet undergone peer review.
Call for Urgent Action
Coauthor Tim Lenton, of the University of Exeter, stated: “What the model is saying to me is, ‘Let’s do everything in our power to get to net-zero as quickly as possible to try to keep this probability down at the 10 percent level.’” This highlights the urgency of reducing greenhouse gas emissions to avoid triggering a tipping point in the climate system.