Atlantic Ocean Currents at Risk: New Research Signals Higher Collapse Probability

The critical Atlantic current system is now considered far more likely to collapse than previously estimated. New scientific research shows that climate models predicting the most severe slowdown are, in fact, the most accurate.

Experts have described these findings as “very concerning,” warning that a collapse could trigger catastrophic climate impacts across Europe, Africa, and the Americas.

What Is the Atlantic Meridional Overturning Circulation (AMOC)?

The Atlantic Meridional Overturning Circulation (AMOC) is a vital component of Earth’s climate system. It transports warm tropical water northward to Europe and the Arctic, where it cools, sinks, and flows back southward at depth.

However, due to the escalating climate crisis, the AMOC is already at its weakest point in over 1,600 years. Scientists previously identified early warning signs of a potential tipping point in 2021, and geological evidence confirms that this system has collapsed before in Earth’s history.

Climate Models Reveal Alarming Slowdown Trends

Climate scientists rely on multiple computer models to predict future changes, but AMOC projections have historically varied widely. Some models suggest little to no slowdown by 2100, while others predict a dramatic decline of up to 65%—even under net-zero emissions scenarios.

By combining real-world ocean data with these models, researchers have significantly reduced uncertainty. The updated projections now estimate a slowdown of 42% to 58% by 2100, a level that makes collapse highly likely.

Global Impacts of an AMOC Collapse

A collapse of the AMOC would have severe and far-reaching consequences, including:

• Disruption of tropical rainfall patterns, threatening global food security
• Intensified extreme weather, including colder winters and droughts in western Europe
• Accelerated sea-level rise of 50–100 cm along Atlantic coastlines
• Widespread ecological and economic damage across multiple continents

These changes would affect millions of people and reshape global climate systems.

Dr Valentin Portmann, at the Inria Centre de recherche Bordeaux Sud-Ouest in France and who led the new research, said: “We found that the Amoc is going to decline more than expected compared to the average of all climate models. This means we have an Amoc that is closer to a tipping point.”

Prof Stefan Rahmstorf, at the Potsdam Institute for Climate Impact Research in Germany, said: “This is an important and very concerning result. It shows that the ‘pessimistic’ models, which show a strong weakening of the Amoc by 2100, are, unfortunately, the realistic ones, in that they agree better with observational data.”

He added: “I now am increasingly worried that we may well pass that Amoc shutdown tipping point, where it becomes inevitable, in the middle of this century, which is quite close.”

Why the AMOC Is Slowing Down

The slowdown is driven largely by global heating, particularly rapid warming in the Arctic. As ocean temperatures rise:

• Water becomes less dense and sinks more slowly
• Increased rainfall dilutes salty ocean water, further reducing density
• This creates a feedback loop that weakens the overall circulation

This complex interplay of temperature and salinity makes the AMOC especially difficult to model accurately.

Breakthrough Research Improves Prediction Accuracy

The latest study, published in the journal Science Advances, introduces a more reliable approach to evaluating climate models. Researchers used a statistical method called ridge regression, which proved highly effective in identifying the most accurate projections.

This method focuses on how well models simulate surface salinity in the South Atlantic—a key factor in AMOC behaviour. Scientists say this approach significantly strengthens confidence in the findings.

Expert Warnings: “Collapse Must Be Avoided at All Costs”

Prof Stefan Rahmstorf warns that collapse must be avoided “at all costs.”

“I argued this when we thought the chance of an Amoc shutdown was maybe 5%, and even then we were saying that risk is too high, given the massive impacts. Now it looks like it’s more than 50%. The most dramatic and drastic climate changes we see in the last 100,000 years of Earth history have been when the Amoc switched to a different state.”

He also notes that current models may underestimate the risk, as they often exclude the impact of freshwater from melting Greenland ice, which could further accelerate the slowdown.

“That is one additional factor that means the reality is probably still worse.”

Why This Matters Now

Although precise predictions remain challenging due to the AMOC’s complexity, scientists agree that significant weakening is already underway. Even without full collapse, this trend could bring major climate disruptions within decades.

Understanding and addressing the risks to the AMOC is critical—not only for climate stability but for the future of ecosystems, economies, and communities worldwide.

Support UK Rewilding Efforts

At Natural World Fund, we support science-led action to address the climate crisis and protect critical Earth systems like the Atlantic Meridional Overturning Circulation. By tackling greenhouse gas emissions, promoting sustainable practices, and safeguarding ocean health, we can help reduce the risk of irreversible tipping points. Protecting our climate system today is essential to securing a stable, resilient future for communities, ecosystems, and generations to come.

If you care about restoring native wildlife in the UK, support the work of Natural World Fund today.