Physicist and science YouTuber Dr. Ben Miles says one of the planet’s most important ocean systems is now showing signs that scientists have been trying to identify for decades: an early warning signal that the Atlantic Meridional Overturning Circulation, known as the AMOC, may be moving closer to a dangerous tipping point.
In a new video, Miles explained that this ocean current system, which helps keep much of Northern Europe far warmer than its latitude would suggest, is now believed to be at its weakest point in roughly 1,600 years.
The concern is not simply that the current is slowing. According to Miles, new research by René M. van Westen and Henk A. Dijkstra, published on February 26, 2026, shows that changes in the Gulf Stream’s path could act as a visible early warning sign before a future AMOC collapse.
That is a big deal because the AMOC is not just another climate feature. It is a planetary-scale heat engine, moving warm tropical water northward and helping shape weather, agriculture, sea ice, rainfall patterns, and marine food chains across large parts of the world.
The Current That Keeps Europe Warmer Than It Should Be
Miles began by pointing out something many people forget: Britain sits at about the same latitude as parts of Siberia, while Norway lines up with the southern tip of Greenland.
By geography alone, he said, Northern Europe should be much colder for much of the year. Instead, it is kept relatively mild because the Atlantic carries tropical heat northward.
That system begins around the Gulf of Mexico, where warm surface water is pushed north along the U.S. East Coast. This is the Gulf Stream, the most familiar part of the larger AMOC system.
Miles said that by the time the flow reaches the open Atlantic, it is moving about 80 million cubic meters of water every second in a current roughly 150 kilometers wide.
As that warm water travels north, it releases heat into the atmosphere. That heat is carried toward Europe, softening winters that would otherwise be far harsher.
But the AMOC is not just a surface current. Miles explained that as the water reaches the North Atlantic, it cools, evaporates, becomes saltier and denser, then sinks into the deep ocean near the Norwegian coast before flowing southward along the seafloor.
A single molecule of water may take about 1,000 years to complete the full circuit, he said.
The scale of the system is almost hard to picture. Miles said the AMOC moves roughly one petawatt of thermal energy every second, about 50 times the total energy consumption of human civilization.
Why The System Is Weakening
Miles said the AMOC depends on northern Atlantic water becoming dense enough to sink.
Water gets denser when it cools, and saltier water is denser than freshwater. That sinking motion helps pull the whole circulation system along.
The problem, according to Miles, is that freshwater from the melting Greenland ice sheet is now entering the North Atlantic at a growing rate. Because freshwater is less dense than salty water, it weakens the contrast that normally helps cool Atlantic water sink.
That does not immediately stop the current. Miles said the system can absorb a lot of freshwater and keep going, though at reduced strength.
But only up to a point.
Beyond that point, he said, the system can shift abruptly rather than gradually. That is what makes scientists worry about a tipping point, where the current does not merely weaken, but collapses into a different state.
Miles noted that something similar is believed to have happened about 12,900 years ago during the Younger Dryas, when a large freshwater disruption in the North Atlantic helped trigger a sudden return to near-glacial conditions in the region for more than 1,000 years.
The worry today is not that history repeats in exactly the same way, but that the same type of physical system may still be vulnerable to the same basic pressure.
A New Warning Signal Hidden In The Gulf Stream
For years, Miles said, the honest answer to “how close are we?” was that scientists did not really know.
The AMOC has been measured directly by the RAPID array since 2004, but Miles explained that knowing the current is weakening does not automatically tell scientists how close it is to collapse. A system can slow down for a long time without crossing its threshold.
What researchers needed, he said, was less like a speedometer and more like a fuel gauge.
That is where the new paper by van Westen and Dijkstra comes in.
Their study, titled “Abrupt Gulf Stream Path Changes Are A Precursor To A Collapse Of The Atlantic Meridional Overturning Circulation,” investigated whether changes in the Gulf Stream’s path can reveal what is happening deeper in the AMOC.
According to the article’s abstract, the researchers used a high-resolution ocean simulation and found that as the AMOC weakened under slowly increasing freshwater forcing, the Gulf Stream near Cape Hatteras shifted northward.
The most dramatic part came later in the model: the Gulf Stream suddenly moved 219 kilometers north within two years, a rapid shift that happened a few decades before the simulated AMOC collapse.
Miles explained that this matters because the Gulf Stream’s position is partly anchored by the deep western boundary current, the deep return flow of the AMOC along the seafloor. If that deeper current weakens, the Gulf Stream should begin to drift north.
Older climate models often missed this behavior because they used grid squares around 100 kilometers wide. Miles said van Westen and Dijkstra used a 10-kilometer grid, about ten times finer, which made the model roughly 1,000 times more expensive to run.
Even on the Dutch national supercomputer Snellius, he said, it took six months.
Scientists Found The Pattern In Real Observations
After building the model, the researchers looked for the same pattern in the real world.
Miles said satellite altimetry data from 1993 to 2024 and subsurface temperature observations going back to 1965 both show a statistically significant northward drift of the Gulf Stream near Cape Hatteras.
According to Miles, that drift is about 53 kilometers since 1993.
The study’s abstract also says satellite altimetry shows a significant Gulf Stream trend near Cape Hatteras from 1993 to 2024, while subsurface temperature observations from 1965 to 2024 confirm the same broader pattern.
Miles said that does not mean scientists can now give an exact countdown to collapse. The real ocean is more complicated than any model, with warming, shifting winds, changing atmospheric circulation, and freshwater input all happening together.
Still, he said the research finally gives scientists a physically grounded, satellite-observable proxy for AMOC health.
In simpler terms, the Gulf Stream’s movement may be a visible surface clue about a deep ocean system that is otherwise very hard to watch in real time.
That is the fascinating and unsettling part. Miles said humans may have been watching the right data for 30 years without fully understanding what it meant.
What Collapse Could Mean
Miles said an AMOC collapse would be one of the most disruptive climate events in recorded human history.
Without the northward heat transport, he said average winter temperatures across Europe could drop by about 10 degrees Celsius. Sea ice could spread southward, affecting coastlines around Britain and Northern Europe, while London could see temperatures as low as minus 20 degrees Celsius in extreme scenarios.
Scandinavia, Miles said, could become colder than Siberia, and growing seasons across Northern Europe could stop working the way they do now.
But the effects would not be limited to Europe.
As the North Atlantic cools, tropical rain belts could shift, weakening monsoon systems that supply seasonal rainfall to West Africa and South Asia. Miles warned that this could disrupt food supplies for more than a billion people.
The AMOC also helps drive upwelling of cold, nutrient-rich deep water. If that weakens, surface waters could lose the nutrients that feed phytoplankton, which support much of the marine food web.
This is why AMOC research tends to sound alarming. It is not about one cold winter or one bad storm season. It is about a circulation system that touches climate, food, oceans, and economies at once.
A Slow Warning That Is Easy To Ignore
Miles ended his report with a broader warning about how humans respond to risk.
He said people understand “asymmetric upside,” the idea that a small bet could bring a huge reward, like winning the lottery or investing early in a major company. But he argued that societies are much worse at dealing with “asymmetric downside,” where small changes in behavior or spending might prevent a massive disaster.
That may be the most important point in the entire discussion. AMOC collapse is not a Hollywood-style threat that arrives all at once with dramatic music. It is slower, stranger, and easier to normalize.
Miles compared it to a quiet version of what some thinkers call a “great filter,” a kind of barrier that civilizations fail to survive not because they missed a sudden catastrophe, but because they ignored a slow one.
The new van Westen and Dijkstra paper does not prove that collapse is imminent. Miles was careful to say the research gives scientists a mechanism and model, not a countdown.
But the warning signs are now more concrete than they were before.
The AMOC is weak. The Gulf Stream appears to be drifting north. The model suggests that such movement can happen before collapse. And scientists now have a way to keep watching.
Whether that warning has arrived early enough is the question nobody can yet answer.
Gary’s love for adventure and preparedness stems from his background as a former Army medic. Having served in remote locations around the world, he knows the importance of being ready for any situation, whether in the wilderness or urban environments. Gary’s practical medical expertise blends with his passion for outdoor survival, making him an expert in both emergency medical care and rugged, off-the-grid living. He writes to equip readers with the skills needed to stay safe and resilient in any scenario.
