Is this really serious? Scientists have sounded the alarm that “Europe’s central heating” faces full-scale climate breakdown. But some say it is just one of many possible environmental tipping points.
The growing belief in a new ice age
Is this really serious? Scientists have sounded the alarm that "Europe's central heating" faces full-scale climate breakdown. But some say it is just one of many possible environmental tipping points.
The Thames has frozen over. Brave commuters wrapped up tight in layers of thermal clothing brace themselves against the arctic gale. Big Ben has been stopped dead by ice, the clock permanently showing at one second to midnight.
Some scientists think these apocalypticReferring to the end of the world, or the collapse of civilisation. scenes could be our reality in just a few years. This might be surprising to you: for years now, we have been hearing that climate change will bring hotter temperatures. But a growing number of scientists now think that temperatures could start to drop dramatically in northern Europe within this century.
This is because of the Amoc, which stands for the Atlantic meridional overturning circulation. The Amoc is one of our planet's largest systems of heat transport, bringing heat through ocean currents into the North Atlantic.
It has been described as "Europe's central heating". Currents bring warm surface water from the tropicsThe region between the tropics of Cancer and Capricorn. to the north, where they release heat in the subpolarA climate zone that is found in the northern hemisphere, south of the polar climate, and is characterised by severely cold winters and short, cool summers. Atlantic. The water cools, sinks and then returns south as a cold current.1 You might imagine it as a conveyor belt.
But some scientists say that we have been receiving indications for around 70 years that the Amoc has been slowing due to global warming. They say that they have identified a "cold blob" over the North Atlantic - the only place in the world that has got cooler, rather than warmer, as climate change has progressed.
Some believe that this is because of reduced heat from the Amoc, indicating that currents have been weakening. If they ever stopped circulating altogether, scientists agree that we would suffer a planet-wide, existentialRelating to the state of human existence. Existential dread can refer to grappling with your own experiences of responsibility and death. catastrophe.
It would not be the first time that the Amoc has collapsed. The most recent time was during the last ice age, one of the greatest climate upheavals in the history of the planet, around 12,900 years ago.
A modern collapse would see North Atlantic sea levels rising by around half a metre. The temperature in some European cities would drop by more than 10C. The tropical rainfall belt would shift to the south, causing widespread droughts and floods.
In 2023, a sibling team of scientists from Denmark studied sea surface temperatures in the North Atlantic and concluded that the Amoc could pass its tipping pointThe point at which a series of small changes or incidents becomes significant enough to cause a larger, more important change. and collapse at any time between 2025 and 2095.2 An open letter from 2024 signed by 44 experts warned that the risk of collapse has been "greatly underestimated".
Not everyone is in agreement. A different team of scientists concluded in 2025 that the Amoc had not declined over the past 60 years.3 The Intergovernmental Panel on Climate Change (IPCC) expressed "low confidence" that the Amoc had declined in the last century, and "medium confidence" that it would not collapse before 2100.4
The only consensus is that Amoc will, at some point, collapse. But many believe this will come after more serious climate tipping points, like the collapse of the ice sheets and Amazon rainforest dieback, at which point all will already be lost.5
This might not reassure you. But perhaps more alarmingly, experts say that the science is too imprecise for anybody to come up with a fully reliable time frame for Amoc collapse. It could be tomorrow, or it could be in a century. Either way, if we do not clean up our climate act, we could be in for a frosty future.
Is this really serious?
Yes: The risk is huge and grows every day. As seas warm and ice melts from global warming, it gets harder for salty water to sink in northern Europe and make way for warmer currents from the Equator, so currents slow down further. Every day brings Amoc collapse closer.
No: Amoc collapse would be serious indeed, but luckily it is not happening. Plenty of scientists have concluded that currents have not weakened over the past few decades. It is simply fear-mongering and detracts from more important issues.
Or... It does not matter how serious Amoc collapse is. Even if there is only a 5% chance that it will happen in the next 50 years, we should still act to prevent such a catastrophic event. Would you eat a cake that had a 5% chance of poisoning you?
Apocalyptic - Referring to the end of the world, or the collapse of civilisation.
Tropics - The region between the tropics of Cancer and Capricorn.
Subpolar - A climate zone that is found in the northern hemisphere, south of the polar climate, and is characterised by severely cold winters and short, cool summers.
Existential - Relating to the state of human existence. Existential dread can refer to grappling with your own experiences of responsibility and death.
Tipping point - The point at which a series of small changes or incidents becomes significant enough to cause a larger, more important change.
The growing belief in a new ice age

Glossary
Apocalyptic - Referring to the end of the world, or the collapse of civilisation.
Tropics - The region between the tropics of Cancer and Capricorn.
Subpolar - A climate zone that is found in the northern hemisphere, south of the polar climate, and is characterised by severely cold winters and short, cool summers.
Existential - Relating to the state of human existence. Existential dread can refer to grappling with your own experiences of responsibility and death.
Tipping point - The point at which a series of small changes or incidents becomes significant enough to cause a larger, more important change.