A new study indicates that the collapse of the Atlantic Meridional Overturning Circulation — which would be a catastrophic climate event — can no longer be considered an unlikely scenario.
What’s happening?
Scientists have demonstrated through new analysis that the collapse of a crucial system of ocean currents due to human-caused pollution is far more likely than previously thought. According to The Guardian, the new study shows that “the tipping point that makes an AMOC shutdown inevitable is likely to be passed within a few decades,” though “the collapse itself may not happen until 50 to 100 years later.”
Researchers from the Potsdam Institute for Climate Impact Research, the Royal Netherlands Meteorological Institute, and the National Oceanography Centre in the United Kingdom published the study in the journal Environmental Research Letters in August. It concludes, according to a release from the Potsdam Institute, that unless heat-trapping pollution is meaningfully reduced, the AMOC “could shut down after the year 2100.”
That’s the year before which previous models suggested the system would not likely collapse. However, projecting a bit further into the future may tell a different story, “[showing] very worrying results,” as lead author Sybren Drijfhout said in a statement.
”The deep overturning in the northern Atlantic slows drastically by 2100 and completely shuts off thereafter in all high-emission scenarios, and even in some intermediate and low-emission scenarios,” Drijfhout continued. “That shows the shutdown risk is more serious than many people realize.”
Co-author Stefan Rahmstorf told The Guardian that he previously described the possibility that the AMOC would collapse due to rising global temperatures at around 10 percent — now he said he might describe it as closer to 25 percent.
Want to go solar but not sure who to trust? EnergySage has your back with free and transparent quotes from fully vetted providers that can help you save as much as $10k on installation.
To get started, just answer a few questions about your home — no phone number required. Within a day or two, EnergySage will email you the best local options for your needs, and their expert advisers can help you compare quotes and pick a winner.
He also warned that the point of no return is imminent without drastic action.
“We found that the tipping point where the shutdown becomes inevitable is probably in the next 10 to 20 years or so,” Rahmstorf said. “That is quite a shocking finding as well and why we have to act really fast in cutting down emissions.”
Meanwhile, Jonathan Baker at the Met Office Hadley Centre in the UK told the outlet that the new results should be “treated with caution,” explaining that “the sample size is small, so more simulations [beyond 2100] are needed to better quantify the risk.”
Why is the possibility of an AMOC collapse so concerning?
The AMOC essentially acts as a very slow conveyor belt circulating warm water north and cool water south. As the National Oceanic and Atmospheric Administration has explained, the whole process takes place over a thousand years — that’s how long it takes one parcel of water to complete the cycle.
If the AMOC were to collapse entirely, the consequences would be felt globally.
For example, Western Europe enjoys a relatively mild climate because of the AMOC. If the system were to collapse, Europe would experience significantly colder winter temperatures and much drier summers, per the UK’s National Centre for Atmospheric Science.
Worldwide, the rain belt would shift, drastically reducing crop yields and exacerbating extreme weather events.
Coastal communities would also be under threat from rising sea levels.
What’s being done to prevent the collapse?
While deeply concerning, this modeling is still in its early stages, and the collapse of the AMOC is unlikely to occur before the end of this century. With the tipping point potentially 10 to 20 years away, there are actions that individuals, communities, and governments around the world can take now to address the underlying issue of rising global temperatures.
Baker, who said more research was needed to validate the new findings, also told The Guardian the stakes are high.
“Even if a collapse is unlikely, a major weakening is expected, and that alone could have serious impacts on Europe’s climate in the decades to come,” he said. “But the future of the Atlantic circulation is still in our hands.”
Adopting clean, renewable energy at the household, neighborhood, and national scales is the primary mitigation that experts have advised to roll back the heat-trapping blanket of human-caused pollution from the planet. Transitioning from fossil fuels to more sustainable energy sources has other benefits too — such as strengthening the public’s resilience to the outages of traditional power grids that can be exacerbated by the extreme weather an AMOC collapse may worsen.
Join our free newsletter for good news and useful tips, and don’t miss this cool list of easy ways to help yourself while helping the planet.
