“The Day After Tomorrow,” titled movie released in 2004 which alerts global leaders about the fast climate change, seems to be happening true. After a recently published study found that the Atlantic Meridional Overturning Circulation (AMOC), which is a major factor that is responsible for the movement of warm water from equatorial tropics up to Europe and the North Atlantic, is slowing down due to climate change.
In the movie, it was shown that AMOC halted completely due to which an ice age started overnight. The speed and power of that cold stream are hyperbolized in the film, but AMOC is the reality. And if it ever stopped completely in reality (which is likely to happen by 2100), much of North America and Europe could be plunged into freezing temperatures (ice age) for hundreds if not thousands of years, claim scientists (via Insider).
In a paper published last week, scientist Niklas Boers pointed out that the AMOC is reaching the tipping point. If melting of polar ice (water) reaches the ocean, the present system will undergo an “abrupt weakening,” and destabilization.
The UN’s Intergovernmental Panel on Climate Change (IPCC) presented a report which also suggests that AMOC is likely to be debilitated by the end of this century. This debilitation will result in a fall in the temperature of Europe and the cooling effect will increase more towards the north.
The US East Coast will face a rise in sea level, central and west Africa will face drought because those parts also come under AMOC’s circulation. AMOC’s fast movement brings wet and warm climate in Europe. Scientists imagined it as a conveyor belt.
When warm water reaches the UK, it cools down and sinks to the bottom of the Labrador and Nordic Seas. After that cold water takes a U-turn and moves along Antarctica’s Southern Ocean. But the weakness in this circulation does not allow warm tropical waters to move up and results in north Atlantic cools.
The AMOC’s speed is based on a delicate balance of salt and fresh water. Because of the high density of salty water, it sinks. AMOC’s salty surface water slowly became lighter due to the melting of Greenland’s ice sheet and glaciers and resulted in fewer chances of drowning and further resulting in a halt to the circulation’s flow.
Francesco Muschitiello, a geographer specializing in paleoclimatology at the University of Cambridge told Insider,
“The most efficient and easiest way to disrupt the climate system is the shutdown of AMOC, 95% of the time when we talk about rapid climate change, it’s associated with AMOC.”
Boers says that any cooling related to Atlantic Meridional Overturning Circulation would not look like “The Day After Tomorrow”, either it may take some decades, and also North America would not get as cold as suggested in the movie. Probably a few hundred years are required for AMOC to re-strengthen.
As per the IPCC report, AMOC will likely go through an abrupt collapse around 2100. The collapse was probably caused by an unexpected additional melted ice from the Greenland Ice Sheet. A study from 2019 found that the ice sheet was melting six times faster than it was 40 years ago.
It is believed that the last time the AMOC stopped was around 11,700 years ago. And if the Atlantic Meridional Overturning Circulation were to halt down completely one more time then the only way to undo it would be to reverse the global temperature trend and get back to the earlier industrial conditions.