A scientist is worried about an ocean system that is starting to weaken as a result of climate change.
The Atlantic Ocean's Atlantic Meridional Overturning Circulation (AMOC) helps regulate temperature and weather systems across Europe and North America.
The AMOC creates the Gulf Stream, which moves warm water from the Indian Ocean, across to the Gulf of Mexico, then over to European continent, where it cools around Greenland and sinks to the ocean floor before slinking back down the eastern South American coastline.
This conveyer belt-like system is absolutely vital to life in that part of the world and one expert is concerned the system is starting to falter.
Climate scientist Niklas Boers has recently published a paper that says the AMOC could shut off abruptly.
If that were to happen, it could plunge the two sides of the Atlantic Ocean into freezing temperatures.
In his paper, published in Nature, he wrote: "Observations and recently suggested fingerprints of AMOC variability indicate a gradual weakening during the last decades, but estimates of the critical transition point remain uncertain.
"Significant early-warning signals are found in eight independent AMOC indices, based on observational sea-surface temperature and salinity data from across the Atlantic Ocean basin.
"These results reveal spatially consistent empirical evidence that, in the course of the last century, the AMOC may have evolved from relatively stable conditions to a point close to a critical transition."
As Greenland's ice sheet continues to melt due to rising temperatures, more fresh water is being dumped at that turnaround point in the AMOC system.
This is preventing the warm salt water from sinking and is causing a kink in the system.
Funnily enough, the last time the AMOC switched off was when a fresh water lake burst and spilled into the ocean. This is believed to have caused Earth's most recent ice age, which happened around 11,700 years ago.
If any of this is sounding familiar to you then you'd be correct because this is essentially how the movie The Day After Tomorrow started.
Dennis Quaid played climatologist Jack Hall, who tried to warn politicians that climate change was affecting the AMOC system and everyone could die unless they moved south.
Of course, no one listened and sure enough North America and Europe were plunged into a frozen wasteland.
Hollywood overdramatised how quickly the effects of the AMOC shutting off would kick in, with New York City hit by a freak tsunami that gets frozen solid after just a few days.
Niklas Boers said it would actually take a few decades before the two continents would experience freezing temperatures, and that North America 'won't get as cold as the movie suggests'.
But he said it would happen eventually if the AMOC goes through its critical transition.
Featured Image Credit: 20th Century Fox