Black holes don't only exist in the cold distance of deep space, they also exist right here on Earth, swirling in the oceans. Scientists from ETH Zurich and the University of Miami have discovered that many large ocean eddies on Earth are mathematically equivalent to the black holes of space, meaning nothing trapped by them can escape, according to

The discovery sounds scarier than the reality. Researchers have long known that massive eddies exist in our oceans and that they can have a large impact on the climate. But these eddies exist on an immense scale, often spanning some 150 kilometers (about 93 miles) in diameter. If you swam into one, you probably wouldn't know it. Though they act like vortices, the sheer size of them makes it difficult to identify their exact boundaries, even for scientists.

But a new mathematical technique introduced by researchers could shed some light on these mysterious ocean maelstroms. The technique looks for similar mathematical structures in the ocean that are also known to occur at the edges of black holes.

"The boundaries of water-carrying eddies satisfy the same type of differential equations that the area surrounding black holes do in general relativity," said George Haller, one of the researchers in the study.

Using satellite observations, the researchers were not only able to identify the boundaries of several of these eddies, but they confirmed that the eddies were mathematically equivalent to black holes.

These ocean vortices are so tight that they act like a container for the water trapped inside them. Water temperatures and salt content within the eddies can be different from the surrounding ocean. As they drift across the sea, they act as transports for micro-organisms like plankton, or even for human trash such as plastic waste or oil.

One interesting consequence of these black holes of the sea is that they may be increasing the northward transport of warm and salty water from the Southern Ocean, also known as the Antarctic Ocean. This is important because it might be helping to slow the melt of sea ice in the Southern Hemisphere, which could counteract some of the negative effects of global warming.

Now that researchers have a way of identifying the boundaries of these swirling eddies, they can begin to study exactly how the vortices might impact our changing climate.

The following video, supplied by New Scientist, showcases how some of these black hole-like eddies have been studied moving across the ocean. A particularly large vortex can be seen spiraling across the Gulf of Mexico.

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