Skip to content

12 horrifying facts about black holes in oceans that you need to know

    So you want to know more about black holes in oceans? Then you have come to the right place! In this article I teach you about these underwater black holes and why they are so fascinating. Ready to learn more? Read on…

    Black holes in oceans- what you should know

    You probably will have heard of black holes – those parts of space where gravity has such a pull that even light can’t get out, creating just this gaping smudge of nothingness. These are scary enough as it is, but there’s something that might be even scarier: black holes in oceans. These are much less commonly spoken about, and as such you may know absolutely nothing about them. But if you are interested in learning more, then here are 12 horrifying facts about black holes in oceans that you need to know…

    1. Black holes in oceans can grow to 93 miles in diameter 

    That’s right; one of the biggest black holes found in an ocean measured 93 miles in diameter. And that, of course, is pretty big – in fact, it is bigger than the whole city of Los Angeles. Given that so much of our planet is covered in water, it is scary to think that some of that is made up of these enormous black holes in oceans…

    2. They are commonly known as ocean eddies

    While this might not be such a ‘horrifying’ fact, it is worth knowing as these phenomena aren’t often labelled as black holes per se. So when you’re reading or researching black holes in oceans, you might not come across a lot of information which in itself can be pretty worrying. But if you were to look into an ocean eddy, you would find a lot more information. Below you’ll find the official definition of an ocean eddy from NASA:

    An eddy is a loop of current that is cut off from the main current, or a small, spinning current. They are comparatively small, short-lived circulation patterns in the ocean. Eddies are ocean features that can be easily seen from space by infrared sensors.There are warm-core eddies and cold-core eddies. Warm-core eddies trap and transport a variety of different kinds of animals within them. Cold-core eddies carry greater biomass, but less diversity of species. Cold-core eddies trap nutrient-rich water and transport both nutrients and plankton.

    It is important to note that not ALL ocean eddies are technically black holes. There is a lot of science behind it, but I hope that by the end of this article you’ll have a much better idea of what black holes in oceans are and how they come to be.

    3. Black holes in oceans can be seen from space

    As mentioned in the NASA definition, black holes in oceans can actually be seen from space because they are that big. If that isn’t one of the 12 horrifying facts about black holes in oceans, then I don’t know what is! Scientists up in space use infrared to look down at our planet, and they can spot these giant ocean eddies from all the way up there.

    4. They are caused by surplus energy 

    Black holes in oceans are caused by excess energy. Eddies are found pretty much all over the world, in every ocean, but perhaps the most prominent (and important) are in the Antarctic Ocean, otherwise known as the Southern Ocean. Eddies (or black holes in oceans) here have a really powerful impact on the planet’s climate, providing a connection between the deep ocean and the atmosphere. We can use this ocean to explain how eddies and black holes are actually created. An article in WIRED puts it like this:

    The Southern Ocean circles Antarctica, enabling surface winds to drive it eastward in a continuous loop. The Antarctic Circumpolar Current, as it’s called, has an average or “mean flow,” while buildups of surplus energy erupt into eddies — circular currents tens of miles across that stir the water and, in a feedback process, reinforce the mean flow.

    5. Nothing can escape

    Just as with black holes in space, when it comes to black holes in oceans nothing can escape. People, debris, marine life and even the water itself literally cannot get out of an ocean eddy. Because of the circular water path being so incredibly tight, nothing is able to get past the outline of these strange phenomena. 

    Apparently, the way to tell if an ocean eddy is in fact an ocean black hole is if it has what is known as a ‘coherent boundary’. As you might imagine, figuring this out when you’re looking at a body of water within a body of water is very difficult. But it can be done!

    SciTech Daily published an article saying that George Haller, Professor of Nonlinear Dynamics at ETH Zurich, and Francisco Beron-Vera, Research Professor of Oceanography at the University of Miami, have now come up with a solution to this problem [with] a new mathematical technique to find water-transporting eddies with coherent boundaries.

    The challenge in finding such eddies is to pinpoint coherent water islands in a turbulent ocean. The rotating and drifting fluid motion appears chaotic to the observer both inside and outside an eddy. Haller and Beron-Vera were able to restore order in this chaos by isolating coherent water islands from a sequence of satellite observations. To their surprise, such coherent eddies turned out to be mathematically equivalent to black holes.

    6. Black holes are spreading pollution in the ocean

    Given what scientists know about these ocean eddies, those which are the same as black holes anyway, there is a definite link between them and the spread of pollution within the ocean. When these eddies open up and capture debris, plastic, trash, dead animals, driftwood and so on, they then keep it tightly within themselves before they then spin and drift across the ocean. If they open up again, the debris and anything else they have collected will be deposited in a new area – meaning they are definitely having a negative impact on our oceans in that way.

    But it’s actually not all bad when it comes to ocean eddies’ impact on the ocean and, by extension, the planet. If we refer back to the earlier mentioned WIRED article on the topic of ocean eddies (which you can read here) we come to understand that these circulations conspire to make the Southern Ocean a remarkably efficient absorber of greenhouse gases, which are swallowed at the surface and channeled to the seafloor. And as a driver of global ocean currents, the Southern Ocean bolsters the impact of the other oceans on the climate, too.

    So it looks like black holes in oceans, while being pretty horrifying in general, might actually be a good thing sometimes…

    7. They exist for hours to days at a time

    Next up on the list of 12 horrifying facts about black holes in oceans that you need to know is that they can exist for days at a time. They are not permanent bodies, rather they are generated and will drift before simply dissipating. Some last for just hours, while some last for a good few days. Both are equally scary; those which last for just hours are really difficult to analyze or study. And those which last for a few days… well, nothing within them is safe, so that is obviously where the fear factor comes from in this case.

    8. But some can last for years

    While most of black holes in oceans do only last for hours/days at a time, there are some which last for around 2-3 years. Haller and Beron-Vera actually found 7 eddies known as the Agulhas eddies. According to a collaborative article in a journal called ‘Climate’ they are anticyclonic structures, meaning that their rotation in the Southern Hemisphere is counterclockwise, have high pressure centers, and displace isopycnals downward. Considered the largest mesoscale structures of the world’s oceans, the Agulhas eddies are approximately 300 km in size and 2 km deep (up to 4 km deep) and have lifetimes of 2–3 years.

    It is also said that the Agulhas eddies are recurring – they come back again and again, taking the same path, almost in a similar way to animal migration on land. This cyclical pattern is, of course, fascinating and has been the subject of plenty of research.

    The article goes on to explain that considering that the Agulhas eddies can intensify the CO2 uptake at the sea surface compared to the surrounding waters, more anthropogenic carbon can penetrate into the water column through the mode water formation processes. The propagation of the Agulhas eddies within the South Atlantic Ocean could be one of the key processes responsible for the rapid acidification levels reported for the central waters of this basin – proven by the greater amounts of anthropogenic carbon found inside the eddies than in their surrounding waters.

    You can read the full article here if you are interested in analysing more of the science behind this fascinating phenomenon.

    9. There is a secondary type of black holes in oceans

    While this article has been focusing on the type of black holes in oceans which are mathematically identical to those in space, there is another kind that came before this. The most famous of these is the Black Hole of Andros, located within an island in the Atlantic Ocean. It is an isolated column, 47 metres deep, which has a really interesting scientific makeup. 

    The column was formed by chemical erosion, scientists discovered, and if you go down about 18 metres then there is a thick layer of purple – a toxic bacteria with really high levels of hydrogen sulphide. The shade of purple is so dark that it would be easy to mistake this point as the floor of this ‘hole’. However, there is roughly another 30 metres to go, and anything further down past this point has zero oxygen within it. The purple layer is in fact a boundary, and the water below it has the same properties as the water in the ocean did around 3.5 billion years ago!

    10. They can be killed by the wind

    Although an eddy, or an ocean black hole, isn’t actually a living thing, they can be killed. It’s all part and parcel of the natural way of things; you can read more about it here but essentially, when winds get stronger eddies actually die off. The linked article says that wind destroys ocean eddies by applying stress to the ocean’s surface and slowing eddies’ spin to the point of extinguishing them. Because wind stress hinges on the difference between the speed and direction of wind compared with the speed and direction of the ocean’s surface flow, wind categorically slows eddies rather than quickening them.

    11. We don’t actually know that much about them

    Perhaps the scariest thing about any scientific phenomenon is a lack of knowledge; while I’ve been able to share 12 horrifying facts about black holes oceans, that is not to say that scientists actually know all that much about these eddies and their impact on our oceans and planet. Given that less than 10% of the ocean has been mapped and discovered, it goes without saying that we don’t have as much information as we could about what goes on within the waters of our planet or black holes in oceans.

    It is only within the last 10 years that research into these ocean black holes has been published and become accessible to the masses – particularly due to the aforementioned (and really important) research carried out by Haller and Beron-Vera. They are now well known in fields related to ocean science.

    12. Edgar Allen Poe was the first to talk about black holes in oceans

    Again, this final fact might not be particularly terrifying but it really is interesting! American author Edgar Allen Poe published his novel, A Descent into the Maelstrom, in 1841. The story is of a man recounting his experience being shipwrecked and pulled into a whirlwind. Apparently, this book served as inspiration for Haller Beron-Vera all those years later – they wanted to find the stable belts of foam found around a maelstrom as described by Edgar Allen Poe! This is how they ended up research black holes in oceans in the first place.

    Black holes in oceans- To conclude

    They might seem scary, but black holes in oceans actually aren’t all that bad. If you’ve enjoyed learning about this particular scientific phenomenon, you might enjoy these other blog posts I’ve written…