According to researchers from ETH Zurich and the University of Miami, some of the largest ocean eddies on Earth are mathematically equivalent to the mysterious black holes of space.
These eddies are so tightly shielded by circular water paths that nothing caught up in them escapes.
The mild winters experienced in Northern Europe are thanks to the Gulf Stream, which makes up part of those ocean currents spanning the globe that impact on the climate. However, our climate is also influenced by huge eddies of over 150 kilometres in diameter that rotate and drift across the ocean. Their number is reportedly on the rise in the Southern Ocean, increasing the northward transport of warm and salty water. Intriguingly, this could moderate the negative impact of melting sea ice in a warming climate.
However, scientists have been unable to quantify this impact so far, because the exact boundaries of these swirling water bodies have remained undetectable. 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. In a paper just published in the Journal of Fluid Mechanics, they develop 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.
No escape from the vortex
Black holes are objects in space with a mass so great that they attract everything that comes within a certain distance of them. Nothing that comes too close can escape, not even light. But at a critical distance, a light beam no longer spirals into the black hole. Rather, it dramatically bends and comes back to its original position, forming a circular orbit. A barrier surface formed by closed light orbits is called a photon sphere in Einstein’s theory of relativity.
Haller and Beron-Vera discovered similar closed barriers around select ocean eddies. In these barriers, fluid particles move around in closed loops – similar to the path of light in a photon sphere. And as in a black hole, nothing can escape from the inside of these loops, not even water.
It is precisely these barriers that help to identify coherent ocean eddies in the vast amount of observational data available. According to Haller, the very fact that such coherent water orbits exist amidst complex ocean currents is surprising.
Eddies as water taxis
Because black-hole-type ocean eddies are stable, they function in the same way as a transportation vehicle – not only for micro-organisms such as plankton or foreign bodies like plastic waste or oil, but also for water with a heat and salt content that can differ from the surrounding water. Haller and Beron-Vera have verified this observation for the Agulhas Rings, a group of ocean eddies that emerge regularly in the Southern Ocean off the southern tip of Africa and transport warm, salty water northwest. The researchers identified seven Agulhas Rings of the black-hole type, which transported the same body of water without leaking for almost a year.
The Latest on: Ocean eddies
- Eddie Branson, Artist, Designs Logo for 2019 Reggae Series on May 19, 2019 at 2:34 pm
Eddie Branson is an incredible artist, expert craftsman, and a lover of reggae. He was born in Baltimore, Maryland and grew up in Ocean City, MD. From a young age, he has been passionate about ... […]
- Fukushima Radiation Is Present in Bering Sea, Researchers Say — But No Cause for Concern on May 14, 2019 at 5:11 pm
Based on their knowledge of ocean currents, passed from generation to generation, St. Lawrence Island residents expected it to happen at some point. Gambell resident Eddie Ungott wasn’t reachable by ... […]
- Eddy currents affect flux of salt more than heat on May 6, 2019 at 7:32 am
Mesoscale eddies, often described as the weather of the ocean, are 3-D structures typically hundreds of kilometers wide and hundreds of meters deep. They are characterized by temperature ... […]
- Google honors Hawaii legend Eddie Aikau on his birthday on May 4, 2019 at 3:27 pm
On what would’ve been Eddie Aikau’s 73rd birthday ... He had a strong love for the ocean as he grew to be a lifeguard on Oahu. He rescued hundreds of people caught in dangerous ocean conditions, ... […]
- Eddie Aikau: Who was the brave surfer and what happened to him? on May 3, 2019 at 11:27 am
and the The Eddie Quiksilver Big Wave Invitational, a surfing competition sponsored by Quiksilver that requires the precondition of ocean swells of a minimum of 20 feet. The competition in honour of ... […]
- Around Ocean City: Soup Bar|Scavenger Hunt|Biking on April 6, 2019 at 6:12 am
Eddie "Chef Ed" McGuarn runs a soup delivery service in Ocean City. It's getting its own restaurant location soon. (Provided by Ed McGuarn) OCEAN CITY, N.J. — Patch reviews this week's top stories ... […]
- Intraseasonal oscillation of deep currents influenced by mesoscale eddies in the Kuroshio Extension Region on March 11, 2019 at 3:42 am
The maximum correlation coefficient between NT in the deep ocean and SLA is also up to 0.7. Positive correlation is observed between deep currents and surface geostrophic current. Furthermore, the ... […]
- Chlorophyll Rings around Ocean Eddies in the North Pacific on February 13, 2019 at 4:00 pm
Chlorophyll rings (CRs) are defined as elevated chlorophyll along eddy peripheries and have been observed in anticyclonic oceanic eddies occasionally. This study presents observations of CRs around ... […]
- Gulf stream eddies as a source of iron on July 3, 2018 at 3:30 pm
and these eddies transport this essential micronutrient to the iron-poor North Atlantic Gyre. Before this discovery, the typical assumption was that this part of the ocean received iron primarily from ... […]
- Great white sharks seem to love warmer ocean waters, not cold, surprising scientists on June 27, 2018 at 7:28 pm
Ocean eddies are not like the whirlpools found around rocks in rivers for example, but tend to be large whirlpools in the ocean that spin clockwise north of the equator. Scientists found, surprisingly ... […]
via Google News and Bing News