An eddy is defined as "a current at variance with the main current in a stream of liquid or gas, especially one having a rotary or whirling motion." The maelstroms are reportedly bigger than cities and are to water what black holes are to light.
In a paper published by George Haller, a professor at ETH Zurich, and Francisco Beron-Vera of the University of Miami in the August issue of the Journal of Fluid Mechanics researchers claim they were able track and define eddies, a task that had proved impossible thus far.
By studying satellite imagery Haller and Baron-Vera were able to identify seven black-hole types in a group of eddies. They concluded that maelstroms have the same mathematical properties as black holes.
The study adds that eddies "create moving oases for the marine food chain or even impact climate change through their long-range transport of salinity and temperature."