How are warm-core Gulf Stream rings different from cold-core rings?

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Map of the North Atlantic Ocean showing major ocean currents, with warm currents like the Gulf Stream and North Atlantic Drift highlighted in pink and cold currents in blue. Arrows indicate current directions and relative speeds, connecting the eastern coasts of North America, the western coasts of Europe and Africa, and the Arctic region. — Gulf Stream Major warm and cold currents of the North Atlantic Ocean.

Gulf Stream rings are eddy structures that develop from meanders in the current east of Cape Hatteras. They are categorized based on their formation, rotation, and composition:

Warm-core rings: These form when meanders pinch off on the continental slope side of the Gulf Stream. They consist of waters from the Gulf Stream and the Sargasso Sea, rotate clockwise, and typically measure 100 to 300 km in diameter. They generally move westward and are reabsorbed into the Gulf Stream after approximately six months. About five of these rings form annually.
Cold-core rings: These form when meanders pinch off to the south of the Gulf Stream. They are composed of a mixture of Gulf Stream and continental slope waters, rotate counterclockwise, and are generally larger, with diameters of 200 to 300 km. They typically move southwestward into the Sargasso Sea, have longer lifetimes of one to two years, and are more frequent, with about 10 forming each year.1