A gyre is a ringlike system of ocean currents. It’s a circular rotation of water, driven by wind and formed by Coriolis force; a major system of surface ocean currents.
There are 5 gyres around the globe:
- the North Atlantic Gyre,
- the South Atlantic Gyre,
- the North Pacific Gyre,
- the South Pacific Gyre
- the Indian Ocean Gyre.
The direction on rotation depends on hemisphere (clockwise in Northern hemisphere, counterclockwise in southern hemisphere).
Gyres have a tendency to draw the pollution released in coastal areas to the ocean. As a result, so called Garbage Patches are formed – mostly made up of the
microbeads and plastic fibers.
Map of ocean currents and gyres. deBlij H.J., Muller P.O. 1976 Physical geography of the global environment.