The wind: holds the ocean water and pushes it forward.
Coriolis effect: caused by the Earth’s rotation and effects the flow of the fluid to bend. The path of any object set in motion above a rotating surface will curve in relation to objects on that surface. This apparent deflection is the Coriolis Effect.
In the Northern hemisphere a fluid turns to right hemisphere it turns to left. Therefore, as in the picture, the ocean currents in the North Pacific flow west along the equator, moving northeast along the East Asian continent and the Japanese island, forming a reflux along the west coast of North America. In the South Pacific, reflux appears in the counterclockwise direction.
Causes of Gyre
Tropical: occurs near the equator. Main force for the tropical gyre is the blow of wind.
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Subtropical: Form between the polar and equatorial regions of Earth. Most ocean gyres are subtropical.
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Subpolar: near the planet’s pole. An area of low atmospheric pressure.
Types of Gyre
As mentioned, gyre is consistently moving and that’s the reason why garbage can is flowing for a long period.
However, the surrounded area is actually stationary which means there is no external force to move the garbage. As a result, garbage usually accumulates at the center of ocean gyres and stays for many years.
If we try to just scoop up the debris, it takes too much time and could disrupt marine life as well. Also, we need to take into consideration the sunken debris.