A gyre is the circular rotation of water within a basin that is driven by the wind. There are three different cells of wind that blow across each hemisphere of the Earth. In the Northern Hemisphere wind blows from east to west at the equator, pushing surface water to the northwest. As it rises and makes its way to about 30 degrees latitude, the wind shifts directions and blows from west to east, changing the path of the surface water to turn back down towards the southeast. This continuing pattern results in a slow clockwise rotation of water across the entire Pacific Ocean. This same phenomenon repeats itself in all 5 gyres found around the globe with the direction of rotation depending on the hemisphere: the North Atlantic gyre, the South Atlantic Gyre, the North Pacific Gyre, the South Pacific Gyre, and the Indian Ocean Gyre.
The constant circulation combined with the Coriolis effect has a tendency to draw water towards the center of the gyre, almost like the rotation in your toilet, almost. Essentially pulling garbage and anything floating in the water towards the middle. All of the garbage simply floats around breaking into smaller and smaller pieces, but never goes away. However, gyres also extremely important to help spread eggs and larvae around the Ocean. Certain species rely on the currents from gyres to help spread their young into new water so that they do not end up competing for space in the future. Pretty smart!
Check out National Geographic’s page for information on gyres and more: http://education.nationalgeographic.com/education/encyclopedia/ocean-gyre/?ar_a=1
