The surface currents are affected by the Coriolis Effect which is a result of how the Earth spins on it axis. The Coriolis Effect causes the winds to move the first 400 meters of water in the ocean and this creates the movement of the water by the surface currents.
The wind blows on the surface currents of the ocean, creating large circular patterns called gyres. The gyres are a by-product of the Coriolis Effect which causes the clockwise movement of ocean waters in the Northern Hemisphere and the counterclockwise movement of surface currents in the Southern Hemisphere. Gyres flow in opposite directions on oceans near the North and South Poles.
Surface currents move the ocean's water in regular patterns that vary in depth and size. The shape of the ocean floor determines the type of surface currents that form; some currents have a deep and narrow formation while others can be shallow and wide. Currents can change in speed and depth over a period of time. Large currents have the ability to move big bodies of water between oceans and rivers.
