Driving forces of currents
There are many factors that determine the speed of a current, as well as its route. Winds have the most important influence on the flow of currents, but tides, precipitation, evaporation rates, shape of the ocean floor, and inflow from rivers and adjacent seas are also important. The waters of the north Pacific Ocean move in a general east to west direction, in response to the predominant trade winds. The general westerly movement of the Pacific waters around the equator forms the North and South Equatorial Currents, belts of water moving approximately parallel to the equator, which lie about 15° latitude on either side of it. Between these two currents, the Equatorial Countercurrent flows to the east.