Surface currents in the ocean are caused by a combination of factors, including wind, the Coriolis effect, and the shape of the ocean basins. Wind-driven surface currents are generated by global wind systems that are fueled by energy from the Sun. The patterns of surface currents are determined by wind direction, the Coriolis effect from the Earths rotation, and the position of landforms that interact with the currents. In addition to these regular influences, natural disasters such as huge storms and underwater earthquakes can trigger ocean currents.

Surface currents can flow for thousands of kilometers and can reach depths of hundreds of meters. They are extremely important because they distribute heat around the planet and are a major factor influencing climate around the globe.