Tides Tide Activity Currents J ust like waves, oceans currents are always moving about.
Winds affect the ocean's surface only.
Both winds are a result of warm air from the tropics moving to the poles and incorporating the rotation of Earth into their movement. In the Northern Hemisphere, they move clockwise. In the Southern Hemisphere, they move counter-clockwise. Differences in temperature between the cold waters of the poles and the warm waters near the equator cause currents. Cold-water currents occur as the cold water at the poles sinks and slowly moves toward the equator.