Ocean currents are movements of water from one location to another in the ocean. They are driven by a range of sources, including:

• Wind: Winds drive currents that are at or near the oceans surface. Near coastal areas, winds tend to drive currents on a localized scale and can result in phenomena like coastal upwelling. On a more global scale, in the open ocean, winds drive currents that circulate water for thousands of miles throughout the ocean basins.

• Density differences: Currents may also be caused by density differences in water masses due to temperature (thermo) and salinity (haline) variations via a process known as thermohaline circulation. These currents move water masses through the deep ocean, taking nutrients, oxygen, and heat with them.

• Tides: Tides create a current in the oceans, which are strongest near the shore, and in bays and estuaries along the coast. These are called "tidal currents." Tidal currents change in a very regular pattern and can be predicted for future dates. In some locations, strong tidal currents can travel at speeds of eight knots or more.

• Gravity: Gravity can also drive ocean currents. For example, the gravitational pull of the Moon and the Sun causes tides, which in turn can create currents.

• Earths rotation: The rotation of the Earth plays a role in ocean currents through the Coriolis effect. This effect causes currents in the Northern Hemisphere to curve to the right and currents in the Southern Hemisphere to curve to the left.

The patterns of ocean currents are determined by a combination of these factors, as well as the position of landforms that interact with the currents. Ocean currents play an important role in determining the climates of coastal regions and in transferring heat from Earth’s equatorial areas to the poles.