Current

A CURRENT IS the ordered movement of a fluid in time. A number of different physical factors including tides, landslides, winds, horizontal pressure gradients, and changes in water density can put water into motion. Of these factors, regional winds, horizontal pressure gradients, and density changes can drive currents on basin-wide or global spatial scale. These moving water parcels, in turn, transport not only matter, but also heat. Therefore, changes in the strength or location of currents that cover sufficiently large distances can alter global climate.

Wind-driven currents are produced when winds transfer energy into the surface layer of the water column. Once the water is set into motion, the Coriolis force acts upon it, and the surface layer is deflected 45 degrees to the right of ...