Ekman transport

Ekman transport is a name given to the natural process by which each layer of water in the ocean drags with it the layer beneath. Thus the movement of each layer of water is affected by the movement of the layer above. Each successive layer feels the force of the surface layer a little less, similar to the way sound is transported through air particles. With each wave-length transport the wave becomes weaker and weaker, which is why someone at a distance has more difficulty hearing you than someone close to you.

It is closely related to the Ekman spiral, where winds blowing up and down coastal regions cause a seaward flow of surface water (perpendicular to the flow of wind), which creates the upwelling of deep nutrient rich sea water. This has the effect of creating good fishing regions along coasts where this phenomenon occurs.