Across Indian 15. Atlantic Return Let's see what happens if we combine our wind data with the layering in the upper ocean and the rotation of the earth. The motions of the water within the layers of seawater, below the wind, do not follow the winde, but are deflected from the direction of the wind, because of the rotation of the Earth. Remember we discussed the motion of a moving body on a rotating plant, the Coriolis effect, in exercise 11 . Moreover, the amount of deflection would increases with water depth as the momentum in one layer is transferred to the layer below, so on and so forth.
Water is shown in light blue.
If we combine these views, we can see the effect in three-dimensions with the Red arrow showing the wind direction The spiralling nature of the motion in the water is known as the Ekman spiral. The layer in the ocean where this spiral motion takes places is called the Ekman layer. The transport of ocean water at 90 o to the wind direction is known as Ekman transport.