The Ekman spiral effect is the tendency for ocean currents to propagate at an angle to the surface winds. It derives its name from the Swedish oceanographer Vagn Ekman .
The effect is a consequence of the Coriolis effect. The driving force for ocean currents is surface winds. In the northern hemisphere, the surface currents are deflected to the right of the wind direction by coriolis forces, and progressivly deeper layers are deflected further to the right. In the deep ocean, the bottom currents can end up flowing in the oposite direction to the surface currents, due to this effect.
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