<p>The length scale associated with molecular viscosity in the ocean is much smaller than typical oceanographic length scales. Zero relative velocity will apply over perhaps a few millimeters. Beyond this, exchanges of momentum are actually achieved by turbulence, not by molecular viscosity. This is the reason why Ekman theory is built on the principle of conservation of momentum (action-reaction between ocean and atmosphere) and effectively discards the condition that relative velocity at the interface should be zero. </p>

CC BY-SA 3.0
2017-08-24T10:12:17.947Z
2017-08-24T10:12:17.947Z
Michel Crucifix
<p>Is it not the Ekman Transport, or wind drag of the surface water,  a violation of the Physical evidence of zero relative velocity at any boundary, in viscous flow?</p>

<oceanography>
Ekman Transport
luis blas Cabrera
# Ekman Transport

(Asked by: username_0 on 2017-08-12)

Is it not the Ekman Transport, or wind drag of the surface water, a violation of the Physical evidence of zero relative velocity at any boundary, in viscous flow?

**Tags:** oceanography


---

## 1 answers

### Answer by username_1 on 2017-08-24. Score: 2

The length scale associated with molecular viscosity in the ocean is much smaller than typical oceanographic length scales. Zero relative velocity will apply over perhaps a few millimeters. Beyond this, exchanges of momentum are actually achieved by turbulence, not by molecular viscosity. This is the reason why Ekman theory is built on the principle of conservation of momentum (action-reaction between ocean and atmosphere) and effectively discards the condition that relative velocity at the interface should be zero.


---

