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DYNAMICAL OCEANOGRAPHY
as in (ii) in that there must exist a sub-layer where lateral friction is important
(Fig. 6.2c). With δ I ≫ max(δ M ,δ S ), the sub-layer has the scale ℓ M
∗ with
(
δ M
ℓ M
∗
)
3 = O(
δ I
ℓ M
∗
)
2 .
(6.28)
If all three effects have the same order of magnitude, the boundary layer structure is more complicated but the cases above cover all interesting and essentially
different cases.
(a)
(b)
(c)
Figure 6.2. Boundary layer structure for three different cases. (a) Munk boundary layer, (b)
Stommel boundary layer with viscous sublayer, and (c) inertial boundary layer with viscous sublayer.