Chapter 11 - Wind Driven Ocean Circulation

11.5 Important Concepts

1. The theory for wind-driven, geostrophic currents was first outlined in a series of papers by Sverdrup, Stommel, and Munk between 1947 and 1951.



2. They showed that realistic currents can be calculated only if the Coriolis parameter varies with latitude.



3. Sverdrup showed that the curl of the wind stress drives a northward mass transport, and that this can be used to calculate currents in the ocean away from western boundary currents.



4. Stommel showed that western boundary currents are required for flow to circulate around an ocean basin when the Coriolis parameter varies with latitude.



5. Munk showed how to combine the two solutions to calculate the wind-driven geostrophic circulation in an ocean basin. In all cases, the current is driven by the curl of the wind stress.



6. The observed circulation in the ocean is very turbulent. many years of observations may need to be averaged together to obtain a stable map of the mean flow.



7. The Gulf Stream is a region of baroclinic instability in which turbulence accelerates the stream. This creates a Gulf Stream recirculation. Transports in the recirculation region are much larger than transports calculated from the Sverdrup-Munk theory.

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