Chapter 11 - Wind Driven Ocean
11.5 Important Concepts
- The theory for wind-driven, geostrophic currents was first outlined in
a series of papers by Sverdrup, Stommel, and Munk between 1947 and 1951.
- They showed that realistic currents can be calculated only if the Coriolis
parameter varies with latitude.
- 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.
- Stommel showed that western boundary currents are required for flow to
circulate around an ocean basin when the Coriolis parameter varies with latitude.
- 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.
- 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
- 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.