We thank Dr. Vassil Roussenov for supplying a version of the float advection code. The work was supported by the AMT program supported by the UK NERC Consortium grant (NER/O/S/2001/01245). We also thank two anonymous reviewers for their constructive comments.
Andrews, D. G., , and M. E. McIntyre, 1976: Planetary waves in horizontal and vertical shear: The generalized Eliassen–Palm relation and the mean zonal acceleration. J. Atmos. Sci., 33 , 2031–2048.
Bleck, R., , and L. T. Smith, 1990: A wind-driven isopycnic coordinate model of the north and equatorial Atlantic Ocean. 1. Model development and supporting experiments. J. Geophys. Res., 95 , C3,. 3273–3285.
Boudra, D. B., , and E. P. Chassignet, 1988: Dynamics of Agulhas retroflection and ring formation in a numerical model. Part I: The vorticity balance. J. Phys. Oceanogr., 18 , 280–303.
Danabasoglu, G., , J. C. McWilliams, , and P. R. Gent, 1994: The role of mesoscale tracer transport in the global ocean circulation. Science, 264 , 1123–1126.
Drijfhout, S. S., , and W. Hazeleger, 2001: Eddy mixing of potential vorticity versus thickness in an isopycnic ocean model. J. Phys. Oceanogr., 31 , 481–505.
Gent, P. R., , J. Willebrand, , T. J. McDougal, , and J. C. McWilliams, 1995: Parameterizing eddy-induced tracer transports in ocean circulation models. J. Phys. Oceanogr., 25 , 463–474.
Gill, A. E., , J. S. A. Green, , and A. J. Simmons, 1974: Energy partition in the large-scale ocean circulation and the production of mid-ocean eddies. Deep-Sea Res., 21 , 499–528.
Greatbatch, R. J., 1998: Exploring the relationship between eddy-induced transport velocity, vertical momentum transfer, and the isopycnal flux of potential vorticity. J. Phys. Oceanogr., 28 , 422–432.
Illari, L., , and J. C. Marshall, 1983: On the interpretation of eddy fluxes during a blocking episode. J. Atmos. Sci., 40 , 2232–2242.
Karsten, R. H., , and J. C. Marshall, 2002: Constructing the residual circulation of the ACC from observations. J. Phys. Oceanogr., 32 , 3315–3327.
Lee, M-M., , D. P. Marshall, , and R. G. Williams, 1997: On the eddy transfer of tracers: Diffusive or advective? J. Mar. Res., 55 , 1–24.
Lindzen, R. S., , and B. Farrell, 1980: A simple approximate result for the maximum growth rate of baroclinic instabilities. J. Atmos. Sci., 37 , 1648–1654.
Marshall, D. P., , R. G. Williams, , and M-M. Lee, 1999: The relation between eddy-induced transport and isopycnic gradients of potential vorticity. J. Phys. Oceanogr., 29 , 1571–1578.
McDowell, S., , P. B. Rhines, , and T. Keffer, 1982: North Atlantic potential vorticity and its relation to the general circulation. J. Phys. Oceanogr., 12 , 1417–1436.
Panetta, R. L., 1993: Zonal jets in wide baroclinically unstable regions—Persistence and scale selection. J. Atmos. Sci., 50 , 2073–2106.
Plumb, R. A., , and J. D. Mahlman, 1987: The zonally averaged transport characteristics of the GFDL general circulation/transport model. J. Atmos. Sci., 44 , 298–327.
Rhines, P. B., , and W. R. Young, 1982b: A theory of the wind-driven circulation. I. Mid-ocean gyres. J. Mar. Res., 40 , (Suppl.),. 559–596.
Roberts, M. J., , and D. M. Marshall, 2000: On the validity of downgradient eddy closures in ocean models. J. Geophys. Res., 105 , 28613–28627.
Treguier, A. M., , I. M. Held, , and V. D. Larichev, 1997: Parameterization of quasigeostrophic eddies in primitive equation ocean models. J. Phys. Oceanogr., 27 , 567–580.
Visbeck, M., , J. Marshall, , T. Haine, , and M. Spall, 1997: Specification of eddy transfer coefficients in coarse-resolution ocean circulation models. J. Phys. Oceanogr., 27 , 381–402.
Wilson, C., , and R. G. Williams, 2004: Why are eddy fluxes of potential vorticity difficult to parameterize? J. Phys. Oceanogr., 34 , 142–155.