A simple predictive model for the structure of the oceanic pycnocline

Science

Volumn 283, Issue 5410, 1999, Pages 2077-2079

  Gnanadesikan, Anand ^a  

^a PRINCETON UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

DIFFUSION; OCEANIC CIRCULATION; PYCNOCLINE; UPWELLING;

ARTICLE; GRAVITY; PREDICTION; PRIORITY JOURNAL; SEA; SURFACE PROPERTY; VISCOSITY; WATER FLOW;

EID: 0033605628     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.283.5410.2077     Document Type: Article

References (30)

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2. F. Bryan, J. Phys. Oceanogr. 17, 970 (1987); R. A. DeSzoeke, ibid. 25, 918 (1995).
3. S. Levitus, A Climatological Atlas of the World Ocean (NOAA Prof. Pap. 13, U.S. Government Printing Office, Washington, DC, 1992).
4. See A. Macdonald and C. Wunsch, Nature 382, 436 (1996); C. Wunsch, D. Hu, B. Grant, J. Phys. Oceanogr. 13, 725 (1983).
5. See A. Macdonald and C. Wunsch, Nature 382, 436 (1996); C. Wunsch, D. Hu, B. Grant, J. Phys. Oceanogr. 13, 725 (1983).
6. H. M. Stommel [Tellus 13, 224 (1961)] was the first to use this approximation. See D. G. Wright and T. Stocker, J. Phys. Oceanogr. 21, 1713 (1991); R. X. Huang, J. R. Luyten, H. M. Stommel, ibid. 22, 231 (1992); and S. M. Griffies and E. Tziperman, J. Climate 8, 2440 (1995) for more recent examples.
7. H. M. Stommel [Tellus 13, 224 (1961)] was the first to use this approximation. See D. G. Wright and T. Stocker, J. Phys. Oceanogr. 21, 1713 (1991); R. X. Huang, J. R. Luyten, H. M. Stommel, ibid. 22, 231 (1992); and S. M. Griffies and E. Tziperman, J. Climate 8, 2440 (1995) for more recent examples.
8. H. M. Stommel [Tellus 13, 224 (1961)] was the first to use this approximation. See D. G. Wright and T. Stocker, J. Phys. Oceanogr. 21, 1713 (1991); R. X. Huang, J. R. Luyten, H. M. Stommel, ibid. 22, 231 (1992); and S. M. Griffies and E. Tziperman, J. Climate 8, 2440 (1995) for more recent examples.
9. H. M. Stommel [Tellus 13, 224 (1961)] was the first to use this approximation. See D. G. Wright and T. Stocker, J. Phys. Oceanogr. 21, 1713 (1991); R. X. Huang, J. R. Luyten, H. M. Stommel, ibid. 22, 231 (1992); and S. M. Griffies and E. Tziperman, J. Climate 8, 2440 (1995) for more recent examples.
10. W. Munk, J. Meteorol. 7, 79 (1950).
11. D. G. Wright, T. F. Stocker, and D. Mercer [J. Phys. Oceanogr. 28, 791 (1998)] provide a comprehensive discussion of this issue in zonally averaged climate models. T. M. C. Hughes and A. Weaver [ibid. 24, 619 (1994)] provide evidence for a relation between meridional pressure gradient and overturning strength in a GCM. An alternative explanation to the frictional explanation is to suppose that some portion of the eastward geostrophic transport associated with the pressure gradient is converted to overturning, as supposed by Bryan [in (1)].
12. D. G. Wright, T. F. Stocker, and D. Mercer [J. Phys. Oceanogr. 28, 791 (1998)] provide a comprehensive discussion of this issue in zonally averaged climate models. T. M. C. Hughes and A. Weaver [ibid. 24, 619 (1994)] provide evidence for a relation between meridional pressure gradient and overturning strength in a GCM. An alternative explanation to the frictional explanation is to suppose that some portion of the eastward geostrophic transport associated with the pressure gradient is converted to overturning, as supposed by Bryan [in (1)].
13. The flow will be off to the left of the wind stress, because the Coriolis force acting on this velocity will balance the surface stress; see J. F. Price, R. A. Weller, R. R. Schudlich, Science 238, 1534 (1987) for observations of such flow.
14. P. R. Gent and J. C. McWilliams, J. Phys. Oceanogr. 20, 150 (1990); P. Gent, J. Willebrand, T. J. McDougall, J. C. McWilliams, ibid. 26, 463 (1995); and G. Danabasoglu, J. C. McWilliams, P. R. Gent, Science 264, 1123 (1994) document the effect of this parameterization on the global temperature and salinity structure.
15. P. R. Gent and J. C. McWilliams, J. Phys. Oceanogr. 20, 150 (1990); P. Gent, J. Willebrand, T. J. McDougall, J. C. McWilliams, ibid. 26, 463 (1995); and G. Danabasoglu, J. C. McWilliams, P. R. Gent, Science 264, 1123 (1994) document the effect of this parameterization on the global temperature and salinity structure.
16. P. R. Gent and J. C. McWilliams, J. Phys. Oceanogr. 20, 150 (1990); P. Gent, J. Willebrand, T. J. McDougall, J. C. McWilliams, ibid. 26, 463 (1995); and G. Danabasoglu, J. C. McWilliams, P. R. Gent, Science 264, 1123 (1994) document the effect of this parameterization on the global temperature and salinity structure.
17. W. Munk, Deep-Sea Res. 13, 707 (1966).
18. 1) in the relatively quiet subtropical gyre.
19. 1) in the relatively quiet subtropical gyre.
20. 1) in the relatively quiet subtropical gyre.
21. 2 is the potential density referenced to 2000 m. Pyc-nocline depths are computed from 50°W to 70°W and 40°S to 40°N in the Atlantic Basin.
22. See, for example, W. J. Schmitz and M. S. McCartney, Rev. Geophys. 33, 151 (1993).
23. J. Ledwell, A. Watson, C. S. Law, Nature 364, 701 (1993).
24. J. R. Toggweiler and B. Samuels, in The Global Carbon Cycle, M. Heimann, Ed. (Springer-Verlag, Berlin, 1993), pp. 303-331.
25. W. Munk and C. Wunsch [Deep-Sea Res. Part I Oceanogr. Res. Pap. 45, 1977 (1998)] discuss this issue in detail.
26. The model used here is the GFDL Modular Ocean Model Version 3.0 documented in R. C. Pacanowski and S. M. Griffies, GFDL Tech. Rep. 3 (Geophysical Fluid Dynamics Laboratory, Princeton, NJ, 1998). The grid spacing and bottom topography for this model are identical to those used in Toggweiler and Samuels (17). The surface winds are taken from S. Hellermann and M. Rosenstein, J. Phys. Oceanogr. 13, 1093 (1982). Surface salinities are restored toward the climatological observations of Levitus (2), whereas surface temperatures are restored toward the data set that was used to drive the Atmospheric Model Intercomparison Project (AMIP) runs as described in W. L Gates, Bull. Am. Meteorol. Soc. 73, 1962 (1992).
27. The model used here is the GFDL Modular Ocean Model Version 3.0 documented in R. C. Pacanowski and S. M. Griffies, GFDL Tech. Rep. 3 (Geophysical Fluid Dynamics Laboratory, Princeton, NJ, 1998). The grid spacing and bottom topography for this model are identical to those used in Toggweiler and Samuels (17). The surface winds are taken from S. Hellermann and M. Rosenstein, J. Phys. Oceanogr. 13, 1093 (1982). Surface salinities are restored toward the climatological observations of Levitus (2), whereas surface temperatures are restored toward the data set that was used to drive the Atmospheric Model Intercomparison Project (AMIP) runs as described in W. L Gates, Bull. Am. Meteorol. Soc. 73, 1962 (1992).
28. The model used here is the GFDL Modular Ocean Model Version 3.0 documented in R. C. Pacanowski and S. M. Griffies, GFDL Tech. Rep. 3 (Geophysical Fluid Dynamics Laboratory, Princeton, NJ, 1998). The grid spacing and bottom topography for this model are identical to those used in Toggweiler and Samuels (17). The surface winds are taken from S. Hellermann and M. Rosenstein, J. Phys. Oceanogr. 13, 1093 (1982). Surface salinities are restored toward the climatological observations of Levitus (2), whereas surface temperatures are restored toward the data set that was used to drive the Atmospheric Model Intercomparison Project (AMIP) runs as described in W. L Gates, Bull. Am. Meteorol. Soc. 73, 1962 (1992).
29. J. R. Toggweiler and B. Samuels, J. Phys. Oceanogr. 28, 1832 (1998).
30. This work was supported by the Carbon Modeling Consortium, NOAA grant NA56GP0439, and by the Geophysical Fluid Dynamics Lab. I thank A. Gnanadesikan and T. Hughes for extensive help with the text and model runs, and H. Bjornsson, R. Toggweiler, K. Bryan, and R. Hallberg for useful discussions. This paper is dedicated to the memory of Tertia Hughes.