• Chang, K-I., , M. Ghil, , K. Ide, , and C-C. A. Lai, 2001: Transition to aperiodic variability in a wind-driven double-gyre circulation model. J. Phys. Oceanogr., 31 , 12601286.

    • Search Google Scholar
    • Export Citation
  • Chen, F., , and M. Ghil, 1995: Interdecadal variability of the thermohaline circulation and high-latitude surface fluxes. J. Phys. Oceanogr., 25 , 25472568.

    • Search Google Scholar
    • Export Citation
  • Delworth, T. L., , and M. E. Mann, 2000: Observed and simulated multidecadal variability in the Northern Hemisphere. Climate Dyn., 16 , 661676.

    • Search Google Scholar
    • Export Citation
  • Delworth, T. L., , S. Manabe, , and R. J. Stouffer, 1993: Interdecadal variations of the thermohaline circulation in a coupled ocean–atmosphere model. J. Climate, 6 , 19932011.

    • Search Google Scholar
    • Export Citation
  • De Niet, A. C., , F. W. Wubs, , A. Terwisscha van Scheltinga, , and H. A. Dijkstra, 2007: A tailored solver for bifurcation analysis of ocean-climate models. J. Comput. Phys., in press.

    • Search Google Scholar
    • Export Citation
  • Dijkstra, H. A., 2005: Nonlinear Physical Oceanography: A Dynamical Systems Approach to the Large Scale Ocean Circulation and El Niño. 2d ed. Dordrecht, 532 pp.

    • Search Google Scholar
    • Export Citation
  • Dijkstra, H. A., 2006: The interaction of SST modes in the North Atlantic. J. Phys. Oceanogr., 36 , 286299.

  • Greatbatch, R. J., , and S. Zhang, 1995: An interdecadal oscillation in an idealized ocean basin forced by constant heat flux. J. Climate, 8 , 8291.

    • Search Google Scholar
    • Export Citation
  • Haney, R. L., 1971: Surface thermal boundary condition for ocean circulation models. J. Phys. Oceanogr., 1 , 241248.

  • Huck, T., , A. Colin de Verdiére, , and A. J. Weaver, 1999: Interdecadal variability of the thermohaline circulation in box-ocean models forced by fixed surface fluxes. J. Phys. Oceanogr., 29 , 865892.

    • Search Google Scholar
    • Export Citation
  • Jin, F-F., , and J. D. Neelin, 1993: Modes of interannual tropical ocean–atmosphere interaction—A unified view. Part I: Numerical results. J. Atmos. Sci., 50 , 34773503.

    • Search Google Scholar
    • Export Citation
  • Keller, H. B., 1977: Numerical solution of bifurcation and nonlinear eigenvalue problems. Applications of Bifurcation Theory, P. H. Rabinowitz, Ed., Academic Press, 359–385.

    • Search Google Scholar
    • Export Citation
  • Kravtsov, S., , and M. Ghil, 2004: Interdecadal variability in a hybrid coupled ocean–atmosphere–sea ice model. J. Phys. Oceanogr., 34 , 17561775.

    • Search Google Scholar
    • Export Citation
  • Pedlosky, J., 1987: Geophysical Fluid Dynamics. 2d ed. Springer-Verlag, 710 pp.

  • Sheremet, V. A., , G. R. Ierley, , and V. M. Kamenkovich, 1997: Eigenanalysis of the two-dimensional wind-driven ocean circulation problem. J. Mar. Res., 55 , 5792.

    • Search Google Scholar
    • Export Citation
  • Simonnet, E., , and H. A. Dijkstra, 2002: Spontaneous generation of low-frequency modes of variability in the wind-driven ocean circulation. J. Phys. Oceanogr., 32 , 17471762.

    • Search Google Scholar
    • Export Citation
  • Sleijpen, G. L. G., , and H. A. Van der Vorst, 1996: A Jacobi-Davidson iteration method for linear eigenvalue problems. SIAM J. Matrix Anal. Appl., 17 , 410425.

    • Search Google Scholar
    • Export Citation
  • Te Raa, L. A., , and H. A. Dijkstra, 2002: Instability of the thermohaline ocean circulation on interdecadal time scales. J. Phys. Oceanogr., 32 , 138160.

    • Search Google Scholar
    • Export Citation
  • Te Raa, L. A., , J. Gerrits, , and H. A. Dijkstra, 2004: Identification of the mechanism of interdecadal variability in the North Atlantic Ocean. J. Phys. Oceanogr., 34 , 27922807.

    • Search Google Scholar
    • Export Citation
  • Toggweiler, J. R., , and B. Samuels, 1995: Effect of Drake Passage on the global thermohaline circulation. Deep-Sea Res., 42 , 477500.

  • von der Heydt, A., , and H. A. Dijkstra, 2007: Localized modes of multidecadal variability. Part I: Cross-equatorial transport and interbasin exchange. J. Phys. Oceanogr., 37 , 24012414.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 48 48 21
PDF Downloads 1 1 0

Localization of Multidecadal Variability. Part II: Spectral Origin of Multidecadal Modes

View More View Less
  • 1 Institute for Marine and Atmospheric Research Utrecht, Department of Physics and Astronomy, Utrecht University, Utrecht, Netherlands
© Get Permissions Rent on DeepDyve
Restricted access

Abstract

In a companion paper, the authors have shown that in an idealized Atlantic–Pacific Ocean configuration with a conveyor-type overturning circulation, localized multidecadal variability occurs in the Atlantic. Results suggest that the multidecadal variability originates from the instability of the three-dimensional thermohaline circulation and that the physics of the spatial patterns of the SST anomalies can be understood from a study of an Atlantic-only configuration. Specific internal (multidecadal) modes, which obtain a positive growth factor depending on the background thermohaline flow, are associated with the instability. In this paper, the spectral origin of these internal modes is studied using eigensolution continuation techniques. As in the single-hemispheric case, multidecadal modes arise through mergers of so-called SST modes. In the double-hemispheric case studied here, there actually are two types of multidecadal modes that lead to oscillatory behavior. Depending on the background conditions, one of these oscillatory flows is preferred.

Corresponding author address: Henk Dijkstra, Institute for Marine and Atmospheric Research Utrecht, Department of Physics and Astronomy, Utrecht University, 3584CC Utrecht, Netherlands. Email: dijkstra@phys.uu.nl

Abstract

In a companion paper, the authors have shown that in an idealized Atlantic–Pacific Ocean configuration with a conveyor-type overturning circulation, localized multidecadal variability occurs in the Atlantic. Results suggest that the multidecadal variability originates from the instability of the three-dimensional thermohaline circulation and that the physics of the spatial patterns of the SST anomalies can be understood from a study of an Atlantic-only configuration. Specific internal (multidecadal) modes, which obtain a positive growth factor depending on the background thermohaline flow, are associated with the instability. In this paper, the spectral origin of these internal modes is studied using eigensolution continuation techniques. As in the single-hemispheric case, multidecadal modes arise through mergers of so-called SST modes. In the double-hemispheric case studied here, there actually are two types of multidecadal modes that lead to oscillatory behavior. Depending on the background conditions, one of these oscillatory flows is preferred.

Corresponding author address: Henk Dijkstra, Institute for Marine and Atmospheric Research Utrecht, Department of Physics and Astronomy, Utrecht University, 3584CC Utrecht, Netherlands. Email: dijkstra@phys.uu.nl

Save