• Bitz, C. M., and W. H. Lipscomb, 1999: An energy-conserving thermodynamic model of sea ice. J. Geophys. Res., 104 , 1566915677.

  • Bitz, C. M., M. M. Holland, M. Eby, and A. J. Weaver, 2001: Simulating the ice-thickness distribution in a coupled climate model. J. Geophys. Res., 106 , 24412463.

    • Search Google Scholar
    • Export Citation
  • Bonan, G. B., K. W. Oleson, M. Vertenstein, S. Levis, X. Zeng, Y. Dai, R. E. Dickinson, and Z-L. Yang, 2002: The land surface climatology of the community land model coupled to the NCAR community climate model. J. Climate, 15 , 31233149.

    • Search Google Scholar
    • Export Citation
  • Boville, B. A., and P. R. Gent, 1998: The NCAR Climate System Model, version one. J. Climate, 11 , 11151130.

  • Briegleb, B. P., E. C. Hunke, C. M. Bitz, W. H. Lipscomb, M. M. Holland, J. L. Schramm, and R. E. Moritz, 2004: The sea ice simulation of the Community Climate System Model, version two. NCAR Tech. Note NCAR/TN-45+STR, 34 pp.

  • Cai, W., and P. G. Baines, 2001: Forcing of the Antarctic Circumpolar Wave by El Niño–Southern Oscillation teleconnections. J. Geophys. Res., 106 , 90199038.

    • Search Google Scholar
    • Export Citation
  • Cai, W., P. G. Baines, and H. B. Gordon, 1999: Southern mid- to high-latitude variability, a zonal wavenumber-3 pattern, and the Antarctic Circumpolar Wave in the CSIRO coupled model. J. Climate, 12 , 30873104.

    • Search Google Scholar
    • Export Citation
  • Carleton, A. M., 1988: Sea ice atmosphere signal of the Southern Oscillation in the Weddell Sea, Antarctica. J. Climate, 1 , 379388.

  • Christoph, M., T. P. Barnett, and E. Roeckner, 1998: The Antarctic Circumpolar Wave in a coupled atmosphere–ocean GCM. J. Climate, 11 , 16591672.

    • Search Google Scholar
    • Export Citation
  • Connolley, W. M., 2003: Long-term variation of the Antarctic Circumpoler Wave. J. Geophys. Res., 108 .8076, doi:10.1029/2000JC00380.

  • Gent, P. R., and J. C. McWilliams, 1990: Isopycnal mixing in ocean circulation models. J. Phys. Oceanogr., 20 , 150155.

  • Gent, P. R., W. G. Large, and F. O. Bryan, 2001: What sets the mean transport through Drake Passage? J. Geophys. Res., 106 , 26932712.

    • Search Google Scholar
    • Export Citation
  • Gloersen, P., and W. B. White, 2001: Reestablishing the circumpolar wave in sea ice around Antarctica from one winter to the next. J. Geophys. Res., 106 , 43914395.

    • Search Google Scholar
    • Export Citation
  • Goosse, H., and T. Fichefet, 1999: Importance of ice–ocean interactions for the global ocean circulation: A model study. J. Geophys. Res., 104 , 2333723355.

    • Search Google Scholar
    • Export Citation
  • Haarsma, R. J., F. M. Selten, and J. M. Opsteegh, 2000: On the mechanism of the Antarctic Circumpolar Wave. J. Climate, 13 , 14611480.

    • Search Google Scholar
    • Export Citation
  • Hall, A., and M. Visbeck, 2002: Synchronous variability in the Southern Hemisphere atmosphere, sea ice, and ocean resulting from the annular mode. J. Climate, 15 , 30433057.

    • Search Google Scholar
    • Export Citation
  • Hunke, E. C., 2001: Viscous–plastic sea ice dynamics with the EVP model: Linearization issues. J. Comput. Phys., 170 , (1),. 1838.

  • Hunke, E. C., and J. K. Dukowicz, 1997: An elastic–viscous–plastic model for sea ice dynamics. J. Phys. Oceanogr., 27 , 18491867.

  • Hunke, E. C., and J. K. Dukowicz, 2002: The elastic–viscous–plastic sea ice dynamics model in general orthogonal curvilinear coordinates on a sphere—Incorporation of metric terms. Mon. Wea. Rev., 130 , 18481865.

    • Search Google Scholar
    • Export Citation
  • Jacobs, G. A., and J. L. Mitchell, 1996: Ocean circulation variations associated with the Antarctic Circumpolar Wave. Geophys. Res. Lett., 23 , 29472950.

    • Search Google Scholar
    • Export Citation
  • Karoly, D. J., 1989: Southern Hemisphere circulation features associated with El Niño–Southern Oscillation events. J. Climate, 2 , 12391252.

    • Search Google Scholar
    • Export Citation
  • Kidson, J. W., and J. A. Renwick, 2002: The Southern Hemisphere evolution of ENSO during 1981–1999. J. Climate, 15 , 847863.

  • Kiehl, J. T., and P. R. Gent, 2004: The Community Climate System Model, version two. J. Climate, 17 , 36663682.

  • Kiehl, J. T., J. J. Hack, G. B. Bonan, B. A. Boville, B. P. Briegleb, D. L. Williamson, and P. J. Rasch, 1996: Description of the NCAR Community Climate Model (CCM3). NCAR Tech. Note NCAR/TN-420+STR, 152 pp.

  • Kwok, R., and J. C. Comiso, 2002: Southern Ocean climate and sea ice anomalies associated with the Southern Oscillation. J. Climate, 15 , 487501.

    • Search Google Scholar
    • Export Citation
  • Large, W. G., J. C. McWilliams, and S. C. Doney, 1994: Oceanic vertical mixing: A review and a model with a nonlocal boundary layer parameterization. Rev. Geophys., 32 , 363403.

    • Search Google Scholar
    • Export Citation
  • Ledley, T. S., and Z. Huang, 1997: A possible ENSO signal in the Ross Sea. Geophys. Res. Lett., 24 , 32533256.

  • Lipscomb, W. H., 2001: Remapping the thickness distribution in sea ice models. J. Geophys. Res., 106 , 1398914000.

  • Liu, J., J. A. Curry, and D. G. Martinson, 2004: Interpretation of recent Antarctic sea ice variability. Geophys. Res. Lett., 31 .L02205, doi:10.1029/2003GL018732.

    • Search Google Scholar
    • Export Citation
  • North, G. R., T. L. Bell, R. F. Cahalan, and F. J. Moeng, 1982: Sampling errors in the estimation of empirical orthogonal functions. Mon. Wea. Rev., 110 , 699706.

    • Search Google Scholar
    • Export Citation
  • Peterson, R. G., and W. B. White, 1998: Slow oceanic teleconnections linking the Antarctic Circumpolar Wave with the tropical El Niño–Southern Oscillation. J. Geophys. Res., 103 , 2457324583.

    • Search Google Scholar
    • Export Citation
  • Raphael, M. N., 2003: Impact of observed sea-ice concentration on the Southern Hemisphere extratropical atmospheric circulation in summer. J. Geophys. Res., 108 .4687, doi:10.1029/2002JD003308.

    • Search Google Scholar
    • Export Citation
  • Rothrock, D. A., 1975: The energetics of the plastic deformation of pack ice by ridging. J. Geophys. Res., 80 , 45144519.

  • Saenko, O. A., A. J. Weaver, and J. M. Gregory, 2003: On the link between the two modes of the ocean thermohaline circulation and the formation of global-scale water masses. J. Climate, 16 , 27972801.

    • Search Google Scholar
    • Export Citation
  • Simmonds, I., and T. H. Jacka, 1995: Relationships between the interannual variability of Antarctic sea ice and the Southern Oscillation. J. Climate, 8 , 637647.

    • Search Google Scholar
    • Export Citation
  • Smith, R., and P. Gent, Eds., cited. 2002: Reference manual for the Parallel Ocean Program ocean component of the Community Climate System Model (CCSM2.0). [Available online at http://www.ccsm.ucar.edu/models.].

  • Stossel, A., S. J. Kim, and S. S. Drijfhout, 1998: The impact of Southern Ocean sea ice in a global ocean model. J. Phys. Oceanogr., 28 , 19992018.

    • Search Google Scholar
    • Export Citation
  • Thompson, D. W., and J. M. Wallace, 2000: Annual modes in extratropical circulation. Part I: Month-to-month variability. J. Climate, 13 , 10001016.

    • Search Google Scholar
    • Export Citation
  • Thompson, D. W., and S. Solomon, 2002: Interpretation of recent Southern Hemisphere climate change. Science, 296 , 895899.

  • Thorndike, A. S., D. S. Rothrock, G. A. Maykut, and R. Colony, 1975: Thickness distribution of sea ice. J. Geophys. Res., 80 , 45014513.

    • Search Google Scholar
    • Export Citation
  • Trathan, P. N., and E. J. Murphy, 2003: Sea surface temperature anomalies near South Georgia: Relationships with the Pacific El Niño regions. J. Geophys. Res., 108 .8075, doi:10.1029/2000JC000299.

    • Search Google Scholar
    • Export Citation
  • Trenberth, K. E., and J. M. Caron, 2000: The Southern Oscillation revisited: Sea level pressures, surface temperatures, and precipitation. J. Climate, 13 , 43584365.

    • Search Google Scholar
    • Export Citation
  • White, W. B., and R. G. Peterson, 1996: An Antarctic circumpolar wave in surface pressure, wind, temperature and sea ice extent. Nature, 380 , 699702.

    • Search Google Scholar
    • Export Citation
  • Yuan, X., and D. G. Martinson, 2000: Antarctic sea ice extent variability and its global connectivity. J. Climate, 13 , 16971717.

  • Yuan, X., and D. G. Martinson, 2001: The Antarctic Dipole and its predictability. Geophys. Res. Lett., 28 , 36093612.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 1 1 1
PDF Downloads 2 2 2

Mechanisms Forcing an Antarctic Dipole in Simulated Sea Ice and Surface Ocean Conditions

View More View Less
  • 1 National Center for Atmospheric Research,* Boulder, Colorado
  • | 2 Polar Science Center, Applied Physics Laboratory, Seattle, Washington
  • | 3 T-3 Fluid Dynamics Group, Los Alamos National Laboratory, Los Alamos, New Mexico
Restricted access

Abstract

The mechanisms forcing variability in Southern Ocean sea ice and sea surface temperature from 600 years of a control climate coupled model integration are discussed. As in the observations, the leading mode of simulated variability exhibits a dipole pattern with positive anomalies in the Pacific sector associated with negative anomalies in the Atlantic. It is found that in the Pacific ocean circulation changes associated with variable wind forcing modify the ocean heat flux convergence and sea ice transport, resulting in sea surface temperature and sea ice anomalies. The Pacific ice and ocean anomalies persist over a number of years due to reductions in ocean shortwave absorption reinforcing the initial anomalies. In the Atlantic sector, no single process dominates in forcing the anomalies. Instead there are contributions from changing ocean and sea ice circulation and surface heat fluxes. While the absorbed solar radiation in the Atlantic is modified by the changing surface albedo, the anomalies are much shorter-lived than in the Pacific because the ocean circulation transports them northward, removing them from ice formation regions. Sea ice and ocean anomalies associated with the El Niño–Southern Oscillation and the Southern Annular Mode both exhibit a dipole pattern and contribute to the leading mode of ice and ocean variability.

Corresponding author address: Dr. Marika Holland, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307. Email: mholland@ucar.edu

Abstract

The mechanisms forcing variability in Southern Ocean sea ice and sea surface temperature from 600 years of a control climate coupled model integration are discussed. As in the observations, the leading mode of simulated variability exhibits a dipole pattern with positive anomalies in the Pacific sector associated with negative anomalies in the Atlantic. It is found that in the Pacific ocean circulation changes associated with variable wind forcing modify the ocean heat flux convergence and sea ice transport, resulting in sea surface temperature and sea ice anomalies. The Pacific ice and ocean anomalies persist over a number of years due to reductions in ocean shortwave absorption reinforcing the initial anomalies. In the Atlantic sector, no single process dominates in forcing the anomalies. Instead there are contributions from changing ocean and sea ice circulation and surface heat fluxes. While the absorbed solar radiation in the Atlantic is modified by the changing surface albedo, the anomalies are much shorter-lived than in the Pacific because the ocean circulation transports them northward, removing them from ice formation regions. Sea ice and ocean anomalies associated with the El Niño–Southern Oscillation and the Southern Annular Mode both exhibit a dipole pattern and contribute to the leading mode of ice and ocean variability.

Corresponding author address: Dr. Marika Holland, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307. Email: mholland@ucar.edu

Save