• Bell, G. I., 1990: Interaction between vortices and waves in a model of geophysical flow. Phys. Fluids, 2, 575586.

  • Bell, G. I., and L. G. Pratt, 1992: The interaction of an eddy with an unstable jet. J. Phys. Oceanogr., 22, 12291244.

  • Chapman, D. C., and K. H. Brink, 1987: Shelf and slope circulation induced by fluctuating offshore forcing. J. Geophys. Res., 92, 11 74111 759.

    • Search Google Scholar
    • Export Citation
  • Dinniman, M. S., J. M. Klinck, and W. O. Smith Jr., 2011: A model study of Circumpolar Deep Water on the West Antarctic Peninsula and Ross Sea continental shelves. Deep-Sea Res. II, in press, doi:10.1016/j.dsr2.2010.11.013.

    • Search Google Scholar
    • Export Citation
  • Dritschel, D. G., 1988: Contour surgery: A topological reconnection scheme for extended integrations using contour dynamics. J. Comput. Phys., 77, 240266.

    • Search Google Scholar
    • Export Citation
  • Frolov, S. A., G. G. Sutyrin, G. D. Rowe, and L. M. Rothstein, 2004: Loop Current eddy interaction with the western boundary in the Gulf of Mexico. J. Phys. Oceanogr., 34, 22232237.

    • Search Google Scholar
    • Export Citation
  • Garfield, N., and D. L. Evans, 1987: Shelf water entrainment by Gulf Stream warm-core rings. J. Geophys. Res., 92, 13 00313 012.

  • Hofmann, E. E., J. M. Klick, D. P. Costa, K. L. Daly, J. J. Torres, and W. R. Fraser, 2002: U.S. Southern Ocean Global Ocean Ecosystems Dynamics program. Oceanography, 15, 6474.

    • Search Google Scholar
    • Export Citation
  • Klinck, J. M., 1998: Heat and salt changes on the continental shelf west of the Antarctic Peninsula between January 1993 and January 1994. J. Geophys. Res., 103, 76177636.

    • Search Google Scholar
    • Export Citation
  • Klinck, J. M., E. E. Hofmann, R. C. Beardsley, B. Salihoglu, and S. Howard, 2004: Water-mass properties and circulation on the west Antarctic Peninsula continental shelf in austral fall and winter 2001. Deep-Sea Res. II, 51, 19251946.

    • Search Google Scholar
    • Export Citation
  • Louis, J. P., and P. C. Smith, 1982: The development of the barotropic radiation field of an eddy on a slope. J. Phys. Oceanogr., 12, 5673.

    • Search Google Scholar
    • Export Citation
  • Moffat, C., B. Owens, and R. C. Beardsley, 2009: On the characteristics of Circumpolar Deep Water intrusions to the west Antarctic Peninsula Continental Shelf. J. Geophys. Res., 114, C05017, doi:10.1029/2008JC004955.

    • Search Google Scholar
    • Export Citation
  • Orsi, A. H., T. Whitworth, and W. D. Nowlin, 1995: On the meridional extent and fronts of the Antarctic Circumpolar Current. Deep-Sea Res., 42, 641673.

    • Search Google Scholar
    • Export Citation
  • Prezelin, J. R., E. E. Hofmann, C. Mengelt, and J. M. Klinck, 2000: The linkage between Upper Circumpolar Deep Water (UCDW) and phytoplankton assemblages on the west Antarctic Peninsula continental shelf. J. Mar. Res., 58, 165202.

    • Search Google Scholar
    • Export Citation
  • Smith, D. A., E. E. Hofmann, J. M. Klinck, and C. M. Lascara, 1999: Hydrography and circulation of the west Antarctic Peninsula continental shelf. Deep-Sea Res., 46, 951984.

    • Search Google Scholar
    • Export Citation
  • Smith, D. C., and J. J. O’Brien, 1983: The interaction of a two-layer isolated mesoscale eddy with bottom topography. J. Phys. Oceanogr., 13, 16811697.

    • Search Google Scholar
    • Export Citation
  • Stern, M. E., 1991: Entrainment of an eddy at the edge of a jet. J. Fluid Mech., 228, 343360.

  • Stern, M. E., and G. R. Flierl, 1987: On the interaction of a vortex with a shear flow. J. Geophys. Res., 92, 10 73310 744.

  • Wang, X., 1992: Interaction of an eddy with a continental slope. Ph.D. thesis, Massachusetts Institute of Technology/Woods Hole Oceanographic Institution, 216 pp.

    • Search Google Scholar
    • Export Citation
  • White, A. J., and N. R. McDonald, 2004: The motion of a point vortex near large-amplitude topography in a two-layer fluid. J. Phys. Oceanogr., 34, 28082824.

    • Search Google Scholar
    • Export Citation
  • Zhang, Y., 2009: Slope/shelf circulation and cross-slope/shelf transport out of a bay driven by eddies from the open ocean. Ph.D. thesis, Massachusetts Institute of Technology/Woods Hole Oceanographic Institution, 222 pp.

    • Search Google Scholar
    • Export Citation
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Shelf Circulation and Cross-Shelf Transport out of a Bay Driven by Eddies from an Open-Ocean Current. Part I: Interaction between a Barotropic Vortex and a Steplike Topography

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  • 1 Massachusetts Institute of Technology, Cambridge, Massachusetts
  • | 2 Woods Hole Oceanographic Institution, Woods Hole, Massachusetts
  • | 3 Massachusetts Institute of Technology, Cambridge, Massachusetts
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Abstract

This paper examines interaction between a barotropic point vortex and a steplike topography with a bay-shaped shelf. The interaction is governed by two mechanisms: propagation of topographic Rossby waves and advection by the forcing vortex. Topographic waves are supported by the potential vorticity (PV) jump across the topography and propagate along the step only in one direction, having higher PV on the right. Near one side boundary of the bay, which is in the wave propagation direction and has a narrow shelf, waves are blocked by the boundary, inducing strong out-of-bay transport in the form of detached crests. The wave–boundary interaction as well as out-of-bay transport is strengthened as the minimum shelf width is decreased. The two control mechanisms are related differently in anticyclone- and cyclone-induced interactions. In anticyclone-induced interactions, the PV front deformations are moved in opposite directions by the point vortex and topographic waves; a topographic cyclone forms out of the balance between the two opposing mechanisms and is advected by the forcing vortex into the deep ocean. In cyclone-induced interactions, the PV front deformations are moved in the same direction by the two mechanisms; a topographic cyclone forms out of the wave–boundary interaction but is confined to the coast. Therefore, anticyclonic vortices are more capable of driving water off the topography. The anticyclone-induced transport is enhanced for smaller vortex–step distance or smaller topography when the vortex advection is relatively strong compared to the wave propagation mechanism.

Corresponding author address: Yu Zhang, Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 54-1421, Cambridge, MA 02139. E-mail: sophiezy@mit.edu

Abstract

This paper examines interaction between a barotropic point vortex and a steplike topography with a bay-shaped shelf. The interaction is governed by two mechanisms: propagation of topographic Rossby waves and advection by the forcing vortex. Topographic waves are supported by the potential vorticity (PV) jump across the topography and propagate along the step only in one direction, having higher PV on the right. Near one side boundary of the bay, which is in the wave propagation direction and has a narrow shelf, waves are blocked by the boundary, inducing strong out-of-bay transport in the form of detached crests. The wave–boundary interaction as well as out-of-bay transport is strengthened as the minimum shelf width is decreased. The two control mechanisms are related differently in anticyclone- and cyclone-induced interactions. In anticyclone-induced interactions, the PV front deformations are moved in opposite directions by the point vortex and topographic waves; a topographic cyclone forms out of the balance between the two opposing mechanisms and is advected by the forcing vortex into the deep ocean. In cyclone-induced interactions, the PV front deformations are moved in the same direction by the two mechanisms; a topographic cyclone forms out of the wave–boundary interaction but is confined to the coast. Therefore, anticyclonic vortices are more capable of driving water off the topography. The anticyclone-induced transport is enhanced for smaller vortex–step distance or smaller topography when the vortex advection is relatively strong compared to the wave propagation mechanism.

Corresponding author address: Yu Zhang, Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 54-1421, Cambridge, MA 02139. E-mail: sophiezy@mit.edu
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