• Allen, S., 1996: Topographically generated, subinertial flows within a finite length canyon. J. Phys. Oceanogr, 26 , 16081632.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Arakawa, A., and Lamb V. R. , 1977: Computational design of the basic dynamical processes of the UCLA general circulation model. Methods of Computational Physics, J. Chang, Ed., Vol. 17, Academic Press, 173–265.

    • Search Google Scholar
    • Export Citation
  • Asselin, R., 1972: Frequency filter for time integrations. Mon. Wea. Rev, 100 , 487490.

  • Bogden, P. S., Malanotte-Rizzoli P. , and Signell R. , 1996: Open-ocean boundary conditions from interior data: Local and remote forcing of Massachusetts Bay. J. Geophys. Res, 101 , (C3),. 64876500.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bormans, M., and Garrett C. , 1989: A simple criterion for gyre formation by the surface outflow from a strait, with application to the Alboran Sea. J. Geophys. Res, 94 , 1263712644.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Boyer, D. L., and Davies P. , 2000: Laboratory studies of orographic effects in rotating and stratified flows. Annu. Rev. Fluid Mech, 32 , 165202.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Boyer, D. L., Zhang X. , and Pérenne N. , 2000: Laboratory observations of rotating, stratified flow in the vicinity of a submarine canyon. Dyn. Atmos. Oceans, 31 , 4772.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Briggs, W. L., 1987: A Multigrid Tutorial. Society for Industrial and Applied Mathematics, 90 pp.

  • Dalziel, S. B., 1992: Decay of rotating turbulence: Some particle tracking experiments. Appl. Sci. Res, 49 , 217244.

  • Dukowicz, J., and Smith R. D. , 1994: Implicit free surface method for the Bryan–Cox–Semtner ocean model. J. Geophys. Res, 99 , (C4),. 79918014.

  • Freeland, H., and Denman K. , 1982: A topographically controlled upwelling center off southern Vancouver Island. J. Mar. Res, 40 , 10691093.

    • Search Google Scholar
    • Export Citation
  • Haidvogel, D. B., and Beckman A. , 1998: Numerical modeling of the coastal ocean. The Global Coastal Ocean, Vol. 10, The Sea—Ideas and Observations on Progress in the Study of the Seas, K. H. Brink and A. R. Robinson, Eds., John Wiley and Sons, 457–482.

    • Search Google Scholar
    • Export Citation
  • Harlow, F. H., and Welch J. E. , 1965: Numerical calculation of time-dependent viscous incompressible flow of fluid with free surface. Phys. Fluids, 8 , 21822198.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hickey, B. M., 1997: The response of a steep-sided, narrow canyon to time-variable wind forcing. J. Phys. Oceanogr, 27 , 697726.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kliem, N., and Pietrzak J. D. , 1999: On the pressure gradient error in sigma coordinate ocean models: A comparison with a laboratory model. J. Geophys. Res, 104 , (C12),. 2978129799.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Klinck, J. M., 1996: Circulation near submarine canyons: A modeling study. J. Geophys. Res, 101 , (C1),. 12111223.

  • McClimans, T. A., Pietrzak J. D. , Huess V. , Kliem N. , Nilsen J. H. , and Johannessen B. O. , 2000: Laboratory and numerical simulation of the Skaggerrak circulation. Contin. Shelf Res, 20 , 941974.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pedlosky, J., Whitehead J. A. , and Veitch G. , 1997: Thermally driven motions in a rotating stratified fluid: Theory and experiment. J. Fluid Mech, 339 , 391411.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pérenne, N., Verron J. , Renouard D. , Boyer D. L. , and Zhang X. , 1997: Rectified barotropic flow over a submarine canyon. J. Phys. Oceanogr, 27 , 18681893.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pérenne, N., Haidvogel D. B. , and Boyer D. L. , 2001: Laboratory–numerical model comparisons of flow over a coastal canyon. J. Atmos. Oceanic Technol, 18 , 235255.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sanson, L. Z., and van Heijst G. J. F. , 2000: Interaction of barotropic vortices with coastal topography: Laboratory experiments and numerical simulations. J. Phys. Oceanogr, 30 , 21412162.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • She, J., and Klinck J. M. , 2000: Flow near submarine canyons driven by constant upwelling winds. J. Geophys. Res, 105 , 2867128694.

  • Smolarkiewicz, P., and Clark T. L. , 1986: The multidimensional positive definite advection transport algorithm: Further development and applications. J. Comput. Phys, 67 , 396438.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • UNESCO, 1981: Practical salinity scale 1978 and the international equation of state of seawater. UNESCO Tech. Papers in Marine Science, No. 36, 13–21.

    • Search Google Scholar
    • Export Citation
  • Wang, J., and Ikeda M. , 1997: Inertial stability and phase error of time integration schemes in ocean general circulation models. Mon. Wea. Rev, 125 , 23162327.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Williams, G. P., 1969: Numerical integration of the three-dimensional Navier–Stokes equations for incompressible flow. J. Fluid Mech, 37 , 727750.

    • Crossref
    • Search Google Scholar
    • Export Citation
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Impulsively Started Flow in a Submarine Canyon: Comparison of Results from Laboratory and Numerical Models

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  • 1 Environmental Fluid Dynamics Program, Department of Mechanical and Aerospace Engineering, Arizona State University, Tempe, Arizona
  • | 2 NOAA/Pacific Marine Environmental Laboratory, Seattle, Washington
  • | 3 Environmental Fluid Dynamics Program, Department of Mechanical and Aerospace Engineering, Arizona State University, Tempe, Arizona
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Abstract

Intercomparisons have been made of results from laboratory experiments and a numerical model for the flow in the vicinity of an idealized submarine canyon located along an otherwise continuous shelf. Motion in the rotating and continuously stratified fluid was impulsively generated by suddenly changing the period of rotation, so that the resulting flow occurred with the coastline either on the left (upwelling favorable) or right (downwelling favorable) when facing downstream. A principal purpose of the study was to further develop the notion that laboratory experiments can be effectively utilized to provide datasets to benchmark the development of numerical models. Laboratory data are of two types: velocity fields on three horizontal planes at numerous times, and time series of isopycnal movement in the canyon area. Comparison of numerical and laboratory results shows that values for bottom friction and interior mixing in the numerical model are crucial. Once those friction/mixing parameters are set, “skill” statistics using observed and predicted horizontal velocity components indicate that the high quality of the numerical model description is maintained over the full measurement period. Two principal features of the circulation are early (<one rotation period) along-canyon flow followed by generation of a canyon vortex. In up- (down-) welling cases, the cyclone (anticyclone) develops along the upstream edge of the canyon and then advects into the canyon interior without significant local vortex stretching within the canyon itself. Numerical results for the case of an extra slow rotation rate change show that vortex creation is not an artifact of the fast rate of rotation change. The canyon vortices extend from just slightly above shelf depth to the deepest part of the canyon; the intensities of the up- and downwelling vortices are asymmetric with respect to the direction of forcing at shelf level, but basically symmetric deeper in the canyon. Upper column vorticity generation by stretching over the canyon rim and flow separation around the canyon headlands could explain this upper water column asymmetric response. The symmetric response in the lower water column is shown to be related to the flow separation only.

Overall, the results demonstrate that laboratory and numerical experiments work hand in hand to decipher the complexities of circulation and hydrography undergoing rapid change in a model coastal canyon.

Corresponding author address: Dr. Don L. Boyer, Department of Mechanical and Aerospace Engineering, College of Engineering and Applied Sciences, Box 876106, Arizona State University, Tempe, AZ 85287-6106. Email: don.boyer@asu.edu

Abstract

Intercomparisons have been made of results from laboratory experiments and a numerical model for the flow in the vicinity of an idealized submarine canyon located along an otherwise continuous shelf. Motion in the rotating and continuously stratified fluid was impulsively generated by suddenly changing the period of rotation, so that the resulting flow occurred with the coastline either on the left (upwelling favorable) or right (downwelling favorable) when facing downstream. A principal purpose of the study was to further develop the notion that laboratory experiments can be effectively utilized to provide datasets to benchmark the development of numerical models. Laboratory data are of two types: velocity fields on three horizontal planes at numerous times, and time series of isopycnal movement in the canyon area. Comparison of numerical and laboratory results shows that values for bottom friction and interior mixing in the numerical model are crucial. Once those friction/mixing parameters are set, “skill” statistics using observed and predicted horizontal velocity components indicate that the high quality of the numerical model description is maintained over the full measurement period. Two principal features of the circulation are early (<one rotation period) along-canyon flow followed by generation of a canyon vortex. In up- (down-) welling cases, the cyclone (anticyclone) develops along the upstream edge of the canyon and then advects into the canyon interior without significant local vortex stretching within the canyon itself. Numerical results for the case of an extra slow rotation rate change show that vortex creation is not an artifact of the fast rate of rotation change. The canyon vortices extend from just slightly above shelf depth to the deepest part of the canyon; the intensities of the up- and downwelling vortices are asymmetric with respect to the direction of forcing at shelf level, but basically symmetric deeper in the canyon. Upper column vorticity generation by stretching over the canyon rim and flow separation around the canyon headlands could explain this upper water column asymmetric response. The symmetric response in the lower water column is shown to be related to the flow separation only.

Overall, the results demonstrate that laboratory and numerical experiments work hand in hand to decipher the complexities of circulation and hydrography undergoing rapid change in a model coastal canyon.

Corresponding author address: Dr. Don L. Boyer, Department of Mechanical and Aerospace Engineering, College of Engineering and Applied Sciences, Box 876106, Arizona State University, Tempe, AZ 85287-6106. Email: don.boyer@asu.edu

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