• Alessi, C. A., S. J. Lentz, and R. C. Beardsley, 1991: The Shelf Mixed Layer Experiment (SMILE): Program overiew and moored and coastal array data report. WHOI Tech. Rep. 91-39, 211 pp. [Woods Hole Oceanographic Institution, Woods Hole, MA 02543-1541.].

  • Allen, J. S., and P. K. Kundu, 1978: On the momentum, vorticity and mass balance on the Oregon shelf. J. Phys. Oceanogr.,8, 13–27.

  • Badan-Dangon, A., K. H. Brink, and R. L. Smith, 1986: On the dynamical structure of the mid-shelf water column off northwest Africa. Contin. Shelf Res.,5, 629–644.

  • Barth, J. A., 1994: Short-wavelength instabilities on coastal jets and fronts. J. Geophys. Res.,99, 16 095–16 115.

  • Beardsley, R. C., and S. J. Lentz, 1987: The Coastal Ocean Dynamics Experiment collection: An introduction. J. Geophys. Res.,92, 1455–1464.

  • Brink, K. H., J. H. LaCasce, and J. D. Irish, 1994: The effect of short-scale wind variations on shelf currents. J. Geophys. Res.,99, 3305–3314.

  • Brown, W. S., J. D. Irish, and C. D. Winant, 1987: A description of subtidal pressure field observations on the northern California continental shelf during the Coastal Ocean Dynamics Experiment. J. Geophys. Res.,92, 1605–1635.

  • Bryden, H. L., D. Halpern, and R. D. Pillsbury, 1980: Importance of eddy heat flux in a heat budget for Oregon coastal waters. J. Geophys. Res.,85, 6649–6653.

  • Chapman, D. C., 1987: Application of wind-forced, long, coastal-trapped wave theory along the California coast. J. Geophys. Res.,92, 1798–1816.

  • Chen, D., 1990: Dynamics of time-variable coastal upwelling. Ph.D. thesis, State University of New York at Stony Brook, 83 pp.

  • ——, and D.-P. Wang, 1990: Simulating the time-variable coastal upwelling during CODE-2. J. Mar. Res.,48, 335–338.

  • Csanady, G. T., 1982: Circulation in the Coastal Ocean. D. Reidel, 279 pp.

  • Davis, R. E., and P. S. Bogden, 1989: Variability on the California shelf forced by local and remote winds during the coastal ocean dynamics experiment. J. Geophys. Res.,94, 4673–4783.

  • de Szoeke, R. A., and J. G. Richman, 1984: On wind-driven mixed layers with strong horizontal gradients—A theory with application to coastal upwelling. J. Phys. Oceanogr.,14, 364–377.

  • Dever, E. P., 1995: Subtidal cross-shelf circulation on the northern California shelf. Ph.D. thesis, Massachusetts Institute of Technology/Woods Hole Oceanographic Institution. [Woods Hole Oceanographic Institution, Woods Hole, MA 02543-1541.].

  • ——, and S. J. Lentz, 1994: Heat and salt balances over the northern California shelf in winter and spring. J. Geophys. Res.,99, 16 001–16 017.

  • Dickey, T. D., and J. C. Van Leer, 1984: Observations and simulation of a bottom Ekman layer on a continental shelf. J. Geophys. Res.,89, 1983–1988.

  • Draper, N. R., and H. Smith, 1966: Applied Regression Analysis. John Wiley & Sons, 407 pp.

  • Fredericks, J. J., J. H. Trowbridge, A. J. Williams III, S. J. Lentz, B. Butman, and T. F. Gross, 1993: Fluid mechanical measurements within the bottom boundary layer over the northern California continental shelf during STRESS. WHOI Tech. Rep. 93-32, 116 pp. [Woods Hole Oceanographic Institute, Woods Hole, MA 02543-1541.].

  • Grant, W. D., A. J. Williams, and S. M. Glenn, 1984: Bottom stress estimates and their prediction on the northern California continental shelf during CODE-1: The importance of wave-current interaction. J. Phys. Oceanogr.,14, 506–527.

  • Gross, T. F., A. E. Isley, and C. R. Sherwood, 1992: Estimation of stress and bed roughness during storms on the northern California shelf. Contin. Shelf Res.,12, 389–413.

  • Halpern, D., R. L. Smith, and E. Mittelstaedt, 1977: Cross-shelf circulation on the continental shelf off northwest Africa during upwelling. J. Mar. Res.,35, 787–796.

  • Hickey, B. M., and N. E. Pola, 1983: The seasonal alongshore pressure gradient on the west coast of the United States. J. Geophys. Res.,88, 7623–7633.

  • Janowitz, G. S., and L. J. Pietrafesa, 1980: A model and observations of time-dependent upwelling over the mid-shelf and slope. J. Phys. Oceanogr.,10, 1574–1583.

  • Jenter, H. L., and O. S. Madsen, 1989: Bottom stress in wind-driven depth-averaged coastal flows. J. Phys. Oceanogr.,19, 962–974.

  • Kosro, P. M., A. Huyer, S. R. Ramp, R. L. Smith, F. P. Chavez, T. J. Cowles, M. R. Abbott, P. T. Strub, R. T. Barber, P. Jessen, and L. F. Small, 1991: The structure of the transition zone between coastal waters and the open ocean off northern California, winter and spring 1987. J. Geophys. Res.,96, 14 707–14 730.

  • Kundu, P. K., 1976: Ekman veering observed near the ocean bottom. J. Phys. Oceanogr.,6, 238–242.

  • ——, and J. S. Allen, 1976: Some three-dimensional characteristics of low-frequency current fluctuations near the Oregon coast. J. Phys. Oceanogr.,6, 181–199.

  • ——, and R. C. Beardsley, 1991: Evidence of a critical Richardson number in moored measurements during the upwelling season off northern California. J. Geophys. Res.,96, 4855–4868.

  • Large, W. G., and S. Pond, 1981: Open ocean momentum flux measurements in moderate to strong winds. J. Phys. Oceanogr.,11, 324–336.

  • Lentz, S. J., 1987a: A heat budget for the northern California shelf during CODE 2. J. Geophys. Res.,92, 14 491–14 509.

  • ——, 1987b: A description of the 1981 and 1982 spring transitions over the northern California shelf. J. Geophys. Res.,92, 1545–1567.

  • ——, 1992: The surface boundary layer in coastal upwelling regions. J. Phys. Oceanogr.,22, 1517–1539.

  • ——, and J. H. Trowbridge, 1991: The bottom boundary layer over the northern California shelf. J. Phys. Oceanogr.,21, 1186–1201.

  • Limeburner, R., Ed., 1985: CODE-2: Moored array and large-scale data report. WHOI Tech. Rep. 85-35, 234 pp. [Available from Woods Hole Oceanographic Institution, Woods Hole, MA 02543-1541.].

  • López, M., and A. J. Clarke, 1989: The wind-driven shelf and slope water flow in terms of a local and remote response. J. Phys. Oceanogr.,19, 1092–1101.

  • Pedlosky, J., 1979: Geophysical Fluid Dynamics. Springer-Verlag, 624 pp.

  • Richman, J. G., and A. Badan-Dangon, 1983: Mean heat and momentum budgets during upwelling for the coastal waters off northwest Africa. J. Geophys. Res.,88, 2626–2632.

  • Rudnick, D. L., and R. E. Davis, 1988: Mass and heat budgets on the northern California shelf. J. Geophys. Res.,93, 14 013–14 024.

  • Send, U., R. C. Beardsley, and C. D. Winant, 1987: Relaxation from upwelling in the coastal ocean dynamics experiment. J. Geophys. Res.,92, 1683–1698.

  • Smith, R. L., 1981: A comparison of the structure and variability of the flow field in three coastal upwelling regions: Oregon, northwest Africa, and Peru. Coastal Upwelling, F. A. Richards, Ed., Amer. Geophys. Union, 107–118.

  • Trowbridge, J. H., and S. J. Lentz, 1991: Asymmetric behavior of an oceanic boundary layer above a sloping bottom. J. Phys. Oceanogr.,21, 1171–1185.

  • Weatherly, G. L., and P. J. Martin, 1978: On the structure and dynamics of the oceanic bottom boundary layer. J. Phys. Oceanogr.,8, 557–570.

  • Winant, C. D., R. C. Beardsley, and R. E. Davis, 1987: Moored wind, temperature, and current observations made during coastal ocean dynamics experiments 1 and 2 over the northern California shelf and upper slope. J. Geophys. Res.,92, 1569–1604.

  • Zamudio, L., and M. López, 1994: On the effect of the alongshore pressure gradient on numerical simulations over the northern California shelf. J. Geophys. Res.,99, 16 117–16 129.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 126 126 1
PDF Downloads 21 21 0

Wind-Forced Cross-Shelf Circulation on the Northern California Shelf

View More View Less
  • 1 Center for Coastal Studies, Scripps Institution of Oceanography, La Jolla, California
© Get Permissions Rent on DeepDyve
Restricted access

Abstract

Velocity time series are used to study cross-shelf circulation on the northern California shelf and to examine classical ideas of locally wind-forced cross-shelf circulation. A simple linear two-dimensional model of cross-shelf transport is compared to estimates of cross-shelf transport in the near surface, interior, and near bottom. In winter, when wind forcing is brief and episodic, model transports are highly correlated to the total surface flow and show some skill in predicting subsurface cross-shelf flow. The same model does not work well below the surface in summer when persistent upwelling is observed. This suggests a two-dimensional wind-forced model of cross-shelf circulation may have more applicability to the brief wind events observed in winter than to the persistent wind events observed in summer. The reason for this is unclear. Numerous factors not included in the simple linear wind-forced model such as mesoscale features, upwelling fronts, the interaction of flow with topography, baroclinic pressure gradients, remote forcing, and small-scale wind stress all affect cross-shelf circulation. It is possible some of these are more pronounced on the northern California shelf in summer.

Corresponding author address: Dr. Edward P. Dever, Center for Coastal Studies - 0209, Scripps Institution of Oceanography, University of California at San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0209.

Email: dever@coast.ucsd.edu

Abstract

Velocity time series are used to study cross-shelf circulation on the northern California shelf and to examine classical ideas of locally wind-forced cross-shelf circulation. A simple linear two-dimensional model of cross-shelf transport is compared to estimates of cross-shelf transport in the near surface, interior, and near bottom. In winter, when wind forcing is brief and episodic, model transports are highly correlated to the total surface flow and show some skill in predicting subsurface cross-shelf flow. The same model does not work well below the surface in summer when persistent upwelling is observed. This suggests a two-dimensional wind-forced model of cross-shelf circulation may have more applicability to the brief wind events observed in winter than to the persistent wind events observed in summer. The reason for this is unclear. Numerous factors not included in the simple linear wind-forced model such as mesoscale features, upwelling fronts, the interaction of flow with topography, baroclinic pressure gradients, remote forcing, and small-scale wind stress all affect cross-shelf circulation. It is possible some of these are more pronounced on the northern California shelf in summer.

Corresponding author address: Dr. Edward P. Dever, Center for Coastal Studies - 0209, Scripps Institution of Oceanography, University of California at San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0209.

Email: dever@coast.ucsd.edu

Save