• Barth, J. A., , S. D. Pierce, , and R. L. Smith, 2000: A separating coastal upwelling jet at Cape Blanco, Oregon and its connection to the California Current System. Deep-Sea Res. II, 47, 783810, doi:10.1016/S0967-0645(99)00127-7.

    • Search Google Scholar
    • Export Citation
  • Brink, K. H., 1982: A comparison of long coastal trapped wave theory with observations off Peru. J. Phys. Oceanogr., 12, 897913, doi:10.1175/1520-0485(1982)012<0897:ACOLCT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Cartwright, D. E., 1969: Extraordinary tidal currents near St. Kilda. Nature, 223, 928932, doi:10.1038/223928a0.

  • Chapman, D. C., 1983: On the influence of stratification and continental shelf and slope topography on the dispersion of subinertial coastally trapped waves. J. Phys. Oceanogr., 13, 16411652, doi:10.1175/1520-0485(1983)013<1641:OTIOSA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Crawford, W. R., , and R. E. Thomson, 1982: Continental shelf waves of diurnal period along Vancouver Island. J. Geophys. Res., 87, 95169527, doi:10.1029/JC087iC12p09516.

    • Search Google Scholar
    • Export Citation
  • Crawford, W. R., , and R. E. Thomson, 1984: Diurnal-period continental shelf waves along Vancouver Island: A comparison of observation with theoretical models. J. Phys. Oceanogr., 14, 16291646, doi:10.1175/1520-0485(1984)014<1629:DPCSWA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Cummins, P. F., , D. Masson, , and M. G. G. Foreman, 2000: Stratification and mean flow effects on diurnal tidal currents off Vancouver Island. J. Phys. Oceanogr., 30, 1530, doi:10.1175/1520-0485(2000)030<0015:SAMFEO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Egbert, G. D., , and S. Y. Erofeeva, 2002: Efficient inverse modeling of barotropic ocean tides. J. Atmos. Oceanic Technol., 19, 183204, doi:10.1175/1520-0426(2002)019<0183:EIMOBO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Erofeeva, S. Y., , G. D. Egbert, , and P. M. Kosro, 2003: Tidal currents on the central Oregon shelf: Models, data, and assimilation. J. Geophys. Res., 108, 3148, doi:10.1029/2002JC001615.

    • Search Google Scholar
    • Export Citation
  • Geyer, W. R., 1993: Three-dimensional tidal flow around headlands. J. Geophys. Res., 98, 955966, doi:10.1029/92JC02270.

  • Hayes, S. P., , and D. Halpern, 1976: Observations of internal waves and coastal upwelling on the Oregon coast. J. Mar. Res., 34, 247267.

    • Search Google Scholar
    • Export Citation
  • Hodur, R. M., 1997: The Naval Research Laboratory’s Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS). Mon. Wea. Rev., 125, 14141430, doi:10.1175/1520-0493(1997)125<1414:TNRLSC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Kalnay, E., and Coauthors, 1996: The NCEP/NCAR 40-Year Reanalysis Project. Bull. Amer. Meteor. Soc., 77, 437471, doi:10.1175/1520-0477(1996)077<0437:TNYRP>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Kim, S., , and J. A. Barth, 2011: Connectivity and larval dispersal along the Oregon coast estimated by numerical simulations. J. Geophys. Res.,116, L06002, doi:10.1029/2010JC006741.

  • Koch, A. O., , A. L. Kurapov, , and J. S. Allen, 2010: Near-surface dynamics of a separated jet in the coastal transition zone off Oregon. J. Geophys. Res.,115, C08020, doi:10.1029/2009JC005704.

  • Kosro, P. M., 2005: On the spatial structure of coastal circulation off Newport, Oregon, during spring and summer 2001 in a region of varying shelf width. J. Geophys. Res., 110, C10S06, doi:10.1029/2004JC002769.

    • Search Google Scholar
    • Export Citation
  • Kosro, P. M., , W. T. Peterson, , B. M. Hickey, , R. K. Shearman, , and S. D. Pierce, 2006: Physical versus the biological spring transition: 2005. Geophys. Res. Lett., 33, L22S03, doi:10.1029/2006GL027072.

    • Search Google Scholar
    • Export Citation
  • Kovalev, P. D., , and A. B. Rabinovich, 1980: Bottom measurements of tidal currents in the southern part of the Kuril-Kamchatka Trench. Oceanology, 20, 294299.

    • Search Google Scholar
    • Export Citation
  • Kurapov, A. L., , G. D. Egbert, , J. S. Allen, , R. N. Miller, , S. Y. Erofeeva, , and P. M. Kosro, 2003: The M2 internal tide off Oregon: Inferences from data assimilation. J. Phys. Oceanogr., 33, 17331757, doi:10.1175/2397.1.

    • Search Google Scholar
    • Export Citation
  • Kurapov, A. L., , D. Foley, , P. T. Strub, , G. D. Egbert, , and J. S. Allen, 2011: Variational assimilation of satellite observations in a coastal ocean model off Oregon. J. Geophys. Res.,116, C05006, doi:10.1029/2010JC006909.

  • Liu, W. T., 2002: Progress in scatterometer application. J. Oceanogr., 58, 121136, doi:10.1023/A:1015832919110.

  • Liu, W. T., , and X. Xie, 2001: Improvement in spacebased scatterometers and increased scientific impact in the past decade. Proc. Oceans 2001, Vol. 1, Honolulu, HI, Marine Technology Society, 626–630.

  • Maturi, E., , A. Harris, , C. Merchant, , J. Mittaz, , B. Potash, , W. Meng, , and J. Sapper, 2008: NOAA’s sea surface temperature products from operational geostationary satellites. Bull. Amer. Meteor. Soc., 89, 18771888, doi:10.1175/2008BAMS2528.1.

    • Search Google Scholar
    • Export Citation
  • McCabe, R. M., , P. MacCready, , and G. Pawlak, 2006: Form drag due to flow separation at a headland. J. Phys. Oceanogr., 36, 21362152, doi:10.1175/JPO2966.1.

    • Search Google Scholar
    • Export Citation
  • Odamaki, M., 1994: Tides and tidal currents along the Okhotsk coast of Hokkaido. J. Oceanogr., 50, 265279, doi:10.1007/BF02239517.

  • Oliger, J., , and A. Sundström, 1978: Theoretical and practical aspects of some initial boundary value problems in fluid dynamics. SIAM J. Appl. Math., 35, 419446, doi:10.1137/0135035.

    • Search Google Scholar
    • Export Citation
  • Osborne, J. J., , A. L. Kurapov, , G. D. Egbert, , and P. M. Kosro, 2011: Spatial and temporal variability of the M2 internal tide generation and propagation on the Oregon shelf. J. Phys. Oceanogr., 41,20372062, doi:10.1175/JPO-D-11-02.1.

    • Search Google Scholar
    • Export Citation
  • Pawlowicz, R., , B. Beardsley, , and S. Lentz, 2002: Classical tidal harmonic analysis including error estimates in MATLAB using T_TIDE. Comput. Geosci., 28, 929937, doi:10.1016/S0098-3004(02)00013-4.

    • Search Google Scholar
    • Export Citation
  • Perlin, N., , R. M. Samelson, , and D. B. Chelton, 2004: Scatterometer and model wind and wind stress in the northern California coastal zone. Mon. Wea. Rev., 132, 21102129, doi:10.1175/1520-0493(2004)132<2110:SAMWAW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Pugh, D. T., 1987: Tides, Surges, and Mean Sea-Level. John Wiley and Sons, 472 pp.

  • Rabinovich, A. B., , and A. E. Zhukov, 1984: Tidal oscillations on the shelf of Sakhalin Island. Oceanology, 24, 184189.

  • Rabinovich, A. B., , and R. E. Thomson, 2001: Evidence of diurnal shelf waves in satellite-tracked drifter trajectories off the Kuril Islands. J. Phys. Oceanogr., 31, 26502668, doi:10.1175/1520-0485(2001)031<2650:EODSWI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Saraceno, M., , P. T. Strub, , and P. M. Kosro, 2008: Estimates of sea surface height and near-surface alongshore coastal currents from combinations of altimeters and tide gauges. J. Geophys. Res.,113, C11013, doi:10.1029/2008JC004756.

  • Shchepetkin, A. F., , and J. C. McWilliams, 2005: The Regional Oceanic Modeling Systems (ROMS): A split-explicit, free-surface, topography-following-coordinate oceanic model. Ocean Modell., 9, 347404, doi:10.1016/j.ocemod.2004.08.002.

    • Search Google Scholar
    • Export Citation
  • Signell, R. P., , and W. R. Geyer, 1991: Transient eddy formation around headlands. J. Geophys. Res., 96, 25612575, doi:10.1029/90JC02029.

    • Search Google Scholar
    • Export Citation
  • Smith, R. L., , A. Huyer, , and J. Fleischbein, 2001: The coastal ocean off Oregon from 1961 to 2000: Is there evidence of climate change or only of Los Niños? Prog. Oceanogr., 49, 6393, doi:10.1016/S0079-6611(01)00016-7.

    • Search Google Scholar
    • Export Citation
  • Strub, P. T., , P. M. Kosro, , A. Huyer, , and C. Collaborators, 1991: The nature of the cold filaments in the California Current System. J. Geophys. Res., 96, 14 74314 768, doi:10.1029/91JC01024.

    • Search Google Scholar
    • Export Citation
  • Torgrimson, G. M., , and B. M. Hickey, 1979: Barotropic and baroclinic tides over the continental slope and shelf off Oregon. J. Phys. Oceanogr., 9, 945961, doi:10.1175/1520-0485(1979)009<0945:BABTOT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Yefimov, V. V., , and A. B. Rabinovich, 1980: Resonant tidal currents and their relation to continental shelf waves of the northwestern Pacific Ocean. Izv. Atmos. Ocean. Phys., 16, 805812.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 14 14 2
PDF Downloads 7 7 2

Intensified Diurnal Tides along the Oregon Coast

View More View Less
  • 1 College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon
© Get Permissions
Restricted access

Abstract

Intensified diurnal tides are found along portions of the Oregon shelf (U.S. West Coast) based on analyses of high-frequency (HF) radar surface current data and outputs of a 1-km resolution ocean circulation model. The K1 tidal currents with magnitudes near 0.07 m s−1 over a wider part of the shelf (Heceta Bank complex; 44°–44.5°N), previously predicted by Erofeeva et al., are confirmed here by newly available HF radar data. Intensified diurnal tides are also found along the narrow shelf south of Heceta Bank. In the close vicinity of Cape Blanco (42.8°N), diurnal tidal currents (K1 and O1 constituents combined) may reach 0.3 m s−1. Appreciable differences in diurnal tide intensity are found depending on whether the model is forced with tides and winds (TW) or only tides. Also, diurnal variability in wind forcing is found to affect diurnal surface velocities. For the case forced by tides alone, results strongly depend on whether the model ocean is stratified [tides only, stratified (TOS)] or not [tides only, no stratification (TONS)]. In case TONS, coastal-trapped waves at diurnal frequencies do not occur over the narrow shelf south of 43.5°N, consistent with the dispersion analysis of a linear shallow-water model. However, in case TOS, diurnal tides are intensified in that area, associated with the presence of coastal-trapped waves. Case TW produces the strongest modeled diurnal tidal motions over the entire Oregon shelf, partially due to cross-shore tidal displacement (advection) of alongshore subinertial currents. At Cape Blanco, diurnal tidal variability dominates the modeled relative vorticity spectrum, suggesting that tides may influence the separation of the alongshore coastal jet at that location.

Corresponding author address: John Osborne, College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, 104 CEOAS Administration Building, Corvallis, OR 97331. E-mail: josborne@coas.oregonstate.edu

Abstract

Intensified diurnal tides are found along portions of the Oregon shelf (U.S. West Coast) based on analyses of high-frequency (HF) radar surface current data and outputs of a 1-km resolution ocean circulation model. The K1 tidal currents with magnitudes near 0.07 m s−1 over a wider part of the shelf (Heceta Bank complex; 44°–44.5°N), previously predicted by Erofeeva et al., are confirmed here by newly available HF radar data. Intensified diurnal tides are also found along the narrow shelf south of Heceta Bank. In the close vicinity of Cape Blanco (42.8°N), diurnal tidal currents (K1 and O1 constituents combined) may reach 0.3 m s−1. Appreciable differences in diurnal tide intensity are found depending on whether the model is forced with tides and winds (TW) or only tides. Also, diurnal variability in wind forcing is found to affect diurnal surface velocities. For the case forced by tides alone, results strongly depend on whether the model ocean is stratified [tides only, stratified (TOS)] or not [tides only, no stratification (TONS)]. In case TONS, coastal-trapped waves at diurnal frequencies do not occur over the narrow shelf south of 43.5°N, consistent with the dispersion analysis of a linear shallow-water model. However, in case TOS, diurnal tides are intensified in that area, associated with the presence of coastal-trapped waves. Case TW produces the strongest modeled diurnal tidal motions over the entire Oregon shelf, partially due to cross-shore tidal displacement (advection) of alongshore subinertial currents. At Cape Blanco, diurnal tidal variability dominates the modeled relative vorticity spectrum, suggesting that tides may influence the separation of the alongshore coastal jet at that location.

Corresponding author address: John Osborne, College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, 104 CEOAS Administration Building, Corvallis, OR 97331. E-mail: josborne@coas.oregonstate.edu
Save