• Boehm, A., 2003: Model of microbial transport and inactivation in the surf zone and application to field measurements of total coliform in Northern Orange County, California. Environ. Sci. Technol., 37, 55115517, https://doi.org/10.1021/es034321x.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Boffetta, G., and R. Ecke, 2012: Two-dimensional turbulence. Annu. Rev. Fluid Mech., 44, 427451, https://doi.org/10.1146/annurev-fluid-120710-101240.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Boffetta, G., A. Celani, and M. Vergassola, 2000: Inverse energy cascade in two-dimensional turbulence : Deviations from Gaussian behavior. Phys. Rev. E, 61, R29R32, https://doi.org/10.1103/PhysRevE.61.R29.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bonneton, P., N. Bruneau, B. Castelle, and F. Marche, 2010: Large-scale vorticity generation due to dissipating waves in the surf zone. Discrete Contin. Dyn. Syst., 13B, 729738, https://doi.org/10.3934/dcdsb.2010.13.729.

    • Search Google Scholar
    • Export Citation
  • Bowen, A., and R. Holman, 1989: Shear instabilities of the mean alongshore current 1. Theory. J. Geophys. Res., 94, 18 02318 030, https://doi.org/10.1029/JC094iC12p18023.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bühler, O., 2000: On the vorticity transport due to dissipating or breaking waves in shallow-water flow. J. Fluid Mech., 407, 235263, https://doi.org/10.1017/S0022112099007508.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cartwright, D., and M. Longuet-Higgins, 1956: The statistical distribution of the maxima of a random function. Proc. Roy. Soc. London, 237A, 212232, https://doi.org/10.1098/rspa.1956.0173.

    • Search Google Scholar
    • Export Citation
  • Castelle, B., and Coauthors, 2010: Laboratory experiment on rip current circulations over a moveable bed: Drifter measurements. J. Geophys. Res., 115, C12008, https://doi.org/10.1029/2010JC006343.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cowen, R., C. Paris, and A. Srinivasan, 2006: Scaling of connectivity in marine populations. Science, 311, 522527, https://doi.org/10.1126/science.1122039.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Elgar, S., R. Guza, and R. Seymour, 1984: Groups of waves in shallow water. J. Geophys. Res., 89, 36233634, https://doi.org/10.1029/JC089iC03p03623.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Elgar, S., B. Raubenheimer, D. B. Clark, and M. Moulton, 2019: Extremely low frequency (0.1 to 1.0 mHz) surfzone currents. Geophys. Res. Lett., 46, 15311536, https://doi.org/10.1029/2018GL081106.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Feddersen, F., 2014: The generation of surfzone eddies in a strong alongshore current. J. Phys. Oceanogr., 44, 600617, https://doi.org/10.1175/JPO-D-13-051.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Feddersen, F., and R. Guza, 2003: Observations of nearshore circulation: Alongshore uniformity. J. Geophys. Res., 108, 3006, https://doi.org/10.1029/2001JC001293.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Geiman, J., and J. Kirby, 2013: Unforced oscillation of rip-current vortex cells. J. Phys. Oceanogr., 43, 477497, https://doi.org/10.1175/JPO-D-11-0164.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Gill, A., and E. Schumann, 1974: The generation of long shelf waves by wind. J. Phys. Oceanogr., 4, 8390, https://doi.org/10.1175/1520-0485(1974)004<0083:TGOLSW>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Goda, Y., 1970: Numerical experiments on wave statistics with spectral simulation. Port and Harbour Research Institute Rep., 57 pp., https://www.pari.go.jp/search-pdf/vol009-no03-01.pdf.

  • Grant, S., J. Kim, B. Jones, S. Jenkins, J. Wasyl, and C. Cudaback, 2005: Surf zone entrainment, along-shore transport, and human health implications of pollution from tidal outlets. J. Geophys. Res., 110, C10025, https://doi.org/10.1029/2004JC002401.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Haller, M., U. Putrevu, J. Oltman-Shay, and R. Dalrymple, 1999: Wave group forcing of low frequency surf zone motion. Coastal Eng. J., 41, 121136, https://doi.org/10.1142/S0578563499000085.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Halpern, B., and Coauthors, 2008: A global map of human impact on marine ecosystems. Science, 319, 948952, https://doi.org/10.1126/science.1149345.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Henderson, S., J. Arnold, H. Özkan-Haller, and S. Solovitz, 2017: Depth dependence of nearshore currents and eddies. J. Geophys. Res. Oceans, 122, 90049031, https://doi.org/10.1002/2016JC012349.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Johnson, D., and C. Pattiaratchi, 2006: Boussinesq modelling of transient rip currents. Coastal Eng., 53, 419439, https://doi.org/10.1016/j.coastaleng.2005.11.005.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kellay, H., and W. Goldburg, 2002: Two-dimensional turbulence: A review of some recent experiments. Rep. Prog. Phys., 65, 845894, https://doi.org/10.1088/0034-4885/65/5/204.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kennedy, A., M. Brocchini, L. Soldini, and E. Gutierrez, 2006: Topographically controlled, breaking-wave-induced macrovortices. Part 2. Changing geometries. J. Fluid Mech., 559, 5780, https://doi.org/10.1017/S0022112006009979.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kraichnan, R., 1967: Inertial ranges in two-dimensional turbulence. Phys. Fluids, 10, 14171423, https://doi.org/10.1063/1.1762301.

  • Kuik, A., G. Van Vledder, and L. Holthuijsen, 1988: A method for the routine analysis of pitch-and-roll buoy wave data. J. Phys. Oceanogr., 18, 10201034, https://doi.org/10.1175/1520-0485(1988)018<1020:AMFTRA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lippmann, T., T. Herbers, and E. Thornton, 1999: Gravity and shear wave contributions to nearshore infragravity motions. J. Phys. Oceanogr., 29, 231239, https://doi.org/10.1175/1520-0485(1999)029<0231:GASWCT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lippmann, T., E. Thornton, and T. Stanton, 2016: The vertical structure of low-frequency motions in the nearshore. Part I: Observations. J. Phys. Oceanogr., 46, 36953711, https://doi.org/10.1175/JPO-D-16-0014.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Long, J., and H. Özkan-Haller, 2009: Low-frequency characteristics of wave group-forced vortices. J. Geophys. Res., 114, C08004, https://doi.org/10.1029/2008JC004894.

    • Search Google Scholar
    • Export Citation
  • MacMahan, J., A. Reniers, E. Thornton, and T. Stanton, 2004: Surf zone eddies coupled with rip current morphology. J. Geophys. Res., 109, C07004, https://doi.org/10.1029/2003JC002083.

    • Search Google Scholar
    • Export Citation
  • MacMahan, J., A. Reniers, and E. Thornton, 2010: Vortical surf zone velocity fluctuations with 0(10) min period. J. Geophys. Res., 115, C06007, https://doi.org/10.1029/2009JC005383.

    • Search Google Scholar
    • Export Citation
  • Noyes, T., R. Guza, S. Elgar, and T. Herbers, 2004: Field observations of shear waves in the surf zone. J. Geophys. Res., 109, C01031, https://doi.org/10.1029/2002JC001761.

    • Search Google Scholar
    • Export Citation
  • Oltman-Shay, J., P. Howd, and W. Birkemeier, 1989: Shear instabilities of the mean longshore current: 2. Field observations. J. Geophys. Res., 94, 18 03118 042, https://doi.org/10.1029/JC094iC12p18031.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Özkan-Haller, H., and J. Kirby, 1999: Nonlinear evolution of shear instabilities of the longshore current: A comparison of observations and computations. J. Geophys. Res., 104, 25 95325 984, https://doi.org/10.1029/1999JC900104.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Peregrine, H., 1998: Surfzone currents. Comput. Fluid Dyn., 10, 295309, https://doi.org/10.1007/s001620050065.

  • Reniers, A., J. MacMahan, E. Thornton, and T. Stanton, 2007: Modeling of very low frequency motions during RIPEX. J. Geophys. Res., 112, C07013, https://doi.org/10.1029/2005JC003122.

    • Search Google Scholar
    • Export Citation
  • Smith, L. M., and V. Yakhot, 1994: Finite-size effects in forced two-dimensional turbulence. J. Fluid Mech., 274, 115138, https://doi.org/10.1017/S0022112094002065.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Spydell, M., 2016: The suppression of surfzone cross-shore mixing by alongshore currents. Geophys. Res. Lett., 43, 97819790, https://doi.org/10.1002/2016GL070626.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Spydell, M., and F. Feddersen, 2009: Lagrangian drifter dispersion in the surf zone: Directionally spread, normally incident waves. J. Phys. Oceanogr., 39, 809830, https://doi.org/10.1175/2008JPO3892.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Spydell, M., F. Feddersen, R. Guza, and W. Schmidt, 2007: Observing surf-zone dispersion with drifters. J. Phys. Oceanogr., 37, 29202939, https://doi.org/10.1175/2007JPO3580.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Spydell, M., F. Feddersen, and R. Guza, 2009: Observations of drifter dispersion in the surfzone: The effect of sheared alongshore currents. J. Geophys. Res., 114, C07028, https://doi.org/10.1029/2009JC005328.

    • Search Google Scholar
    • Export Citation
  • Tabeling, P., 2002: Two-dimensional turbulence: A physicist approach. Phys. Rep., 362, 162, https://doi.org/10.1016/S0370-1573(01)00064-3.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Uchiyama, Y., J. McWilliams, and C. Akan, 2017: Three-dimensional transient rip currents: Bathymetric excitation of low-frequency intrinsic variability. J. Geophys. Res. Oceans, 122, 58265849, https://doi.org/10.1002/2017JC013005.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wei, Z., R. Dalrymple, M. Xu, R. Garnier, and M. Derakhti, 2017: Short-crested waves in the surf zone. J. Geophys. Res. Oceans, 122, 41434162, https://doi.org/10.1002/2016JC012485.

    • Crossref
    • Search Google Scholar
    • Export Citation
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Field Evidence of Inverse Energy Cascades in the Surfzone

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  • 1 Woods Hole Oceanographic Institution, Woods Hole, Massachusetts
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Abstract

Low-frequency currents and eddies transport sediment, pathogens, larvae, and heat along the coast and between the shoreline and deeper water. Here, low-frequency currents (between 0.1 and 4.0 mHz) observed in shallow surfzone waters for 120 days during a wide range of wave conditions are compared with theories for generation by instabilities of alongshore currents, by ocean-wave-induced sea surface modulations, and by a nonlinear transfer of energy from breaking waves to low-frequency motions via a two-dimensional inverse energy cascade. For these data, the low-frequency currents are not strongly correlated with shear of the alongshore current, with the strength of the alongshore current, or with wave-group statistics. In contrast, on many occasions, the low-frequency currents are consistent with an inverse energy cascade from breaking waves. The energy of the low-frequency surfzone currents increases with the directional spread of the wave field, consistent with vorticity injection by short-crested breaking waves, and structure functions increase with spatial lags, consistent with a cascade of energy from few-meter-scale vortices to larger-scale motions. These results include the first field evidence for the inverse energy cascade in the surfzone and suggest that breaking waves and nonlinear energy transfers should be considered when estimating nearshore transport processes across and along the coast.

Corresponding author: Steve Elgar, elgar@whoi.edu

Abstract

Low-frequency currents and eddies transport sediment, pathogens, larvae, and heat along the coast and between the shoreline and deeper water. Here, low-frequency currents (between 0.1 and 4.0 mHz) observed in shallow surfzone waters for 120 days during a wide range of wave conditions are compared with theories for generation by instabilities of alongshore currents, by ocean-wave-induced sea surface modulations, and by a nonlinear transfer of energy from breaking waves to low-frequency motions via a two-dimensional inverse energy cascade. For these data, the low-frequency currents are not strongly correlated with shear of the alongshore current, with the strength of the alongshore current, or with wave-group statistics. In contrast, on many occasions, the low-frequency currents are consistent with an inverse energy cascade from breaking waves. The energy of the low-frequency surfzone currents increases with the directional spread of the wave field, consistent with vorticity injection by short-crested breaking waves, and structure functions increase with spatial lags, consistent with a cascade of energy from few-meter-scale vortices to larger-scale motions. These results include the first field evidence for the inverse energy cascade in the surfzone and suggest that breaking waves and nonlinear energy transfers should be considered when estimating nearshore transport processes across and along the coast.

Corresponding author: Steve Elgar, elgar@whoi.edu
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