Search Results

You are looking at 71 - 80 of 474 items for :

  • Langmuir circulation x
  • Refine by Access: All Content x
Clear All
Jerome A. Smith

energy, and 2) changes in wave momentum that absorb some of the radiation stress gradients. Garrett and Smith (1976) combined the radiation stress and mass balance into a consistent framework, resolving these issues. Using action conservation to account for variations in the wave momentum budget, and subtracting this from the radiation stress divergence, Garrett (1976) derived an effective “wave force” on the mean flow, and suggested a mechanism for the generation of Langmuir circulation, which

Full access
Eric A. D’Asaro and Geoffrey T. Dairiki

energy between them. The Craik–Leibovich theory ( Leibovich 1983 ) shows how these interactions can produce “Langmuir circulations,” which efficiently mix the upper ocean. Li and Garrett (1993) study the properties of these circulations in detail and propose an upper-ocean model ( Li and Garrett 1997 ) in which these circulations play a key role. The development of mixed layer models has been greatly hindered by the lack of appropriate data. Time-varying profiles of temperature, salinity, and

Full access
Antony K. Liu, Seelye Martin, and Ronald Kwok

. Lawrence Island polynya. The young ice area of polynya within each SAR image can be estimated and its growth rate is found to be 2.52 exp(day/3.36). b. The active polynya region For the active polynya region on 27 February, Fig. 5 shows the long, linear streaks characteristic of the Langmuir circulation and its 2D FFT. The transformed image in Fig. 5b shows that the Langmuir cells have many scales with one peak at 120 m and another at approximately 230 m. Figure 6 shows the use of this Fourier and

Full access
Jerome A. Smith

1969 ; Longuet-Higgins 1970a , b ); the interaction of freely propagating long and short surface waves ( Longuet-Higgins 1969 ; Hasselmann 1971 ; Garrett and Smith 1976 ; and many others); and the generation of Langmuir circulation (LC), a prominent form of motion in the wind-driven surface mixed layer (e.g., Langmuir 1938 ; Craik 1977 ; Leibovich 1980 ; Li et al. 1995 ; Skyllingstad and Denbo 1995 ; McWilliams et al. 1997 ; McWilliams and Sullivan 2000 ; Phillips 2002 ; Sullivan et al

Full access
Gregory P. Gerbi, John H. Trowbridge, James B. Edson, Albert J. Plueddemann, Eugene A. Terray, and Janet J. Fredericks

for generating turbulence. In the ocean’s surface boundary layer (mixed layer), the physical mechanisms thought to be important in turbulence production include boundary stress, boundary buoyancy flux, wave breaking, and Langmuir circulation. This study was undertaken in conditions conducive to the formation of turbulence by all of these mechanisms, and we hope that it will aid in our understanding of mixed layer turbulence dynamics and in our ability to parameterize such turbulence in closure

Full access
Yign Noh, Gahyun Goh, Siegfried Raasch, and Micha Gryschka

clarify its dynamical process by analysis of LES data. In particular, investigation was focused on how turbulence at the thermocline is modified during the formation of a diurnal thermocline. It was also investigated how the result is affected by Langmuir circulation (LC), WB, radiation penetration, and the diurnal variation of the surface buoyancy flux. 2. Simulation For the simulation, we used the LES model for the ocean mixed layer developed by Noh et al. (2004) , in which both LC and WB are

Full access
Rebecca R. Schudlich and James F. Price

sources including a surface-intensified geostrophic flow coupled to the local wind through Ekman pumping, Langmuir circulation, a logarithmic boundary layer, or a surface-wave induced bias. We cannot quantify Ekman pumping with the LOTUS data and can only give generic estimates of the effects of Langmuir circulations, which we do below. Here we will consider in detail the latter two processes that could produce a downwind shear in the near-surface layer: (i) a logarithmic boundary layer (“wall layer

Full access
S. A. Thorpe

the size distribution. Factors contributingto this discrepancy are discussed. It is possible that bubble populations measured by floating cameras are biasedbecause of the effects of Langmuir circulation both on the float and on the bubbles.1. Introduction Subsurface bubbles formed by breaking wind waveshave been subject to investigation for some time, primarily because of their role in the formation of aerosolswhen the bubbles burst on returning to the surface(Blanchard and Woodcock, 1957

Full access
Jeff A. Polton, David M. Lewis, and Stephen E. Belcher

for Langmuir circulations ( Leibovich 1983 ; McWilliams et al. 1997 ; Teixeira and Belcher 2002 ). The interaction of the Stokes drift with planetary vorticity is the subject of this paper. The effects of Stokes drift in a rotating frame was first considered by Ursell (1950) , Hasselmann (1970) and Pollard (1970) who showed that, for an inviscid ocean, there can be no net mass transport associated with the Stokes drift. Subsequently, also using a Lagrangian description, Weber (1983a) , b

Full access
Fabrice Ardhuin, Louis Marié, Nicolas Rascle, Philippe Forget, and Aron Roland

the Ekman depth is generally on the order of 30 m, it follows that the classical Ekman theory, with a constant eddy viscosity, does not apply here. Instead, this large near-surface deflection is consistent with model results obtained with a high surface mixing—such as those induced by Langmuir circulations ( McWilliams et al. 1997 ; Kantha and Clayson 2004 ), breaking waves ( Craig and Banner 1994 ; Mellor and Blumberg 2004 ; Rascle et al. 2006 ), or both—and consistent with the few observed

Full access