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1. Introduction Among various processes that occur in the oceanic surface boundary layer, Langmuir circulations (LCs) receive attention because they are believed to modulate the air–sea heat/material exchange through an enhancement of turbulent mixing ( Langmuir 1938 ; Smith 1992 ; Belcher et al. 2012 ; D’Asaro 2014 ; Li et al. 2016 ). In the formation of LCs, the interaction between surface waves and mean flow is believed to play a central role. Craik and Leibovich (1976 , hereinafter CL
1. Introduction Among various processes that occur in the oceanic surface boundary layer, Langmuir circulations (LCs) receive attention because they are believed to modulate the air–sea heat/material exchange through an enhancement of turbulent mixing ( Langmuir 1938 ; Smith 1992 ; Belcher et al. 2012 ; D’Asaro 2014 ; Li et al. 2016 ). In the formation of LCs, the interaction between surface waves and mean flow is believed to play a central role. Craik and Leibovich (1976 , hereinafter CL
the CL2 mechanism ( Craik and Leibovich 1976 ). Pairs of vortices are spaced at regular intervals with a separation of about two times the boundary layer depth, forming coherent dynamical structures called Langmuir circulations (LCs) ( Thorpe 2004 ). At the surface, pairs of roll vortices form convergence zones which concentrate buoyant particles such as algae or bubbles into elongated windrows, the commonly recognized surface expression of LCs ( Langmuir 1938 ; Farmer and Li 1995 ). Below these
the CL2 mechanism ( Craik and Leibovich 1976 ). Pairs of vortices are spaced at regular intervals with a separation of about two times the boundary layer depth, forming coherent dynamical structures called Langmuir circulations (LCs) ( Thorpe 2004 ). At the surface, pairs of roll vortices form convergence zones which concentrate buoyant particles such as algae or bubbles into elongated windrows, the commonly recognized surface expression of LCs ( Langmuir 1938 ; Farmer and Li 1995 ). Below these
near oceanic fronts ( D’Asaro et al. 2018 ). Here we seek to begin to fill that gap, using an innovative dataset of optically tracked floating bamboo plates ( Carlson et al. 2018 ), which provides higher space and time resolution for the trajectories than available from classic Lagrangian drifter and float data. Specifically, we focus on the dispersive properties during a Langmuir event. Langmuir circulation (LC) is characterized by counterrotating vortices aligned with the wind direction
near oceanic fronts ( D’Asaro et al. 2018 ). Here we seek to begin to fill that gap, using an innovative dataset of optically tracked floating bamboo plates ( Carlson et al. 2018 ), which provides higher space and time resolution for the trajectories than available from classic Lagrangian drifter and float data. Specifically, we focus on the dispersive properties during a Langmuir event. Langmuir circulation (LC) is characterized by counterrotating vortices aligned with the wind direction
1206 JOURNAL OF PHYSICAL OCEANOGRAPHY VOLUME25Secondary Instabilities in Langmuir Circulations AMIT TANDONSchool of Earth and Ocean Sciences, University of Victoria, Victoria. British Columbia, Canada SIDNEY LEIBOVICHSibley School of Mechanical and ,4erospace Engineering, Come# University. Ithaca, New York(Manuscript received 10 January 1994, in final form 23 September 1994
1206 JOURNAL OF PHYSICAL OCEANOGRAPHY VOLUME25Secondary Instabilities in Langmuir Circulations AMIT TANDONSchool of Earth and Ocean Sciences, University of Victoria, Victoria. British Columbia, Canada SIDNEY LEIBOVICHSibley School of Mechanical and ,4erospace Engineering, Come# University. Ithaca, New York(Manuscript received 10 January 1994, in final form 23 September 1994
FEBRUARY 1983 ALAN J. FALLER AND RANDALL W. CARTWRIGHT 329Laboratory Studies of Langmuir Circulations ALAN J. FALLERInstitute for Physical Science and Technology, University of Maryland, College Park 20742 RANDALL W. CARTWRIGHT1Department of Meteorology, University of Maryland, College Park 20742(Manuscript received 21 May 1982, in final form 27 September 1982
FEBRUARY 1983 ALAN J. FALLER AND RANDALL W. CARTWRIGHT 329Laboratory Studies of Langmuir Circulations ALAN J. FALLERInstitute for Physical Science and Technology, University of Maryland, College Park 20742 RANDALL W. CARTWRIGHT1Department of Meteorology, University of Maryland, College Park 20742(Manuscript received 21 May 1982, in final form 27 September 1982
1. Introduction When the wind blows across a stratified ocean, a surface mixed layer (SML) develops in which the density is approximately uniform. The lower boundary is marked by a strongly stratified transition region. The density jump across this increases as the mixed layer deepens. Shear-driven turbulence may contribute to the mixing and density homogenization in the SML during wind events, but another important process is wind-driven Langmuir circulation (LC). This consists of a pattern of
1. Introduction When the wind blows across a stratified ocean, a surface mixed layer (SML) develops in which the density is approximately uniform. The lower boundary is marked by a strongly stratified transition region. The density jump across this increases as the mixed layer deepens. Shear-driven turbulence may contribute to the mixing and density homogenization in the SML during wind events, but another important process is wind-driven Langmuir circulation (LC). This consists of a pattern of
structure of the vertical stratification and the development of the surface boundary layer. More significant, perhaps, is the omission in most prior investigations (including those referenced above) of surface wave effects on the stability of ML fronts, which not only precludes the occurrence of Langmuir circulation (LC), a primary vertical mixing mechanism in the ocean surface boundary layer under wind forced seas ( Leibovich 1983 ; McWilliams et al. 1997 ; Thorpe 2004 ), but also the modification
structure of the vertical stratification and the development of the surface boundary layer. More significant, perhaps, is the omission in most prior investigations (including those referenced above) of surface wave effects on the stability of ML fronts, which not only precludes the occurrence of Langmuir circulation (LC), a primary vertical mixing mechanism in the ocean surface boundary layer under wind forced seas ( Leibovich 1983 ; McWilliams et al. 1997 ; Thorpe 2004 ), but also the modification
1. Introduction There is considerable evidence that the presence of Langmuir circulation (LC) fundamentally alters the dynamics of the surface boundary layer in the ocean ( Weller and Price 1988 ; Li and Garrett 1997 ; Kukulka et al. 2010 ; Belcher et al. 2012 ). Various mechanisms have been proposed for the formation of LC, but the most widely accepted explanation is that the wave-driven Stokes drift tilts vertical vorticity into the streamwise direction, leading to coherent vortices that
1. Introduction There is considerable evidence that the presence of Langmuir circulation (LC) fundamentally alters the dynamics of the surface boundary layer in the ocean ( Weller and Price 1988 ; Li and Garrett 1997 ; Kukulka et al. 2010 ; Belcher et al. 2012 ). Various mechanisms have been proposed for the formation of LC, but the most widely accepted explanation is that the wave-driven Stokes drift tilts vertical vorticity into the streamwise direction, leading to coherent vortices that
(1984c) , Farmer and Li (1995) , and Thorpe et al. (2003) —that bubble bands form within the downwelling regions produced by Langmuir circulation (hereinafter referred to as Lc). Zedel and Farmer (1991) demonstrate that the most intense and deepest-going bubble clouds appear within these bands, while Thorpe et al. (2003) show that the rate of dissipation of turbulent kinetic energy per unit mass ε is, on average, enhanced within the bands. There has, however, been no simultaneous measurements
(1984c) , Farmer and Li (1995) , and Thorpe et al. (2003) —that bubble bands form within the downwelling regions produced by Langmuir circulation (hereinafter referred to as Lc). Zedel and Farmer (1991) demonstrate that the most intense and deepest-going bubble clouds appear within these bands, while Thorpe et al. (2003) show that the rate of dissipation of turbulent kinetic energy per unit mass ε is, on average, enhanced within the bands. There has, however, been no simultaneous measurements
64 JOURNAL OF PHYSICAL OCEANOGRAPHY VOLUME25Is Langmuir Circulation Driven by Surface Waves or Surface Cooling? MING LI AND CHRIS GARRETTCentre for Earth and Ocean Research, University of Victoria, Victoria, British Columbia. Canada(Manuscript received 7 December 1993, in final form 6 May 1994) The ratio of the buoyancy force driving thermal convection to the surface wave vortex
64 JOURNAL OF PHYSICAL OCEANOGRAPHY VOLUME25Is Langmuir Circulation Driven by Surface Waves or Surface Cooling? MING LI AND CHRIS GARRETTCentre for Earth and Ocean Research, University of Victoria, Victoria, British Columbia. Canada(Manuscript received 7 December 1993, in final form 6 May 1994) The ratio of the buoyancy force driving thermal convection to the surface wave vortex
