Significance of Langmuir circulation in upper ocean mixing: Comparison of observations and simulations

Representing upper ocean turbulence accurately in models remains a great challenge for improving weather and climate projections. Langmuir circulation (LC) is a turbulent process driven by wind and surface waves that plays a key role in transferring momentum, heat, and mass in the oceanic surface layer. We present a direct comparison between observations and large eddy simulations, based on the wave-averaged Navier-Stokes equation, of an LC growth event. The evolution of cross-wind velocity variance and spatial scales, as well as mixed layer deepening are only consistent with simulations if LC effects are included in the model. Our results offer a validation of the large eddy simulation approach to understanding LC dynamics, and demonstrate the importance of LC in ocean surface layer mixing. Citation: Kukulka, T., A. J. Plueddemann, J. H. Trowbridge, and P. P. Sullivan (2009), Significance of Langmuir circulation in upper ocean mixing: Comparison of observations and simulations, Geophys. Res. Lett., 36, L10603, doi: 10.1029/2009GL037620.