Langmuir turbulence
In fluid dynamics, and oceanography, Langmuir turbulence is a turbulent flow with coherent Langmuir circulation structures that exist and evolve over a range of spatial and temporal scales.[1] These structures arise through an interaction between the ocean surface waves and the currents.
In the upper ocean Langmuir circulations are a special case where the turbulent structures exhibit a dominant cell size. In general it is expected that Langmuir turbulence is a global ocean phenomenon and not confined to gentle wind conditions or shallow water ways (as with most observations of Langmuir circulation).[2]
An important consequence of the Langmuir turbulence are deeply penetrating jets.[3] These features occur between counter-rotating Langmuir circulations and can inject turbulent kinetic energy to depths well below the depth scale for the surface waves (Stokes drift depth scale). [4] Langmuir turbulence could have an important impact on our understanding of climate.[2] In particular, Langmuir turbulence could affect the global ocean's sea surface temperature as the deeply penetrating Langmuir jets modify the depth of the ocean mixed layer.
See also
Notes
- McWilliams, J.; Sullivan, P.; Moeng, C. (1997), "Langmuir turbulence in the ocean", Journal of Fluid Mechanics, 334: 1–30, doi:10.1017/S0022112096004375
- Belcher, S.E.; Grant, A.L.M.; Hanley, K.E.; Fox-Kemper, B.; Van Roekel, L.; Sullivan, P.P.; Large, W.G.; Brown, A.; Hines, A.; Calvert, Daley; Rutgersson, Anna; Pettersson, Heidi; Bidlot, Jean-Raymond; Janssen, Peter A. E. M.; Polton, Jeff A. (2012), "A global perspective on Langmuir turbulence in the ocean surface boundary layer" (PDF), Geophysical Research Letters, 39 (18), doi:10.1029/2012GL052932
- Polton, J.A.; Belcher, S.E. (2007), "Langmuir Turbulence and deeply penetrating jets in an unstratified mixed layer", Journal of Geophysical Research, 112 (C9): 1–11, doi:10.1029/2007JC004205
- Sinha, N.; Tejada-Martinez, A.E.; Akan, C.; Grosch, C.E. (2015), "Toward a K-Profile Parameterization of Langmuir Turbulence in Shallow Coastal Shelves", Journal of Physical Oceanography, 45 (12): 2869–2895, doi:10.1175/JPO-D-14-0158.1