Numerical Simulations of an Asymptotically Reduced Model of Anisotropic Langmuir Turbulence

``Langmuir turbulence'' is a wind and surface-wave driven flow that is thought to dominate vertical transport and mixing in the ocean surface boundary layer. The characteristic occurrence of quasi-coherent counter-rotating vortical structures elongated in the wind direction renders Langmuir turbulence strongly anisotropic. Recently, an asymptotically exact reduced model of this flow was derived using multiscale analysis (Chini, Julien \& Knobloch, GAFD 2009). The reduced PDEs go beyond strictly 2D (downwind invariant) formulations of the governing Craik--Leibovich (CL) equations by consistently incorporating the dominant 3D physical processes while continuing to average or filter certain fast, fine downwind-scale flow features. Here, pseudospectral numerical simulations of the reduced PDEs are performed to explore the dynamics and bifurcation structure of the reduced model.