Numerical simulations of gravity wave driven shear flows in the solar tachocline

Numerical simulations of gravity wave driven shear flows in the solar radiative interior are presented. A suite of models varying wavenumber, frequency, amplitude and diffusivities is run. In general, the shear flows that develop grow to angular velocities which are greater than or equivalent to the horizontal phase speed of the wave; thus forming a critical level. Critical levels are not allowed, and their dynamics are not accounted for, in typical asymptotic treatments of wave-driven oscillations. This may pose problems for theories based on such treatments.