The Sun's Reversing Flows and Heat Spike as Caused by g-Modes

The reversing east-west flows centered near 0.675 R_☉ have not been explained by gravity waves from the convection zone because suitable wavelengths do not penetrate deeply enough to drive the observed flow. An alternative is explored using g-modes, many of whose rotation rates have already been detected. Simple formulas for the radial drift of the flow and for angular momentum transfer from asymptotic g-modes are expressed in terms of local oscillation amplitudes and dissipation rates. The main loss mechanism is horizontal turbulence caused by the flow. It exceeds that due to gravity waves for which Schatzman estimated a diffusivity ~10⁸ m² s^-1. Our proposed flow has a peak zonal speed of 50 m s^-1, consistent with the observations at current resolving power. An array of g-modes with amplitudes near the detectable limit at the solar surface can cause the flow to replace itself about every 1.3 yr, as observed, if there are ~10³ high harmonic modes. Since the flow occupies the same thin layer where the sound speed is anomalous, heat dissipated in driving the flow acts to reduce that solar modeling error.