Left: time-averaged radial profile of rms velocity in four low-resolution simulations that exclude the near-surface layers but include a different extent of the radiative zone. Right: time-averaged radial profile of rms velocity in simulations Low7 and Low8, that include the near-surface layers up to the surface at r/R = 1.0. The shaded areas indicate one standard deviation above and below the time-averaged lines; in the left panel the shaded area for simulation Low2 is shown. A heavy vertical black line marks the boundary between the radiative and convection zones, calculated from the radial profile of entropy produced by the one-dimensional stellar evolution calculation and the Schwarzschild criterion. Gray vertical lines mark the inner radial boundary of the spherical-shell simulation volume for each simulation shown.