Vertical slices showing the flows from Runs A0 (left) and A100 (right). Note that the box is deeper in the latter case. The colour contours indicate the vertical velocity, u_z. The tilde refers to normalisation by $\sqrt{\mathit{dg}}$. The arrows map streamlines where the linewidth reflects the flow speed. The blue and red curves indicate the superadiabatic temperature gradient, Δ∇, with negative (positive) values in blue (red). The boundaries of different zones as defined in Table 1 are indicated by the corresponding labels and orange dotted lines.