Maps of horizontal divergence div_h and circulation velocity v^ac for the average supergranule outflow regions at various solar latitudes (after correction for geometrical center-to-limb systematics). The maps were derived from HMI intensity images and Dopplergrams. The horizontal divergence div_h was computed from LCT v_x and v_y horizontal velocity maps. The LCT v^ac maps were obtained by averaging the tangential velocity component v_t over an annulus with radius 10 Mm and half-width 2 Mm to resemble the τ^ac measurement geometry (Fig. 1d). For TD, the v^ac maps are based on τ^ac travel-time maps (Fig. 1b) that were computed from Dopplergrams.