First gray-scale intensity image of the time series overplotted with the actual (left) and smoothed CO⁵BOLD plasma velocity vectors at log τ =  +1 (see left most panel in Fig. 10 for the corresponding LCT flow vectors). The flow field was smoothed using a Gaussian kernel with an FWHM = 686 km (see Fig. 15) corresponding to the maximum correlation coefficient between plasma and LCT (time cadence Δt = 60 s and Gaussian sampling window with an FWHM = 1200 km) velocities. The speed and direction of the flow field are given by rainbow-colored arrows, where dark blue corresponds to low and red to high velocities within the range of 0.75–7.5 km s^-1 and 0.3–3.0 km s^-1 for the actual and smoothed flow fields, respectively. The time-dependent CO⁵BOLD flow fields are shown in Movie 2, which is provided in the electronic edition.