Hα profiles after PCA decomposition for two regions with persistent upflows (left) and downflows (right) in excess of ±3 km s⁻¹ (see online movie with an animated sequence of profiles). The locations are indicated in Fig. 4 by colored plus signs (+) and crosses (×). The color bar at the bottom uses the same color scheme to track the temporal evolution of the spectral line profiles. The black line corresponds to the quiet-Sun profile in both panels.