Temporal evolution of the two consecutive upflow events. The sequence of the Hα −0.77 Å images of the ROI during the two upflow events is shown in panels a1–16. The 2 Mm slit (a)–b) in panel a1 indicates the cut location used for the space-time slice image shown in Fig. 5. The arrow in panel a13 denotes a top left spiral arm, which encounters a neighboring bright point indicated with a red cross in the same panel. The locations of the cotemporal IRIS slit are indicated with two vertical dotted lines on several panels, which are used for the investigation of the IRIS Mg II k spectrum in Figs. 6 and 7. The outlines of the vortical structures in some of panels a1–a16 during the first and second events are overplotted with different colored contours in panels b) and c), respectively.