Evolution of the pore area with (black + symbols). Blue △ symbols connected by the dashed line show the total positive magnetic flux (Φ) in the pore. Red Λ symbols connected by the dash-doted line show Φ in the penumbra. The horizontal blue lines at the top of the plot indicate the times of G-band observations, where the light blue correspond to the imaging cadence of 60 s. The vertical red lines correspond to the times of SP scans and the vertical black lines labelled a)–f) show the times of images shown in Figs. 1, 3, and 4.