a) Temporal evolution of the Poynting flux. Solid lines show the emergence term, F_emergence, and dashed lines show the shearing term, F_shear. b) The unsigned magnetic flux Φ_xy. c) The axial flux for the bipole’s center in the positive y-direction (bipole AB) (solid). Dashed lines stand for the axial flux of λ = 10. d) Flux difference ΔΦ_xz. The dashed vertical line indicates then beginning of the undulation of the PIL and the dotted vertical lines indicate the times of the onset of high-speed jets from the interface.