Temporal evolution of a retraction event seen in the retraction simulations. From top to bottom: vertical component of the magnetic field B_z at z₂ = −0.60 Mm, temperature at z₂, divergence of the velocity ∇ ⋅ v at z₂, vertical component of the velocity v_z at z₂ (v_z < 0 are upflows), and the v_x component of the velocity at z = z₂. The arrows in the first row show the horizontal magnetic field (B_x, B_y) on the z = z₂ plane. The length of the arrows are proportional to . Likewise, arrows in the fifth row show the horizontal velocity field (v_x, v_y) with the length being proportional to . Black and white contours enclose to regions where T(z₂) > 5250 K.