(top panels) and (bottom panels) as a function of s/L for different times. s is the curvilinear coordinate of the poloidal field line in which max(B_ϕ/B_p) is reached, and L the length of this field line. s = 0 locates the inner radius and s = L the equator. The simulation is the same as in Fig. 3 with the exception of L_u = 10⁴. The vertical dashed line indicates s_max the location of max(B_ϕ/B_p) on the poloidal field line.