Horizontally averaged field components and EMFs as a function of z. Solid curves correspond to sg-mhd-tau20, and dashed curves correspond to MRI-compare. The first two images depict ℰ_x, and ℰ_y, respectively. Images three and four show the magnetic field components B_x and B_y, respectively. The red curves were averaged over the 200 − 400 interval of sg-mhd-tau20, and the blue profiles over the 800 − 1300 interval. The time samples were evaluated every 2. The dashed curves correspond to MRI-compare and were averaged over the 100 − 1000 interval, with time samples every 1. All components change signs, and some even oscillate over time. Hence, a special time-averaging technique, , was applied to all shown profiles, f(z). Thereby, each quantity is multiplied by the momentary sign of ⟨B_y⟩_xy(z, t) before the time average is applied.