Contours in the mid-plane of total heating (left column), viscous heating (middle column), and Ohmic heating (right column), at t = 200 (top row), t = 400 (middle row), and t = 700 (bottom row). The total heating in the plane in each plot (in dimensions ) is (a) 8.81 × 10⁻³, (b) 4.30 × 10⁻³, (c) 4.52 × 10⁻³, (d) 1.50 × 10⁻³, (e) 1.10 × 10⁻³, (f) 4.05 × 10⁻⁴, (g) 2.99 × 10⁻³, (h) 2.24 × 10⁻³, and (i) 7.51 × 10⁻⁴. Colours are found with the same logarithmic scale as was used in Fig. 7. Although, numerically, heating is recorded outside the shaded regions below the minimum of 10⁻⁶ on the colour bar, it is here set in white.