Comparison of the vector components (B_x, B_y, B_z) of the magnetic field. First row: HMI observation of the leading sunspot of active region NOAA 11072 (2010.05.25 03:00:00 TAI), which serves as the reference for our sunspot model. Second and third rows: model with and without temporal fluctuations, respectively. Every column is plotted on the same scale in units of Gauss displayed by the color bar at the top of the column.