Constructed RM_IGM maps [rad/m²] for three PMF models studied in this work at z = 2 redshift depth. The left part of the figure depicts the mean ⟨RM_IGM⟩ distribution in Galactic coordinates with 10 000 and ∼3300 light-cone realisations in the uniform, and km1 and k25 cases, respectively (in the latter cases a smaller number of realisations was chosen for a better visualisation). The right part shows example 2D light-cone maps (with 2° FOVs and 20″ image resolution) used for calculating RM_IGM statistics.