Comparison of selected 2D output variables for the DALI fiducial model (left column) and the same DALI model with no inner dust disk within 30 au (right column), as described in Section 5.2.1. First row: dust temperature; second row: gas temperature; third row CO gas abundance; fourth row: UV flux in ISM units. Bottom row: Comparison of the gas temperature at the τ = 1 surface for the ¹²CO, ¹³CO, and C¹⁸O lines; the blue shaded region indicates the CO freeze-out temperature range. The τ = 1 surface for the ¹²CO, ¹³CO, and C¹⁸O is overlaid as solid, dashed, and dotted lines, respectively.