Contour plots of the models with different metallicities. The left, middle and right columns of the plot represent the models Z1, Z01, and Z001; the latter two exhibit 1/10 and 1/100 of the reference metallicity, respectively. The top, middle, and bottom rows correspond to the dust temperature, gas temperature, and the difference between the gas and dust temperature relative to the gas temperature. The decreasing metallicity leads to an increase in both dust and gas temperature but with the gas temperature increasing stronger (bottom row). The black dashed line represents the surface corresponding to a visual extinction of A_v = 1.