Temporal evolution of temperature and CO–CH₄ volume mixing ratios in a 1-bar atmosphere around GJ 1132b considering two end-member oxygen fugacities (IW-3 and IW+3). We assumed K_zz = 10⁷ cm²/s. The initial atmospheric composition was set by the outgassing model and is shown with the blue curve corresponding to t=0 s. We consider fo₂ = IW-3 and A_c = 10⁻² for the low oxygen fugacity end-member (left panels) and fo₂ = IW+3 and A_c = 10⁻⁶ for the high oxygen fugacity end-member (right panels). The dashed black curve shows the prediction of chemical equilibrium without vertical mixing computed with FastChem using the initial state of the atmosphere (abundances set by outgassing).