Molar ratio of H₂O relative to all ices (the sum of all volatile species, including H₂O) for one particular simulation (Σ₀ = 95.844 g cm^-2, a_core = 46, γ = 0.9) as a function of the distance to the star, and for non-irradiated (black lines) and irradiated (grey lines) models, both with (dashed lines) and without (solid lines) clathrates, including chemical variation (CO:CO₂ molar ratio).