Figure 11:

Mixing ratio profiles for several species (as labelled) in Saturn’s atmosphere for a model that includes a source of H₂O flowing in at the top of the atmosphere from a local source such as Enceladus, and a cometary source from an impact that occurred 400 years ago, along with a background injection rate of 6.7 × 10⁴ CO molecules cm⁻² s⁻¹ and 7.2 × 10³ H₂O molecules cm⁻² s⁻¹ from the ablation of icy grains.