The lower atmosphere of Saturn’s moon Titan is strongly structured, with two distinct layers that affect wind patterns, dune spacing and cloud formation, reports a paper published online this week in Nature Geoscience. Benjamin Charnay and Sebastien Lebonnois used a three-dimensional climate model of Titan’s dense atmosphere (albeit without an active methane cycle) to study the layering in the moon’s lowermost atmosphere. Model simulations reconcile observations from the Huygens probe with independent and apparently incompatible measurements obtained by the Voyager 1 spacecraft, the Cassini orbiter, and dune spacing analyses.
In the simulations of Titan’s atmosphere, a shallow boundary layer of about 800 m depth develops on a daily scale, in addition to a 2-km-deep layer that is generated over a season. The authors conclude that in terms of its daily cycle, Titan is more similar to an Earth-like world than we thought.