Photochemical kinetics uncertainties in modeling Titan’s atmosphere: A review

This paper is a review dealing with the photochemistry of Titan’s atmosphere and its sources of uncertainties. It presents current knowledge on the active photochemistry occurring in Titan’s atmosphere. A brief discussion of major dissociation paths and essential chemical reactions is given, which allows us to emphasize on the photochemical processes that are still not well represented in the models and might thus be contributing mostly to the overall imprecision of theoretical results. We present a method to evaluate uncertainty factors of the chemical rate constants at temperatures representative of Titan’s atmosphere. This compilation can be used as a reference for future uncertainty propagation analysis in Titan’s photochemical models developed in the frame of the Cassini–Huygens mission.