A modelling of the non-LTE populations of the main infrared emitters between 1 and 20 μm in the Titan's atmosphere has been carried out and the results are presented. The model runs from the surface of the planet up to 1270 km in 1 km steps and incorporates the statistical equilibrium equations for the vibrational levels of the main emitters in the infrared and solves the radiative transfer equations for the main rotationvibration bands of CH_4, C_2H_2, and C_2H_6. The populations have been obtained by solving the system composed by these equations. Absorption of solar radiation infrared radiation in the near-infrared bands of CH_4 and subsequent cascading to the ν_4 band of CH_4 has been considered. The work is oriented to assess the potential impact of non- LTE effects on the remote sensing of these gases. The model developed for this purpose include a complete set of radiative and collisional processes. In order to cover typical and extreme remote sensing scenarios, the models have been applied to different atmospheric and solar illumination conditions. Also a study of the dependence of the results on the uncertainties of the parameters of the model has been performed.
|Publication status||Published - 1 Jan 2002|