Martian Mesospheric CO2 Ice Clouds in a 1D-Model
Résumé
Since the first probable observation of a CO2 mesospheric cloud on Mars [1] their formation - out of the main component of the atmosphere (95%) - has not been fully addressed yet by studies dealing with CO2 ice cloud modeling in general (e.g [2][15]). Their formation process may be constrained by various recent observations from which effective sizes of crystals have been derived ([8][10][11][14]). Moreover, temperatures far below the CO2 condensation point have been revealed by the SPICAM instrument in the mesosphere, suggesting a strong potential for triggering CO2 ice condensation in extremely supersaturated environment ([3][10]). Mesoscale modeling has shown that locations where gravity waves are able to propagate through the martian atmosphere up to the mesosphere are strongly correlated with locations of CO2 ice cloud observations [13]. These elements strongly suggest an interesting way to model the formation of CO2 mesospheric clouds within a 1D-model, by creating highly supersatured cold pockets with the help of gravity waves.