Stormy water on Mars: The distribution and saturation of atmospheric water during the dusty season

Anna Fedorova (1) , Franck Montmessin (2) , Oleg Korablev (1) , Mikhail Luginin (1) , Alexander Trokhimovskiy (1) , Denis A. Belyaev (1) , Nikolay I. Ignatiev (1) , Franck Lefèvre (2) , Juan Alday (3) , Patrick G. J. Irwin (3) , Kevin Olsen (2, 3) , Jean-Loup Bertaux (2) , Ehouarn Millour (4) , Anni Määttänen (2) , Alexey Shakun (1) , Alexey V. Grigoriev (1) , Andrey Patrakeev (1) , Svyatoslav Korsa (1) , Nikita Kokonkov (1) , Lucio Baggio (2) , Francois Forget (4) , Colin F. Wilson (3)

1 IKI - Space Research Institute of the Russian Academy of Sciences
2 PLANETO - LATMOS
3 Department of Physics [Oxford]
4 LMD - Laboratoire de Météorologie Dynamique (UMR 8539)

The loss of water from Mars to space is thought to result from the transport of water to the upper atmosphere, where it is dissociated to hydrogen and escapes the planet. Recent observations have suggested large, rapid seasonal intrusions of water into the upper atmosphere, boosting the hydrogen abundance. We use the Atmospheric Chemistry Suite on the ExoMars Trace Gas Orbiter to characterize the water distribution by altitude. Water profiles during the 2018–2019 southern spring and summer stormy seasons show that high-altitude water is preferentially supplied close to perihelion, and supersaturation occurs even when clouds are present. This implies that the potential for water to escape from Mars is higher than previously thought.

Domains: Sciences of the Universe [physics]

Anna Fedorova, Franck Montmessin, Oleg Korablev, Mikhail Luginin, Alexander Trokhimovskiy, et al.. Stormy water on Mars: The distribution and saturation of atmospheric water during the dusty season. Science, 2020, 367 (6475), pp.297-300. ⟨10.1126/science.aay9522⟩. ⟨insu-02440376⟩