HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

Revealing a High Water Abundance in the Upper Mesosphere of Mars With ACS Onboard TGO

Abstract : We present the first water vapor profiles encompassing the upper mesosphere of Mars, 100–120 km, far exceeding the maximum altitudes where remote sensing has been able to observe water to date. Our results are based on solar occultation measurements by Atmospheric Chemistry Suite (ACS) onboard the ExoMars Trace Gas Orbiter (TGO). The observed wavelength range around 2.7 μm possesses strong CO2 and H2O absorption lines allowing sensitive temperature and density retrievals. We report a maximum H2O mixing ratio varying from 10 to 50 ppmv at 100–120 km during the global dust storm (GDS) of Martian Year (MY) 34 and around southern summer solstice of MY 34 and 35. During other seasons water remains persistently below ∼2 ppmv. We claim that contributions of the MY34 GDS and perihelion periods into the projected hydrogen escape from Mars are nearly equivalent.
Document type :
Journal articles
Complete list of metadata

Contributor : Catherine Cardon Connect in order to contact the contributor
Submitted on : Wednesday, May 26, 2021 - 4:50:52 PM
Last modification on : Friday, April 1, 2022 - 3:50:50 AM
Long-term archiving on: : Friday, August 27, 2021 - 8:34:32 PM


Files produced by the author(s)



Denis Belyaev, Anna Fedorova, Alexander Trokhimovskiy, Juan Alday, Franck Montmessin, et al.. Revealing a High Water Abundance in the Upper Mesosphere of Mars With ACS Onboard TGO. Geophysical Research Letters, American Geophysical Union, 2021, 48 (10), pp.e2021GL093411. ⟨10.1029/2021GL093411⟩. ⟨insu-03237572⟩



Record views


Files downloads