Martian dust storm impact on atmospheric H₂O and D/H observed by ExoMars Trace Gas Orbiter

Ann Carine Vandaele (1) , Daria Betsis (2) , Yuriy S. Ivanov (3) , Bojan Ristic (1) , Håkan Svedhem (4) , Jorge L. Vago (4) , José-Juan López-Moreno (5) , Giancarlo Bellucci (6) , Gustavo Alonso-Rodrigo (7) , Shohei Aoki (1) , Sophie Bauduin (8) , David Bolsée (1) , Giacomo Carrozzo (6) , R. Todd Clancy (9) , Edward Cloutis (10) , Matteo Crismani (11) , Frank Daerden (1) , Fabiana da Pieve (1) , Emiliano D’aversa (6) , Cédric Depiesse (1) , Justin T. Erwin (1) , Giuseppe Etiope (6) , Bernd Funke (5) , Didier Fussen (1) , Maia Garcia-Comas (5) , Anna Geminale (6) , Jean-Claude Gérard (12) , Marco Giuranna (6) , Leo Gkouvelis (12) , Francisco Gonzalez-Galindo (5) , James Holmes (13) , Benoît Hubert (12) , Nicolay I. Ignatiev (2) , Jacek Kaminski (14) , Özgür Karatekin (15) , David Kass (16) , Armin Kleinböhl (16) , Orietta Lanciano (17) , Stephen Lewis (13) , Giuliano Liuzzi (11) , Manuel López-Puertas (5) , Arnaud Mahieux (1) , Jon Mason (13) , Michael J. Mumma (11) , Hiromu Nakagawa (18) , Lori Neary (1) , Eddy Neefs (1) , Robert E. Novak (11) , Fabrizio Oliva (6) , Arianna Piccialli (1) , Etienne Renotte (19) , Birgit Ritter (12) , Séverine Robert (1) , Frédéric Schmidt (20) , Nick Schneider (21) , Giuseppe Sindoni (17) , Michael D. Smith (11) , Nicholas A. Teanby (22) , Ed Thiemann (21) , Alexander Trokhimovskiy (2) , Loic Trompet (1) , Jean Vander Auwera (23) , Geronimo Villanueva (11) , Sébastien Viscardy (1) , James Whiteway (24) , Yannick Willame (1) , Michael J. Wolff (9) , Paulina Wolkenberg (6) , Roger Yelle (25) , Juan Alday (26) , Francesca Altieri (6) , Konstantin Anufreychik (2) , Gabriele Arnold (27) , Lucio Baggio (28) , Denis A. Belyaev (2) , Jean-Loup Bertaux (28, 2) , Natalia Duxbury (29) , Anna A. Fedorova (2) , François Forget (30) , Thierry Fouchet (31) , Davide Grassi (6) , Alexey V. Grigoriev (2) , Sandrine Guerlet (30) , Paul Hartogh (32) , Nikolay I. Ignatiev (2) , Yasumasa Kasaba (18) , Igor Khatuntsev (2) , Nikita Kokonkov (2) , Oleg Korablev (2) , Vladimir Krasnopolsky (33) , Ruslan Kuzmin (2) , Gaetan Lacombe (28) , Franck Lefèvre (28) , Emmanuel Lellouch (31) , Miguel Lopez-Valverde (5) , Igor Maslov (2) , Mikhail Luginin (2) , Anni Määttänen (28) , Emmanuel Marcq (28) , Javier Martin-Torres (34) , Alexander Medvedev (32) , Ehouarn Millour (30) , Franck Montmessin (28) , Boris Moshkin (2) , Kevin Olsen (28) , Manish R. Patel (13) , Andrey Patrakeev (2) , Dmitry Patsaev (2) , Cathy Quantin-Nataf (35) , Daniel Rodionov (2) , Alexander Rodin (36) , Alexey Shakun (2) , Valery Shematovich (37) , Ian R. Thomas (1) , Nicolas Thomas (38) , Alexander Trokhimovsky (2) , Luis Vázquez (39) , Matthieu Vincendon (40) , Valérie Wilquet (1) , Colin F. Wilson (26) , Roland Young (30) , Ludmila Zasova (2) , Lev Zelenyi (2) , Maria Paz Zorzano (41)

1 BIRA-IASB - Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique
2 IKI - Space Research Institute of the Russian Academy of Sciences
3 MAO - Main Astronomical Observatory of NAS of Ukraine
4 ESTEC - European Space Research and Technology Centre
5 IAA - Instituto de Astrofísica de Andalucía
6 IAPS - Istituto di Astrofisica e Planetologia Spaziali - INAF
7 IDR - Instituto Universitario de Microgravedad "Ignacio Da Riva"
8 Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique
9 SSI - Space Science Institute [Boulder]
10 Department of Geography [Winnipeg]
11 GSFC - NASA Goddard Space Flight Center
12 LPAP - Laboratoire de Physique Atmosphérique et Planétaire
13 School of Physical Sciences [Milton Keynes]
14 Institute of Geophysics [Warsaw]
15 ROB - Royal Observatory of Belgium = Observatoire Royal de Belgique
16 JPL - Jet Propulsion Laboratory
17 ASI - Agenzia Spaziale Italiana
18 Graduate School of Information Sciences [Sendai]
19 AMOS - Advanced Mechanical and Optical Systems SA
20 GEOPS - Géosciences Paris Sud
21 LASP - Laboratory for Atmospheric and Space Physics [Boulder]
22 School of Earth Sciences [Bristol]
23 ULB - Université libre de Bruxelles
24 CRESS - Centre for Research in Earth and Space Science [Toronto]
25 LPL - Lunar and Planetary Laboratory [Tucson]
26 Department of Physics [Oxford]
27 DLR Institut für Planetenforschung
28 PLANETO - LATMOS
29 MSU - Lomonosov Moscow State University
30 LMD - Laboratoire de Météorologie Dynamique (UMR 8539)
31 LESIA (UMR_8109) - Laboratoire d'études spatiales et d'instrumentation en astrophysique
32 MPS - Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research
33 Institute for Astrophysics and Computational Sciences [Washington]
34 Department of Computer Science, Electrical and Space Engineering [Luleå]
35 LGL-TPE - Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement
36 MIPT - Moscow Institute of Physics and Technology [Moscow]
37 INASAN - Institute of Astronomy of the Russian Academy of Sciences
38 UNIBE - Universität Bern / University of Bern
39 UCM - Universidad Complutense de Madrid = Complutense University of Madrid [Madrid]
40 IAS - Institut d'astrophysique spatiale
41 CAB - Centro de Astrobiologia [Madrid]

Global dust storms on Mars are rare1,2 but can affect the Martian atmosphere for several months. They can cause changes in atmospheric dynamics and inflation of the atmosphere3, primarily owing to solar heating of the dust3. In turn, changes in atmospheric dynamics can affect the distribution of atmospheric water vapour, with potential implications for the atmospheric photochemistry and climate on Mars4. Recent observations of the water vapour abundance in the Martian atmosphere during dust storm conditions revealed a high-altitude increase in atmospheric water vapour that was more pronounced at high northern latitudes5,6, as well as a decrease in the water column at low latitudes7,8. Here we present concurrent, high-resolution measurements of dust, water and semiheavy water (HDO) at the onset of a global dust storm, obtained by the NOMAD and ACS instruments onboard the ExoMars Trace Gas Orbiter. We report the vertical distribution of the HDO/H2O ratio (D/H) from the planetary boundary layer up to an altitude of 80 kilometres. Our findings suggest that before the onset of the dust storm, HDO abundances were reduced to levels below detectability at altitudes above 40 kilometres. This decrease in HDO coincided with the presence of water-ice clouds. During the storm, an increase in the abundance of H2O and HDO was observed at altitudes between 40 and 80 kilometres. We propose that these increased abundances may be the result of warmer temperatures during the dust storm causing stronger atmospheric circulation and preventing ice cloud formation, which may confine water vapour to lower altitudes through gravitational fall and subsequent sublimation of ice crystals3. The observed changes in H2O and HDO abundance occurred within a few days during the development of the dust storm, suggesting a fast impact of dust storms on the Martian atmosphere.

Domaines: Astrophysique [astro-ph]

Ann Carine Vandaele, Daria Betsis, Yuriy S. Ivanov, Bojan Ristic, Håkan Svedhem, et al.. Martian dust storm impact on atmospheric H₂O and D/H observed by ExoMars Trace Gas Orbiter. Nature, 2019, 568, pp.521-525. ⟨10.1038/s41586-019-1097-3⟩. ⟨insu-02099160⟩