Characterization of the Martian mesosphere with NOMAD/TGO observations and a Global Climate Model
- 1Instituto de Astrofísica de Andalucía-CSIC, Sistema Solar, Granada, Spain (ggalindo@iaa.es)
- 2Laboratoire de Météorologie Dynamique, IPSL, Paris, France
- 3LATMOS, IPSL, Paris, France
- 4Open University, Milton Keynes, UK
- 5INAF-IAPS, Italy
- 6Belgian Institute for Space Aeronomy, Brussels, Belgium
The Martian mesosphere, and in particular the upper mesosphere, above about 80 km from the surface, remains poorly explored in comparison with the troposphere and the thermosphere/ionosphere. Observations by the NOMAD and ACS instruments on board the ExoMars Trace Gas Orbiter mission (TGO in what follows) are starting to fill this gap by providing measurements such as the abundance of mesospheric water and the effects of global dust storms (Vandaele et al., 2019; Belyaev et al., 2021; Brines et al., 2022), the CO variability (Modak et al., 2022) or the temperature and density structure (López-Valverde et al., 2022). For the first time we have a set of diverse atmospheric parameters derived simultaneously with good vertical resolution and from a single instrument, which is ideal for model validation purposes.
In this work, we will compare the predictions of the LMD-Mars GCM (LMD-MGCM) in the mesosphere with the NOMAD results (abundances of CO2, CO, and H2O, as well as temperature) obtained by the retrieval scheme developed at the Instituto de Astrofisica de Andalucia-CSIC (IAA), in order to validate the model and to gain insight into the physical processes at the origin of the observed structures. In particular, we will focus on the comparison of the CO2 density and temperature structure observed below ~120 km (López-Valverde et al., 2022) during the second half of Mars Year 34, a period including the MY34 global dust storm. We will show that the model reproduces well the strong seasonal variations of the CO2 density observed by NOMAD. However, the model tends to overestimate the temperatures above ~50 km.
Acknowledgments
F.G-G. is funded by the Spanish Ministerio de Ciencia, Innovación y Universidades, the Agencia Estatal de Investigación and EC FEDER funds under project RTI2018-100920-J-I00. MALV, AB, AM, and AS were supported by grant PGC2018-101836-B-100 (MCIU/AEI/FEDER, EU). The IAA team acknowledges financial support from the State Agency for Research of the Spanish MCIU through the “Center of Excellence Severo Ochoa" award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709)
How to cite: González-Galindo, F., López-Valverde, M. Á., Brines, A., Modak, A., Stolzenbach, A., Funke, B., López-Moreno, J. J., Forget, F., Millour, E., Lefèvre, F., Vals, M., Montmessin, F., Patel, M., Bellucci, G., and Vandaele, A.-C.: Characterization of the Martian mesosphere with NOMAD/TGO observations and a Global Climate Model, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-701, https://doi.org/10.5194/epsc2022-701, 2022.
