Observations of CO2 clouds on Mars from TIRVIM and NIR solar occultation measurements onboard TGO

Mikhail Luginin (1) , Nikolay Ignatiev (1) , Anna Fedorova (1) , Alexander Trokhimovskiy (1) , Alexey Grigoriev (1, 2) , Alexey Shakun (1) , Franck Montmessin (3) , Oleg Korablev (1)

1 IKI - Space Research Institute of the Russian Academy of Sciences
2 ANU - Australian National University
3 PLANETO - LATMOS

Carbon dioxide is the major constituent of the Martian atmosphere. Its seasonal cycle plays an important role in atmospheric dynamics and climate. Formation of the polar CO2 frost deposits results in up to 30% of atmospheric pressure variations as well as in dramatic change in surface reflectance and emissivity. Another case of carbon dioxide condensation is formation of a CO2 clouds that are still poorly studied, despite the fact that they have been observed by a number of instruments [1−6] on the orbit of Mars. In this work, we will present first results of CO2 clouds observations from a combination of thermal-infrared (1.7−17 µm) and near-infrared (0.7-1.6 µm) spectra measured by TIRVIM and NIR instruments onboard the ExoMars Trace Gas Orbiter (TGO) in solar occultation geometry. These instruments are part of the Atmospheric Chemistry Suite (ACS), a set of three spectrometers (NIR, MIR, and TIRVIM) that is conducting scientific measurements on the orbit of Mars since the spring of 2018 [7].

Domains: Sciences of the Universe [physics]

Mikhail Luginin, Nikolay Ignatiev, Anna Fedorova, Alexander Trokhimovskiy, Alexey Grigoriev, et al.. Observations of CO2 clouds on Mars from TIRVIM and NIR solar occultation measurements onboard TGO. EGU General Assembly 2021, Apr 2021, Online Meeting, Germany. pp.EGU21-12721, ⟨10.5194/egusphere-egu21-12721⟩. ⟨insu-03196491⟩