Aerosols and clouds in the limb of Mars: A study with the VMC camera onboard Mars Express

The Visual Monitoring Camera on board Mars Express provides images of varied resolutions, covering a wide range of locations and seasons, and has been taking images for several Martian Years. Some of these images show clear instances of aerosols layers in the limb of the planet, which allow studying their height and extension. Images close to pericenter display varying morphologies, and the extensive coverage by VMC allows determining inter-annual and areographicaI variations in occurrence.

The first years of the database were explored in Sánchez-Lavega (2018a), but this study was conditioned by the fact that there was no scientific programming of the observations until 2016. Nowadays, after several years of planning, a much more complete set of observations is available, covering four Martian years, with the added interest that a global dust storm developed in one of them (Sanchez-Lavega et al, 2018b). In this work, we will present results of a systematic analysis that aims to extend this study to MYs 33-37, measuring the extension and height of aerosols, their aerographic distribution and dependence on season and local time. We also contextualize our results using values of dust and water opacity retrieved by the Mars Climate Sounder onboard the Mars Reconnaissnce Orbiter and the estimates of the Mars Climate Database of the Laboratoire de Météorologie Dynamique.

References:

• Sánchez-Lavega, A. et al. “Limb clouds and dust on Mars from images obtained by the Visual Monitoring Camera (VMC) onboard Mars Express” ICARUS 299, 194-205 (2018a)
• Sánchez-Lavega, et al. “The Onset and Growth of the 2018 Martian Global Dust Storm” Geophysical Research Letters, 46, 6101-6108 (2018b)