MuSICA-V · Multi-Scale Investigation of the Chemistry of the Atmosphere of Venus

Multi-Scale Investigation of the Chemistry of the Atmosphere of Venus

Venus is the closest planet to Earth. Despite a similar size and mass, there are differences between the two planets. At the surface, the temperature can reach 730 K with pressure of 90 bar, and a composition of 96 % of carbon dioxide. Venus hosts a global cloud layer between 45 and 70 km of altitude, with composition and temperature-pressure conditions close to the Earth's stratosphere and complex chemistry with both sulphur and water cycle. This global cloud layer plays a key role in the radiative equilibrium of the atmosphere. Therefore, it is fundamental to study its composition and dynamics at all spatio-temporal scales to understand the atmosphere of Venus. Despite decades of measurements and modelling, there are still many unknowns about the chemistry of the Venusian atmosphere. The Project MuSICA-V (Multi-Scale Investigation of the Chemistry of the Atmosphere of Venus) conducted at LATMOS will develop new and ambitious numerical models using a hierarchy of models: a Planetary Climate Model (PCM), mesoscale and Large-Eddy Simulation (LES) models all coupled to a photochemistry scheme. These three models are performed with different resolutions and would help capture the spatio-temporal variability of the chemistry over different scales as never before, and will increase the understanding of the coupling of the dynamics and chemistry from the large-scale to the small-scales. The proposed effort is perfectly timed and relevant to ongoing and planned international Venus exploration activities: ESA mission EnVision, and NASA missions DAVINCI and VERITAS, were all three selected to launch in the next decade. The main objectives of these missions are to study the surface and the dynamics both inside and below the clouds. The project will simulate predictions for chemistry variabilities to produce observables for past and future missions, to improve the interpretation of the measurements. The MuSICA-V project is built around four scientific axes. The first three axes relate to the development of numerical tools with a hierarchy of models, and the last one pertains to the new analyses of the Venus Express data and helping future missions in chemistry predictions of their observables. The MuSICA-V project will allow me to acquire broad expertise in the science of Venus and clouds, increasing my knowledge of atmospheric numerical simulations, as well as bringing me new expertise in modelling atmospheric chemistry and spectroscopic remote-sensing targeting different altitudes and scientific objectives and directly linked to a space mission. Chemistry is one of the main focuses of the future selected Venus missions, to constrain the possible active volcanism, and to study the surface/atmosphere interaction and the coupling of the dynamics and the chemistry. The project MuSICA-V will develop new tools to investigate the chemistry of Venus. The chemistry of the Venusian atmosphere was almost exclusively studied with 1D models and not often in 3D. The Venusian tropospheric chemistry was never modelled in 3D. The impact of atmospheric turbulence on chemistry has never been studied. The models developed with the MuSICA-V project will give an unprecedented insight into the Venus atmospheric chemistry from the surface to cloud-top altitude, and from the small to large-scale, will be a useful tool for the planetary science community. The models developed during this project could be then used to assess the feasibility of future missions. With a better knowledge of Venus' current state, the species abundance in the atmosphere, and their reservoir buffered in the surface rocks, it would be possible to understand the evolution of Venus and to know why the climates of Earth and Venus are so different. The characterization of the present-day Venus climate also has an interest in the context of habitability. With current telescopes, distinguishing an exo-Earth planet from an exo-Venus is challenging. The understanding of the coupling of the dynamics with chemistry and clouds would increase the capacity to differentiate between the two types of climate.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз