Europlanet Science Congress 2020
Virtual meeting
21 September – 9 October 2020
Europlanet Science Congress 2020
Virtual meeting
21 September – 9 October 2020
EPSC Abstracts
Vol.14, EPSC2020-53, 2020, updated on 08 Oct 2020
https://doi.org/10.5194/epsc2020-53
Europlanet Science Congress 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Chemistry and dynamics in the atmospheres of the Ice Giants: from the troposphere to the ionosphere

Thibault Cavalié1,2, Michel Dobrijevic1, Vincent Hue3, and Jérémy Leconte1
Thibault Cavalié et al.
  • 1LAB – CNRS – Univ. Bordeaux, Pessac, France
  • 2LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, France
  • 3Southwest Research Institute, San Antonio, USA

Uranus and Neptune have only been visited by one spacecraft, Voyager 2. Their atmospheres thus remain mysterious in terms of composition and dynamics, despite repeated efforts to observe them from the ground and earth-orbiting telescopes. Deep composition is key to constrain internal and formation processes but is difficult to measure with remote sensing techniques because of the condensation into various cloud layers of several key volatiles. Chemical complexification initiated by solar UV and magnetospheric electrons, as well as contamination by external sources (dust, comets, ring and satellite material), all occurring in the upper atmosphere but diffusing downward, can further complicate the situation because of the mixing of these various components caused by dynamics.

In this context, an atmospheric entry probe to measure key volatiles (e.g. noble gases, C, N, S, P) in the upper troposphere is highly desirable (Mousis et al. 2018, Cavalié et al. 2020) and would benefit from direct observational support from an orbiting spacecraft (Fletcher et al. 2020), as well as contextual ground-based supporting observations. All these measurements are essential to constrain the chemistry models we develop to better understand the composition and dynamics in the Ice Giant atmospheres. With a coherent set of models, ranging from 1D thermochemical and diffusion models for the tropospheres (Cavalié et al. 2017, Leconte et al. 2017, Venot et al. 2019, 2020) to 2D time-dependent photochemical models for the stratospheres and ionospheres (Hue et al. 2018, Dobrijevic et al. 2020), we aim at contributing to a better understanding of the Ice Giant composition and dynamics.

How to cite: Cavalié, T., Dobrijevic, M., Hue, V., and Leconte, J.: Chemistry and dynamics in the atmospheres of the Ice Giants: from the troposphere to the ionosphere, Europlanet Science Congress 2020, online, 21 September–9 Oct 2020, EPSC2020-53, https://doi.org/10.5194/epsc2020-53, 2020