A systematic study of \ce{CO2} planetary atmospheres and their link to the stellar environment

TL;DR

This study uses a 1D radiative transfer model to analyze CO2 atmospheres, exploring their properties and variability, which aids understanding exoplanet atmospheres and potential habitability.

Contribution

It introduces a computationally efficient 1D model for simulating CO2 atmospheres and applies it to a large synthetic dataset to study atmospheric profiles.

Findings

Pressure and thermal profiles vary with parameters.

The model provides insights despite limitations compared to 3D models.

It enables large-scale parameter studies of exoplanet atmospheres.

Abstract

The Milky Way Galaxy is literally teeming with exoplanets; thousands of planets have been discovered, with thousands more planet candidates identified. Terrestrial-like planets are quite common around other stars, and are expected to be detected in large numbers in the future. Such planets are the primary targets in the search for potentially habitable conditions outside the solar system. Determining the atmospheric composition of exoplanets is mandatory to understand their origin and evolution, as atmospheric processes play crucial roles in many aspects of planetary architecture. In this work we construct and exploit a 1D radiative transfer model based on the discrete-ordinates method in plane-parallel geometry. Radiative results are linked to a convective flux that redistributes energy at any altitude producing atmospheric profiles in radiative-convective equilibrium. The model has been applied to a large number (6250) of closely dry synthetic \ce{CO2} atmospheres, and the resulting pressure and thermal profiles have been interpreted in terms of parameter variability. Although less accurate than 3D general circulation models, not properly accounting for e.g., clouds and atmospheric and ocean dynamics, 1D descriptions are computationally inexpensive and retain significant value by allowing multidimensional parameter sweeps with relative ease.