Irradiated Atmospheres. II. Interplay between Scattering and Vertical-mixing-induced Energy Transport

Abstract

Scattering is crucial for the atmospheric thermal profiles. The energy transport by vertical mixing plays an essential role in the greenhouse or anti-greenhouse effect. This work explores the interaction between scattering and vertical mixing, specifically whether these processes enhance or mitigate each other’s effects on atmospheric temperature. The interaction between mixing flux and scattering is nonlinear. Our calculations indicate that thermal scattering intensifies the greenhouse effects caused by vertical mixing in the middle atmosphere but reduces them in the lower layers. In the middle atmosphere, increased vertical mixing enhances the warming effect of thermal scattering while diminishing the cooling effect of visible scattering. In the lower atmosphere, it enhances the anti-greenhouse effect linked to visible scattering and diminishes the greenhouse effect produced by thermal scattering. The combined influence of thermal scattering and vertical mixing on the lower atmosphere’s greenhouse effect is weaker than their separate impacts, akin to 1 + 1 < 2. It is also interesting to note that the joint effect may also influence chemistry and cloud formation, altering the thermal structure.

Keywords

• Exoplanet atmospheres
• Radiative transfer equation
• Radiative transfer simulations
• Atmospheric structure