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arXiv · 2610.05287

Irradiated Atmospheres VII. Effect of Mixing Energy Flux on Atmosphere-Interior Coupling}

Wei Zhong·Zhen-Tai Zhang·Mei Ting Mark·Xiang-Xing Chen·Bo Ma·Xian-Yu Tan·Cong Yu·Dong-dong Ni
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Abstract

Highly irradiated, underdense rocky planets such as puffy Venuses may host strong coupling between their atmospheres and magma-ocean interiors. Previous studies have mainly treated this coupling through radiative transfer and chemical equilibrium, leaving the role of vertical mixing unclear. Here we quantify how energy transport associated with vertical mixing modifies the thermal structure, volatile chemistry, and emission spectra of puffy Venuses. Atmospheric circulation and gravity-wave breaking are possible dynamical sources of such transport. We show that this energy transport provides an additional greenhouse-like heating pathway by warming the deep atmosphere, thereby increasing the pressure and temperature at the magma-ocean surface. The resulting thermal changes also reshape the atmospheric composition, especially the abundances of \ce{CO} and \ce{H2O}, and change the partitioning of C-, H-, and O-bearing volatiles between the atmosphere and the magma ocean. Moreover, these changes reshape the mid-infrared planet--star flux ratio, especially at low equilibrium temperatures and in higher-mass planets. Under high C/O, it slightly increases the flux near $3.5$--$4.0\,μ$m, but more broadly reduces atmospheric transparency and suppresses the flux. This may affect radius estimates for puffy Venuses over a limited temperature range.

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Wei Zhong, Zhen-Tai Zhang, Mei Ting Mark, Xiang-Xing Chen, Bo Ma, Xian-Yu Tan, Cong Yu, Dong-dong Ni. 2026-10-04. Irradiated Atmospheres VII. Effect of Mixing Energy Flux on Atmosphere-Interior Coupling}. https://arxiv.org/abs/2610.05287

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