Carbon Cycling and Habitability of Massive Earth-like Exoplanets

As the number of detected rocky extrasolar planets increases, question whether their surfaces could be habitable is becoming more pertinent. On Earth, long-term carbonate silicate cycle able to regulate surface temperatures over timescales larger than one million years. Elevated enhance weathering, removing CO$_2$ from atmosphere, which subducted into mantle. At mid-ocean ridges, supplied atmosphere interior. The carbon degassing flux controlled by melting depth beneath ridges and spreading rate, influenced pressure- temperature-dependent mantle viscosity. influences temperature pressure on become increasingly important for massive planets. Here, we couple a thermal evolution model Earth-like different masses with assess evolution. We find that rate at 4.5 Gyr increases planetary mass up 3 $M_\oplus$, since temperature-dependence viscosity dominates its pressure-dependency. For higher planets, pressure-dependence plates slow down. In addition, effective as function has maximum $M_\oplus$. Altogether, Gyr, therefore have This work emphasizes both age should considered when predicting habitability exoplanets. Despite these effects, remains an mechanism regulates