Investigating the influence of the supercontinent cycle on planetary habitability

During Earth’s last supercontinent phase, Pangea, both the surface—including continental location, topography, and clustering—and its climate were markedly different from today. At least for its early tenure (End Permian, ~252 Ma), geological evidence indicates a greenhouse climate with elevated pCO₂, minimal polar ice, and an arid continental interior. It is predicted that, within the next 200–300 million years, our planet will once again transition into a new supercontinent phase. Given the gradual increase in solar irradiance as the Sun ages coupled with the substantial reorientation of continents, it is likely that the future supercontinent will experience a climate substantially different from the present.

Building upon previous results, we apply a novel metric of habitability which incorporates conditions for both temperature and water availability and has additionally been validated against the observed distribution of surface life on present day Earth. We first repeat the validation for a 'baseline' present day simulation to verify the ROCKE-3D model and metric validity at a coarse-scale resolution. This is followed by a comparison of the model-predicted surface habitability of Pangea (~252 Ma) against a set of lithological indicators, which we then use to inform upon the impact of future continental configuration and topography upon climate and habitability. Specifically, we investigate how Earth's capacity to support both complex and microbial life—both on land and within the upper ocean—may differ as continents assemble and fragment, offering insights into the evolution of habitability on a tectonically active planet over geological timescales.