Phanerozoic paleogeography and its impact on long-term climatic change and habitability

Paleogeography is a key boundary condition for reconstructing Earth’s climatic evolution and habitability. On geological timescales, paleogeographic changes control the latitudinal positioning of environments, governing received and reflected solar radiation and climatic zonation. The distribution and morphology of continents and oceans further control ocean–atmosphere circulation and influence the evolution and dispersal of marine and terrestrial biota.

Here we present a new effort to construct a continuous (1 Myr resolution) global paleogeographic digital elevation model for the entire Phanerozoic (540–0 Ma). The reconstructions integrate new and previously published plate models, and global and regional paleo-elevation datasets. Building on and extending methodologies previously applied to the Cenozoic (66–0 Ma), our approach incorporates dynamic topography from mantle circulation (100–0 Ma), oceanic lithospheric ages, sediment thickness, detailed continental margin evolution, parameterized subduction zones, and spatiotemporal interpolation between topographic datasets of different time intervals. The reconstructions focus in detail on key paleogeographic features relevant for ocean circulation, climate, and biogeography, including oceanic gateways, land bridges, and large-scale orogenies.

Finally, we present results from a variety of fully coupled Earth system model experiments, mainly with Cenozoic paleogeographic boundary conditions (e.g., present, Eocene–Oligocene, Late Eocene, and the DeepMIP Early Eocene ensemble), to demonstrate how paleogeographic changes influences planetary energy budgets, ocean circulation, and climate sensitivity. These results highlight systematic relationships that offer potential for extrapolation throughout the Phanerozoic.