ROCKE-3D: A DYNAMICAL MODELING APPROACH TO EXPLORING ROCKY PLANET HABITABILITY

Current planetary missions are designed to collect data on a suite of diverse planetary characteristics such as surficial mineralogy, sedimentary layering, atmospheric composition, and even the presence of subsurface oceans. These data provide tantalizing clues about possible past and current habitable spaces in our Solar System. However, determining the existence, distribution and persistence over time of potentially habitable spaces on a given world remains a significant challenge.

The challenges faced in reconstructing the habitability state(s) of other terrestrial rocky bodies are often similar to those confronted by deep-time Earth paleoclimatologists, who also grapple with sparse proxy data in their efforts to reconstruct past global and regional environments. Fortunately, three-dimensional general circulation models (GCMs) can be adapted to simulate non-modern Earth conditions, helping to “fill in” information gaps resulting from sparse data, providing new information on atmosphere/ocean dynamical processes often not preserved in the geologic record, and to suggest new hypotheses testable by future field and/or remote observing missions.

The ROCKE-3D (Resolving Orbital and Climate Keys of Earth and Extraterrestrial Environments with Dynamics) GCM, a generalized version of the NASA GISS GCM, is being developed specifically to explore the climate of rocky terrestrial planets with geophysical and atmospheric properties unlike modern Earth. Here we present some examples of ROCKE-3D simulations of deep-time Earth paleoclimates, from Snowball Earths to the Cretaceous Hothouse. These experiments represent some of ROCKE-3D’s capabilities in simulating known habitable (and inhabited) settings as an illustration of this tool’s potential to assist planetary habitability studies here in the Solar System, and for rocky exoplanets yet to be discovered.