LExEn: Evolution of Climate on Terrestrial Planets: Exploring the Limits of Habitability

Southwest Research Institute, San Antonio TX

Investigators

Abstract

0085378 Grinspoon Dr. David Grinspoon and colleagues at the Southwest Research Institute are developing a program of modeling the evolution of planet climates that will lead to a greater understanding of the stability of climates against geologically induced episodes of climate change. It will help to define the range of planetary size, composition and location that can lead to stable, habitable environments on terrestrial-type planets in the universe. A systems approach has been applied to studying the climate of Venus which simulates the interactions between interior, surface, atmosphere and clouds. Several improvements will be made to this model which will turn it into a powerful tool for studying the general problem of climate evolution on terrestrial planets. These improvements include: 1) A detailed cloud microphysical model to more accurately simulate cloud responses to changes in atmospheric composition. 2) A simulation of the runaway or moist greenhouse effect, including cloud feedbacks, that will help us refine the inner edge of the habitable zone. 3) A modification of the model to simulate the climate evolution of Mars as a function of geological activity on that planet. 4) The incorporation of models of the thermal and volcanic evolution of terrestrial planets to parameterize outgassing histories as a function of planetary size. This will allow the modeling of climate evolution on a suite of hypothetical terrestrial planets as a function of size and stellar-centric distance. This project is funded through the Division of Astronomical Sciences for the NSF's Life in Extreme Environments program. ***