THE THERMAL-STABILITY OF NEAR-SURFACE GROUND ICE ON MARS

THE existence of subsurface water ice on Mars has been predicted in several theoretical studies 1-5, but there are no definitive observations of its present distribution. Geomorphic features on the surface of Mars have been widely interpreted as evidence for the presence of ground ice 6-12, but many of these features are found at near-equatorial latitudes, where thermal models have predicted that near-surface water ice should not be stable under present climate conditions 3,13,14. Here I present the results of thermal calculations which show that observed geographic variations in the thermal and reflectance properties of martian soils significantly affect subsurface temperatures. My results indicate that in certain regions, ground-ice deposits could exist much closer to the surface, and much closer to the equator, than previously thought. In the future, these deposits could be a valuable resource for human exploration 15.