Norbert Schorghofer of NAI’s University of Hawai’i Team has a new paper in this week’s Nature describing a climate model he developed which accounts for the advance and retreat of the subsurface martian ice layers. The model reveals forty major ice ages over the past five million years, and explains the present distribution of subsurface ice on Mars. His findings outline expectations of ice stratigraphy at the NASA Mars Phoenix Mission’s landing site.