1. The current trend of global warming is pushing Earth back from its Ice Age "icehouse" conditions—with large ice sheets and many glaciers—to a "greenhouse" with little ice overall, Barker noted.

2. Prothero, From Greenhouse to Icehouse: The Marine Eocene-Oligocene Transition: Accessory benthic foraminiferal events reported by Berggren and Miller (1989) to occur in the late Eocene are the migrations into the Bathyal

3. The Carboniferous, spanning 60 Ma, was an important period in Earth history, with major changes in atmospheric composition (in terms of both oxygen and carbon dioxide), the development of an icehouse world, the formation of vast tropical peat (coal) deposits, and the radiation of …