About the Permian Paleoclimate Atlas
This electronic atlas takes advantage of the internet to present a wide range of new paleoclimate data and model results for the Permian. This medium allows great flexibility and interactivity, and in particular, allows the presentation of a wide and comprehensive range of material, far beyond what paper publishing would allow. Initially, only information for the Wordian stage (268 Ma) is shown.
The Permian Period contains the most recent transition from a major glaciation to a fully ice-free state, a transition that has been ascribed to an increase in atmospheric CO2. Intriguingly, this deglaciation was relatively rapid, being mainly confined to the Sakmarian stage (Early Permian). A new set of paleogeographic maps has been compiled for the Permian that include the most detailed reconstructions of paleotopography produced for any pre-Quaternary interval. These maps have been used as boundary conditions for a suite of experiments with the GENESIS (version 2) GCM. Experiments reported here were conducted for the Sakmarian and Wordian paleogeographies, with varied levels of atmospheric CO2. Our goals were to: (1) evaluate how differences in paleogeography between the two stages is manifested in the data and model results; (2) investigate the effects of incorporating extensive lakes in southern Gondwanan, shown to be important in previous experiments; and (3) investigate the potential for ice-sheet initiation: was high CO2 responsible for keeping the late Sakmarian and the Wordian ice-free? Predictions made by the model are tested against new global compilations of independent data derived from the geological record.