Late Paleozoic tropical climate response to Gondwanan deglaciation

Coupled climate-biome model simulations of the late Paleozoic were developed to determine the response of Pangean tropical climate to Gondwanan deglaciation. The model simulations predict substantial changes over equatorial Pangea including continental drying, a reversal of equatorial winds, warming, heavier δ 18 O values of meteoric precipitation, and the expansion of deserts and the contraction of forests. The magnitude of these tropical responses is sensi- tive to the extent of Gondwana continental ice and the deglacial rise in atmospheric pCO 2 , boundary conditions that are not well known for the late Paleozoic. Nonetheless the model predictions are consistent with climatic and environmental trends determined from terrestrial proxy data, implying that the deglaciation of Gondwana was a transformational climate event in tropical Pangea.

[1]  Sandy P. Harrison,et al.  Climate and CO2 controls on global vegetation distribution at the last glacial maximum: analysis based on palaeovegetation data, biome modelling and palaeoclimate simulations , 2003 .

[2]  G. Soreghan,et al.  Equatorial Aridity in Western Pangea: Lower Permian Loessite and Dolomitic Paleosols in Northeastern New Mexico, U.S.A. , 2001 .

[3]  S. Baum,et al.  Climate model comparison of Gondwanan and Laurentide glaciations , 1991 .

[4]  D. Pollard,et al.  Siberian glaciation as a constraint on Permian–Carboniferous CO2 levels , 2006 .

[5]  D. Royer.  CO2-forced climate thresholds during the Phanerozoic , 2006 .

[6]  J. Kutzbach,et al.  Simulated warm polar currents during the middle Permian , 2002 .

[7]  C. Cleal,et al.  Palaeozoic tropical rainforests and their effect on global climates: is the past the key to the present? , 2005 .

[8]  C. Fielding,et al.  Sedimentological record of the late Paleozoic glaciation in Queensland, Australia , 2004 .

[9]  D. Pollard,et al.  Simulation of stable water isotope variations by the GENESIS GCM for modern conditions , 2002 .

[10]  R. Gastaldo,et al.  Out of the Icehouse into the Greenhouse: A Late Paleozoic Analogue for Modern Global Vegetational Change , 1996 .

[11]  W. Peltier,et al.  The Pangean ice age: studies with a coupled climate-ice sheet model , 1999 .

[12]  F. T. Dulong,et al.  Climate Controls on the Stratigraphy of a Middle Pennsylvanian Cyclothem in North America , 2003 .

[13]  I. Montañez,et al.  Morphology and distribution of fossil soils in the Permo‐Pennsylvanian Wichita and Bowie Groups, north‐central Texas, USA: implications for western equatorial Pangean palaeoclimate during icehouse–greenhouse transition , 2004 .

[14]  R. Stouffer,et al.  Response of the ITCZ to Northern Hemisphere cooling , 2006 .

[15]  L. Babcock,et al.  Reevaluation of the timing and extent of late Paleozoic glaciation in Gondwana: Role of the Transantarctic Mountains , 2003 .

[16]  David Pollard,et al.  Greenland and Antarctic Mass Balances for Present and Doubled Atmospheric CO2 from the GENESIS Version-2 Global Climate Model , 1997 .

[17]  P. Bitter,et al.  Constraints on Pennsylvanian glacioeustatic sea-level changes using oxygen isotopes of conodont apatite , 2006 .

[18]  D. Pollard,et al.  General circulation model simulation of the δ18O content of continental precipitation in the middle Cretaceous: A model-proxy comparison , 2007 .

[19]  S. Baum,et al.  Modeling late Paleozoic glaciation , 1992 .

[20]  J. Arkani‐Hamed,et al.  Stress differences in the Martian lithosphere: Constraints on the thermal state of Mars , 2002 .

[21]  Michael A. Hamilton,et al.  Paleowinds inferred from detrital-zircon geochronology of upper Paleozoic loessite, western equatorial Pangea , 2002 .

[22]  R. Gastaldo,et al.  Response Of Late Carboniferous And Early Permian Plant Communities To Climate Change , 2001 .

[23]  B. Otto‐Bliesner.  The Role of Mountains, Polar Ice, and Vegetation in Determining the Tropical Climate During the Middle Pennsylvanian: Climate Model Simulations , 2003 .

[24]  A. Ziegler.  Phytogeographic patterns and continental configurations during the Permian Period , 1990, Geological Society, London, Memoirs.

[25]  C. Scotese,et al.  Carboniferous paleogeographic, phytogeographic, and paleoclimatic reconstructions , 1985 .

[26]  Isabel P. Montañez,et al.  Shifts in late Paleozoic atmospheric circulation over western equatorial Pangea: Insights from pedogenic mineral δ18O compositions , 2002 .

[27]  C. B. Cecil,et al.  Climate Controls on Stratigraphy , 2003 .

[28]  Michael C. Rygel,et al.  CO2-Forced Climate and Vegetation Instability During Late Paleozoic Deglaciation , 2007, Science.

[29]  J. Kutzbach,et al.  Simulations of Permian Climate and Comparisons with Climate‐Sensitive Sediments , 2002, The Journal of Geology.

[30]  G. Ramstein,et al.  The Late Permian climate. What can be inferred from climate modelling concerning Pangea scenarios and Hercynian range altitude , 2001 .

[31]  I. C. Prentice,et al.  BIOME3: An equilibrium terrestrial biosphere model based on ecophysiological constraints, resource availability, and competition among plant functional types , 1996 .

[32]  I. Montañez,et al.  Oxygen and hydrogen isotope compositions of Permian pedogenic phyllosilicates: Development of modern surface domain arrays and implications for paleotemperature reconstructions , 2005 .