Modeling late Paleozoic glaciation

Journal Article · Mon Jun 01 04:00:00 EDT 1992 · Geology; (United States)

DOI:https://doi.org/10.1130/0091-7613(1992)020<0507:MLPG>2.3.CO;2· OSTI ID:6952068

Crowley, T J; Baum, S K ^[1]

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1. Applied Research Corp., College Station, TX (United States)

Late Paleozoic glaciation on Gondwana is associated with changes in geography, solar luminosity, and estimated CO{sub 2} levels. To assess the relative importance of these boundary conditions, the authors conducted a suite of climate model simulations for the periods before, during, and after peak mid-Carboniferous ({approximately}300 Ma) glaciation (340, 300, and 255 and 225 Ma, respectively). Orbital insolation values favorable for glaciation and interglaciation were used for each time interval. Results indicate that changes in geography cause significant changes in snow area, but the temporal trend is not consistent with the geologic record for glaciation. Combined CO{sub 2}-plus-geography changes yield the best agreement with observations. In addition, interglacial orbital configurations result in almost ice-free conditions for the glacial interval at 300 Ma, at a time of low CO{sub 2}. The large simulated glacial-interglacial snowline fluctuations for Permian-Carboniferous time may explain cyclothem fluctuations at these times. Overall, results support the importance of the CO{sub 2} paradigm, but also indicate that a fuller understanding of past climate change requires consideration of paleogeographic, luminosity, and orbital insolation changes.

• OSTI ID: 6952068
• Journal Information: Geology; (United States), Journal Name: Geology; (United States) Vol. 20:6; ISSN GLGYB; ISSN 0091-7613
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
ATMOSPHERIC CHEMISTRY
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBONIFEROUS PERIOD
CHALCOGENIDES
CHEMISTRY
CLIMATE MODELS
EARTH PLANET
GEOCHEMISTRY
GEOLOGIC AGES
GLACIERS
ICE
ICE CAPS
MATHEMATICAL MODELS
OXIDES
OXYGEN COMPOUNDS
PALEOCLIMATOLOGY
PALEONTOLOGY
PALEOZOIC ERA
PERMIAN PERIOD
PLANETS