GCM simulations of Snowball Earth conditions during the late Proterozoic

Gregory S. Jenkins, Steven R. Smith

Research output: Contribution to journalArticle

53 Citations (Scopus)

Abstract

In order to simulate the Snowball Earth conditions that may have existed during the late Proterozoic we have conducted a series of GCM simulations using a simple 50-meter slab ocean, a reduced solar constant of 6% and varied CO2 concentrations. In this study, we vary the CO2 concentration from 100 to 3400-ppmv and use rotation rates corresponding to 18 and 24-hour day-lengths. We also examine the effects of increasing the poleward transport of heat by the oceans. Our results show that below a critical value of approximately 1700 ppmv of atmospheric CO2, sea-ice and sub-freezing temperatures occur from the poles to the Equator. A global mean annual two meter air temperature of 221°K is found for boundary conditions of 100 ppmv atmospheric CO2, 6% reduction in solar forcing and . a rotation rate corresponding to an 18 hour day. These results confirm those of earlier studies suggesting or implying that low-latitude glaciation occurred during the late Proterozoic. However, since the ocean is the critical factor for low-latitude glaciation, the results should be view cautiously because of the simple slab-ocean used in this study.

Original languageEnglish (US)
Article number1999GL900538
Pages (from-to)2263-2266
Number of pages4
JournalGeophysical Research Letters
Volume26
Issue number15
DOIs
StatePublished - Aug 1 1999

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general circulation model
Proterozoic
oceans
ocean
tropical regions
simulation
glaciation
slab
slabs
solar constant
day length
sea ice
equators
freezing
poles
boundary condition
air temperature
boundary conditions
heat
temperature

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Earth and Planetary Sciences(all)

Cite this

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GCM simulations of Snowball Earth conditions during the late Proterozoic. / Jenkins, Gregory S.; Smith, Steven R.

In: Geophysical Research Letters, Vol. 26, No. 15, 1999GL900538, 01.08.1999, p. 2263-2266.

Research output: Contribution to journalArticle

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