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 language | English (US) |
|---|---|
| Article number | 1999GL900538 |
| Pages (from-to) | 2263-2266 |
| Number of pages | 4 |
| Journal | Geophysical Research Letters |
| Volume | 26 |
| Issue number | 15 |
| DOIs | |
| State | Published - Aug 1 1999 |
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All Science Journal Classification (ASJC) codes
- Geophysics
- Earth and Planetary Sciences(all)
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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 journal › Article
TY - JOUR
T1 - GCM simulations of Snowball Earth conditions during the late Proterozoic
AU - Jenkins, Gregory S.
AU - Smith, Steven R.
PY - 1999/8/1
Y1 - 1999/8/1
N2 - 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.
AB - 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.
UR - http://www.scopus.com/inward/record.url?scp=0033431768&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033431768&partnerID=8YFLogxK
U2 - 10.1029/1999GL900538
DO - 10.1029/1999GL900538
M3 - Article
VL - 26
SP - 2263
EP - 2266
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 15
M1 - 1999GL900538
ER -