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Exploring the Effects of Atmospheric Forcings on Evaporation: Experimental Integration of the Atmospheric Boundary Layer and Shallow Subsurface
Published on: June 8, 2015
Ice sheet and solid Earth influences on far-field sea-level histories
Sophie E Bassett1, Glenn A Milne, Jerry X Mitrovica
1Department of Earth Sciences, University of Durham, Durham DH1 3LE, UK.
Science (New York, N.Y.)
|June 25, 2005
Summary
Sea-level change models during the last glacial period had discrepancies. A new model incorporating high-viscosity lower mantle and Antarctic ice sheet meltwater resolves these issues, supporting early Antarctic deglaciation as a climate driver.
Area of Science:
- Earth Science
- Paleoclimatology
- Glaciology
Background:
- Sea-level change predictions after the last glacial maximum show discrepancies.
- Observations from Tahiti, Huon Peninsula, and Sunda Shelf during Lateglacial time (14,000–9,000 years BP) conflict with previous models.
Purpose of the Study:
- To resolve discrepancies in Lateglacial sea-level change predictions.
- To investigate the role of glacial isostatic adjustment and Antarctic ice sheet meltwater in sea-level changes.
Main Methods:
- Developed a glacial isostatic adjustment model.
- Incorporated a high-viscosity lower mantle (4 x 10^22 Pa s).
- Included a significant contribution from Antarctic ice sheet meltwater pulse IA (~15 meters eustatic equivalent).
Main Results:
- The model successfully resolved discrepancies between predicted and observed sea-level changes.
- High lower mantle viscosity and substantial Antarctic meltwater were key factors.
- The findings align with theories of early and rapid Antarctic deglaciation.
Conclusions:
- An early and rapid Antarctic deglaciation played a crucial role in ending the last glacial period.
- Glacial isostatic adjustment, influenced by mantle viscosity and ice sheet dynamics, is critical for accurate sea-level predictions.
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