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Updated: Jul 20, 2026
08:16
Ice Generation and the Heat and Mass Transfer Phenomena of Introducing Water to a Cold Bath of Brine
Published on: March 13, 2017
An oceanic cold reversal during the last deglaciation
B Stenni1, V Masson-Delmotte, S Johnsen
1Department of Geological, Environmental and Marine Sciences, University of Trieste, Trieste, Italy. stenni@univ.trieste.it
Science (New York, N.Y.)
|September 15, 2001
Summary
An Antarctic ice core shows sea surface temperatures shifted 800 years after the Antarctic Cold Reversal, linked to atmospheric circulation changes. This reveals oceanic cold reversals in the southern Indian Ocean.
Area of Science:
- Paleoclimatology
- Glaciology
- Oceanography
Background:
- Ice cores provide invaluable archives of past climate conditions.
- Deuterium excess in ice cores is a proxy for moisture source temperature and atmospheric water vapor characteristics.
- The European Project for Ice Coring in Antarctica (EPICA) Dome C ice core offers a high-resolution record of Antarctic climate history.
Purpose of the Study:
- To reconstruct sea surface temperature (SST) changes in Southern Ocean moisture source regions.
- To determine the timing and magnitude of climate events during the last deglaciation using ice core data.
- To investigate the relationship between oceanic temperature gradients and atmospheric circulation strength.
Main Methods:
- Detailed analysis of the deuterium excess profile from the Dome C EPICA ice core.
- Correlation of deuterium excess data with other paleoclimate proxies (e.g., sodium concentration).
- Inference of past sea surface temperatures and atmospheric circulation patterns.
Main Results:
- A distinct Oceanic Cold Reversal was identified in the southern Indian Ocean, occurring approximately 800 years after the Antarctic Cold Reversal.
- The deuterium excess profile indicates significant shifts in sea surface temperatures of the precipitation source regions for Dome C.
- A strong correlation was observed between the temperature gradient (oceanic moisture source to Antarctica) and the Dome C sodium profile, mirroring atmospheric circulation strength during deglaciation.
Conclusions:
- The study confirms a lagged oceanic response to glacial-interglacial climate transitions.
- The findings highlight the critical role of the temperature gradient between oceanic moisture sources and Antarctica in driving atmospheric circulation patterns.
- Deuterium excess in Antarctic ice cores is a powerful tool for understanding past ocean-atmosphere dynamics.
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