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09:06
Removal of Exogenous Materials from the Outer Portion of Frozen Cores to Investigate the Ancient Biological Communities Harbored Inside
Published on: July 3, 2016
The deep ocean during the last interglacial period.
J C Duplessy1, D M Roche, M Kageyama
1Laboratoire des Sciences du Climat et de l'Environnement/Institut Pierre Simon Laplace (LSCE/IPSL), CNRS/Université de Versailles Saint Quentin (CEA/CNRS/UVSQ), Parc du CNRS, 91198 Gif sur Yvette, France. Jean-Claude.Duplessy@lsce.cnrs-gif.fr
Science (New York, N.Y.)
|April 7, 2007
Summary
During the last interglacial period, North Atlantic Deep Water (NADW) was warmer. This ocean warming, driven by insolation, may have contributed to melting the West Antarctic Ice Sheet.
Area of Science:
- Paleoceanography
- Climate Science
- Oceanography
Background:
- Deep ocean temperatures provide crucial insights into past climate dynamics.
- Understanding past interglacial periods helps predict future climate change.
- North Atlantic Deep Water (NADW) and Antarctic Bottom Water (AABW) are key components of global ocean circulation.
Purpose of the Study:
- To reconstruct deep ocean temperatures during the last interglacial period.
- To investigate the drivers of observed deep ocean temperature changes.
- To assess the potential impact of these temperature changes on Antarctic ice sheets.
Main Methods:
- Oxygen isotope analysis of benthic foraminifera from deep-sea cores.
- Analysis of cores from the Atlantic and Southern Oceans.
- Ocean model simulations to test hypotheses.
Main Results:
- North Atlantic Deep Water (NADW) was 0.4°C warmer during the last interglacial period compared to present day.
- Antarctic Bottom Water (AABW) temperatures remained unchanged.
- Model simulations indicate high-latitude insolation as the forcing mechanism for NADW warming.
Conclusions:
- Ocean warming, particularly in the North Atlantic, was driven by changes in insolation.
- Warming of NADW likely transferred heat to the Southern Ocean.
- This heat transfer may have contributed to the partial melting of the West Antarctic Ice Sheet during the last interglacial period.
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