Atmospheric CO 2 and Climate on Millennial Time Scales During the Last Glacial Period
Reconstructions of ancient atmospheric carbon dioxide (CO 2 ) variations help us better understand how the global carbon cycle and climate are linked. We compared CO 2 variations on millennial time scales between 20,000 and 90,000 years ago with an Antarctic temperature proxy and records of abrupt c...
Published in: | Science |
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Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
American Association for the Advancement of Science (AAAS)
2008
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Subjects: | |
Online Access: | http://dx.doi.org/10.1126/science.1160832 https://www.science.org/doi/pdf/10.1126/science.1160832 |
Summary: | Reconstructions of ancient atmospheric carbon dioxide (CO 2 ) variations help us better understand how the global carbon cycle and climate are linked. We compared CO 2 variations on millennial time scales between 20,000 and 90,000 years ago with an Antarctic temperature proxy and records of abrupt climate change in the Northern Hemisphere. CO 2 concentration and Antarctic temperature were positively correlated over millennial-scale climate cycles, implying a strong connection to Southern Ocean processes. Evidence from marine sediment proxies indicates that CO 2 concentration rose most rapidly when North Atlantic Deep Water shoaled and stratification in the Southern Ocean was reduced. These increases in CO 2 concentration occurred during stadial (cold) periods in the Northern Hemisphere, several thousand years before abrupt warming events in Greenland. |
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