Send to

Choose Destination
Science. 2012 May 11;336(6082):711-4. doi: 10.1126/science.1217161. Epub 2012 Mar 29.

Carbon isotope constraints on the deglacial CO₂ rise from ice cores.

Author information

Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, University of Bern, CH-3012 Bern, Switzerland.


The stable carbon isotope ratio of atmospheric CO(2) (δ(13)C(atm)) is a key parameter in deciphering past carbon cycle changes. Here we present δ(13)C(atm) data for the past 24,000 years derived from three independent records from two Antarctic ice cores. We conclude that a pronounced 0.3 per mil decrease in δ(13)C(atm) during the early deglaciation can be best explained by upwelling of old, carbon-enriched waters in the Southern Ocean. Later in the deglaciation, regrowth of the terrestrial biosphere, changes in sea surface temperature, and ocean circulation governed the δ(13)C(atm) evolution. During the Last Glacial Maximum, δ(13)C(atm) and atmospheric CO(2) concentration were essentially constant, which suggests that the carbon cycle was in dynamic equilibrium and that the net transfer of carbon to the deep ocean had occurred before then.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center