Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation

• Published in: Nature
• Main Authors: Shakun, Jeremy D., Clark, Peter U., He, Feng, Marcott, Shaun A., Mix, Alan C., Liu, Zhengyu, Otto-Bliesner, Bette, Schmittner, Andreas, Bard, Edouard
• Other Authors: Shakun, JD (reprint author), Harvard Univ, Dept Earth & Planetary Sci, 20 Oxford St, Cambridge, MA 02138 USA., Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA., Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY 10964 USA., Oregon State Univ, Coll Earth Ocean & Atmospher Sci, Corvallis, OR 97331 USA., Univ Wisconsin, Ctr Climat Res, Madison, WI 53706 USA., Univ Wisconsin, Dept Atmospher & Ocean Sci, Madison, WI 53706 USA., Peking Univ, Lab Ocean Atmosphere Studies, Beijing 100871, Peoples R China., Natl Ctr Atmospher Res, Climate & Global Dynam Div, Boulder, CO 80307 USA., Univ Aix Marseille, CNRS, Coll France, CEREGE, F-13545 Aix En Provence, France., Harvard Univ, Dept Earth & Planetary Sci, 20 Oxford St, Cambridge, MA 02138 USA.
• Format: Journal/Newspaper
• Language: English
• Published: nature 2012
• Subjects: ATMOSPHERIC CO2 RISE; ICE CORE RECORDS; GLACIAL MAXIMUM; CLIMATE SENSITIVITY; SOUTHERN-HEMISPHERE; OCEAN; ATLANTIC; TEMPERATURE; CALIBRATION; GREENLAND; Antarctic; Greenland; Antarc*; ice core
• Online Access: https://hdl.handle.net/20.500.11897/393851; https://doi.org/10.1038/nature10915

The covariation of carbon dioxide (CO2) concentration and temperature in Antarctic ice-core records suggests a close link between CO2 and climate during the Pleistocene ice ages. The role and relative importance of CO2 in producing these climate changes remains unclear, however, in part because the ice-core deuterium record reflects local rather than global temperature. Here we construct a record of global surface temperature from 80 proxy records and show that temperature is correlated with and generally lags CO2 during the last (that is, the most recent) deglaciation. Differences between the respective temperature changes of the Northern Hemisphere and Southern Hemisphere parallel variations in the strength of the Atlantic meridional overturning circulation recorded in marine sediments. These observations, together with transient global climate model simulations, support the conclusion that an antiphased hemispheric temperature response to ocean circulation changes superimposed on globally in-phase warming driven by increasing CO2 concentrations is an explanation for much of the temperature change at the end of the most recent ice age. Multidisciplinary Sciences SCI(E) 0 ARTICLE 7392 49-+ 484