Greenland temperature response to climate forcing during the last deglaciation

• Published in: Science
• Main Authors: Buizert, Christo, Gkinis, Vasileios, Severinghaus, Jeffrey P., He, Feng, Lecavalier, Benoit S., Kindler, Philippe, Leuenberger, Markus, Carlson, Anders E., Vinther, Bo, Masson-Delmotte, Valerie, White, James W. C., Liu, Zhengyu, Otto-Bliesner, Bette, Brook, Edward J.
• Other Authors: Buizert, C (reprint author), Oregon State Univ, Coll Earth Ocean & Atmospher Sci, Corvallis, OR 97331 USA., Oregon State Univ, Coll Earth Ocean & Atmospher Sci, Corvallis, OR 97331 USA., Univ Copenhagen, Niels Bohr Inst, Ctr Ice & Climate, DK-1168 Copenhagen, Denmark., Univ Colorado, Inst Arctic & Alpine Res, Boulder, CO 80309 USA., Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA., Univ Wisconsin, Nelson Inst Environm Studies, Ctr Climat Res, Madison, WI 53706 USA., Mem Univ Newfoundland, Dept Phys & Phys Oceanog, St John, NF, Canada., Univ Bern, Inst Phys, Div Climate & Environm Phys, Bern, Switzerland., Univ Bern, Oeschger Ctr Climate Change Res, Bern, Switzerland., Inst Pierre Simon Laplace UMR CEA CNRS UVSQ 8212, Lab Sci Climat & Environm, Gif Sur Yvette, France., Peking Univ, Lab Climate & Ocean Atmosphere Studies, Beijing 100871, Peoples R China., Natl Ctr Atmospher Res, Climate & Global Dynam Div, Boulder, CO 80307 USA.
• Format: Journal/Newspaper
• Language: English
• Published: science 2014
• Subjects: ICE CORE; GLACIAL TERMINATION; TRAPPED AIR; POLAR ICE; SEASONALITY; ACCUMULATION; CIRCULATION; SENSITIVITY; ANTARCTICA; DIFFUSION; Greenland; Antarc*; Antarctica; Greenland ice core; ice core; North Atlantic
• Online Access: https://hdl.handle.net/20.500.11897/342239; https://doi.org/10.1126/science.1254961

Greenland ice core water isotopic composition (delta O-18) provides detailed evidence for abrupt climate changes but is by itself insufficient for quantitative reconstruction of past temperatures and their spatial patterns. We investigate Greenland temperature evolution during the last deglaciation using independent reconstructions from three ice cores and simulations with a coupled ocean-atmosphere climate model. Contrary to the traditional delta O-18 interpretation, the Younger Dryas period was 4.5 degrees +/- 2 degrees C warmer than the Oldest Dryas, due to increased carbon dioxide forcing and summer insolation. The magnitude of abrupt temperature changes is larger in central Greenland (9 degrees to 14 degrees C) than in the northwest (5 degrees to 9 degrees C), fingerprinting a North Atlantic origin. Simulated changes in temperature seasonality closely track changes in the Atlantic overturning strength and support the hypothesis that abrupt climate change is mostly a winter phenomenon. Multidisciplinary Sciences SCI(E) PubMed 7 ARTICLE [e-mail] 6201 1177-1180 345