4 ± 1.5 °C abrupt warming 11,270 yr ago identified from trapped air in Greenland ice

• Published in: Earth and Planetary Science Letters
• Main Authors: Kobashi, Takuro, Severinghaus, J. P., Barnola, Jean-Marc
• Other Authors: Scripps Institution of Oceanography (SIO), University of California San Diego (UC San Diego), University of California-University of California, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS), NSF grants OPP 05-38657 and ATM 99-05241
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: Preboreal Oscillation; abrupt climate change; Holocene; Greenland; ice core; [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology; Greenland ice core
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-00378493; https://doi.org/10.1016/j.epsl.2008.01.032

International audience Nitrogen and argon isotopes in air trapped in a Greenland ice core (GISP2) show two prominent peaks in the interval 11,800–10,800 B.P., which indicate two large abrupt warming events. The first abrupt warming (10 ± 4 °C) is the widely documented event at the end of the Younger Dryas. Here, we report on the second abrupt warming (4 ± 1.5 °C), which occurred at the end of a short lived cooler interval known as the Preboreal Oscillation (11,270 ± 30 B.P.). A rapid snow accumulation increase suggests that the climatic transition may have occurred within a few years. The character of the Preboreal Oscillation and the subsequent abrupt warming is similar to the Dansgaard–Oeschger (D/O) events in the last glacial period, suggestive of a common mechanism, but different from another large climate change at 8,200 B.P., in which cooling was abrupt but subsequent warming was gradual. The large abrupt warming at 11,270 B.P. may be considered to be the final D/O event prior to the arrival of the present stable and warm epoch.