The WAIS Divide deep ice core WD2014 chronology - Part 2: Annual-layer counting (0-31 ka BP)

• Main Authors: Sigl, Michael, Fudge, Tyler, Winstrup, Mai, Cole-Dai, Jihong, Ferris, David, Mcconnell, Joseph, Taylor, Ken, Welten, Kees, Woodruff, Thomas, Adolphi, Florian, Bisiaux, Marion, Brook, Edward, Buizert, Christo, Caffee, Marc, Dunbar, Nelia, Edwards, Ross, Geng, Lei, Iverson, Nels, Koffman, Bess, Layman, Lawrence, Maselli, Olivia, Mcgwire, Kenneth, Muscheler, Raimund, Nishiizumi, Kunihiko, Pasteris, Daniel, Rhodes, Rachael, Sowers, Todd
• Other Authors: Paul Scherrer Institute (PSI), Desert Research Institute (DRI), University of Washington Seattle, Department of Chemistry and Biochemistry Brookings, South Dakota State University (SDSTATE), Dartmouth College Hanover, Space Sciences Laboratory Berkeley (SSL), University of California Berkeley (UC Berkeley), University of California (UC)-University of California (UC), Purdue University West Lafayette, Department of Geology Lund, Lund University Lund, College of Earth, Ocean and Atmospheric Sciences Corvallis (CEOAS), Oregon State University (OSU), New Mexico Institute of Mining and Technology New Mexico Tech (NMT), Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), 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 Grenoble Alpes 2016-2019 (UGA 2016-2019 )-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)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ), Lamont-Doherty Earth Observatory (LDEO), Columbia University New York, Earth and Environmental Systems Institute (EESI), Pennsylvania State University (Penn State), Penn State System-Penn State System
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: [SDE]Environmental Sciences; Antarctic; West Antarctic Ice Sheet; Hulu; Antarc*; ice core; Ice Sheet
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-01387723; https://hal-insu.archives-ouvertes.fr/insu-01387723/document; https://hal-insu.archives-ouvertes.fr/insu-01387723/file/CLIMATE%20OF%20THE%20PAST%20-%20%20The%20WAIS%20Divide%20deep%20ice%20core%20WD2014%20chronology%20-%20Part%202%20Annual-layer%20counting%200-31%20ka%20BP.pdf; https://doi.org/10.5194/cp-12-769-2016-supplement

International audience We present the WD2014 chronology for the upper part (0–2850 m; 31.2 ka BP) of the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core. The chronology is based on counting of annual layers observed in the chemical, dust and electrical conductivity records. These layers are caused by seasonal changes in the source, transport, and deposi-tion of aerosols. The measurements were interpreted manually and with the aid of two automated methods. We validated the chronology by comparing to two high-accuracy, absolutely dated chronologies. For the Holocene, the cos-mogenic isotope records of 10 Be from WAIS Divide and 14 C for IntCal13 demonstrated that WD2014 was consistently accurate to better than 0.5 % of the age. For the glacial period, comparisons to the Hulu Cave chronology demonstrated that WD2014 had an accuracy of better than 1 % of the age at three abrupt climate change events between 27 and 31 ka. WD2014 has consistently younger ages than Green-land ice core chronologies during most of the Holocene. For Published by Copernicus Publications on behalf of the European Geosciences Union. 770 M. Sigl et al.: The WAIS Divide deep ice core WD2014 chronology the Younger Dryas–Preboreal transition (11.595 ka; 24 years younger) and the Bølling–Allerød Warming (14.621 ka; 7 years younger), WD2014 ages are within the combined uncertainties of the timescales. Given its high accuracy, WD2014 can become a reference chronology for the Southern Hemisphere, with synchronization to other chronologies feasible using high-quality proxies of volcanism, solar activity , atmospheric mineral dust, and atmospheric methane concentrations.