Deglaciation of northwestern Greenland during Marine Isotope Stage 11

Andrew J Christ; Tammy M Rittenour; Paul R Bierman; Benjamin A Keisling; Paul C Knutz; Tonny B Thomsen; Nynke Keulen; Julie C Fosdick; Sidney R Hemming; Jean-Louis Tison; Pierre-Henri Blard; Jørgen P Steffensen; Marc W Caffee; Lee B Corbett; Dorthe Dahl-Jensen; David P Dethier; Alan J Hidy; Nicolas Perdrial; Dorothy M Peteet; Eric J Steig; Elizabeth K Thomas

doi:10.1126/science.ade4248

Deglaciation of northwestern Greenland during Marine Isotope Stage 11

Science. 2023 Jul 21;381(6655):330-335. doi: 10.1126/science.ade4248. Epub 2023 Jul 20.

Authors

Andrew J Christ^{1

2}, Tammy M Rittenour³, Paul R Bierman^{1

2}, Benjamin A Keisling⁴, Paul C Knutz⁵, Tonny B Thomsen⁵, Nynke Keulen⁵, Julie C Fosdick⁶, Sidney R Hemming⁷, Jean-Louis Tison⁸, Pierre-Henri Blard^{8

9}, Jørgen P Steffensen¹⁰, Marc W Caffee^{11

12}, Lee B Corbett², Dorthe Dahl-Jensen^{10

13}, David P Dethier¹⁴, Alan J Hidy¹⁵, Nicolas Perdrial^{1

16}, Dorothy M Peteet^{7

17}, Eric J Steig¹⁸, Elizabeth K Thomas¹⁹

Affiliations

¹ Rubenstein School of the Environment and Natural Resources, University of Vermont, Burlington, VT 05405, USA.
² Gund Institute for Environment, University of Vermont, Burlington, VT 05405, USA.
³ Department of Geosciences, Utah State University, Logan, UT 84322, USA.
⁴ University of Texas Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78754, USA.
⁵ Geological Survey of Denmark and Greenland, 1350 Copenhagen, Denmark.
⁶ Department of Earth Sciences, University of Connecticut, Storrs, CT 06269, USA.
⁷ Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, USA.
⁸ Laboratoire de Glaciologie, DGES-IGEOS, Université Libre de Bruxelles, 1050 Brussels, Belgium.
⁹ Centre de Recherches Pétrographiques et Géochimiques, CNRS, Université de Lorraine, 54500 Nancy, France.
¹⁰ Centre for Ice and Climate, PICE, Niels Bohr Institute, University of Copenhagen, 2200 Copenhagen, Denmark.
¹¹ Department of Physics and Astronomy, Purdue University, West Lafayette, IN 47907, USA.
¹² Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN 47907, USA.
¹³ Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
¹⁴ Department of Geosciences, Williams College, Williamstown, MA 01267, USA.
¹⁵ Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
¹⁶ Department of Geography and Geosciences, University of Vermont, Burlington, VT 05405, USA.
¹⁷ NASA Goddard Institute for Space Studies, New York, NY 10025, USA.
¹⁸ Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195, USA.
¹⁹ Department of Geology, University at Buffalo, Buffalo, NY 14260, USA.

PMID: 37471537
DOI: 10.1126/science.ade4248

Abstract

Past interglacial climates with smaller ice sheets offer analogs for ice sheet response to future warming and contributions to sea level rise; however, well-dated geologic records from formerly ice-free areas are rare. Here we report that subglacial sediment from the Camp Century ice core preserves direct evidence that northwestern Greenland was ice free during the Marine Isotope Stage (MIS) 11 interglacial. Luminescence dating shows that sediment just beneath the ice sheet was deposited by flowing water in an ice-free environment 416 ± 38 thousand years ago. Provenance analyses and cosmogenic nuclide data and calculations suggest the sediment was reworked from local materials and exposed at the surface <16 thousand years before deposition. Ice sheet modeling indicates that ice-free conditions at Camp Century require at least 1.4 meters of sea level equivalent contribution from the Greenland Ice Sheet.