Deglaciation of northwestern Greenland during Marine Isotope Stage 11

• 成果类型: Article
• 署名作者: Christ, Andrew J.; Rittenour, Tammy M.; Bierman, Paul R.; Keisling, Benjamin A.; Knutz, Paul C.; Thomsen, Tonny B.; Keulen, Nynke; Fosdick, Julie C.; Hemming, Sidney R.; Tison, Jean-Louis; Blard, Pierre-Henri; Steffensen, Jrgen P.; Caffee, Marc W.; Corbett, Lee B.; Dahl-Jensen, Dorthe; Dethier, David P.; Hidy, Alan J.; Perdrial, Nicolas; Peteet, Dorothy M.; Steig, Eric J.; Thomas, Elizabeth K.
• 署名单位: University of Vermont; University of Vermont; Utah System of Higher Education; Utah State University; University of Texas System; University of Texas Austin; Geological Survey Of Denmark & Greenland; University of Connecticut; Columbia University; Universite Libre de Bruxelles; Centre National de la Recherche Scientifique (CNRS); Universite de Lorraine; University of Copenhagen; Niels Bohr Institute; Purdue University System; Purdue University; Purdue University System; Purdue University; University of Manitoba; Williams College; United States Department of Energy (DOE); Lawrence Livermore National Laboratory; University of Vermont; National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center; Goddard Institute for Space Studies; University of Washington; University of Washington Seattle; State University of New York (SUNY) System; University at Buffalo, SUNY
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-13302
• DOI: 10.1126/science.ade4248
• 发表日期: 2023-07-21
• 页码: 330-335
• 关键词: natural reference material; ice-sheet; u-pb; southern greenland; climate; geochronology; luminescence; STANDARDS; EVOLUTION; feldspar

摘要

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.