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{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,1,19]],"date-time":"2024-01-19T03:22:11Z","timestamp":1705634531562},"reference-count":102,"publisher":"Copernicus GmbH","issue":"3","license":[{"start":{"date-parts":[[2023,3,15]],"date-time":"2023-03-15T00:00:00Z","timestamp":1678838400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000270","name":"Natural Environment Research Council","doi-asserted-by":"publisher","award":["NE\/N011228\/1"]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["The Cryosphere"],"abstract":"<jats:p>Abstract. Nioghalvfjerdsbrae, or 79\u2218\u2009N\u00a0Glacier, is the largest marine-terminating glacier draining the Northeast Greenland Ice Stream (NEGIS). In recent\nyears, its \u223c\u200970\u2009km long fringing ice shelf (hereafter referred to as the 79\u2218\u2009N\u00a0ice shelf) has thinned, and a number of small\ncalving events highlight its sensitivity to climate warming. With the continued retreat of the 79\u2218\u2009N\u00a0ice shelf and the potential for\naccelerated discharge from NEGIS, which drains\u00a016\u2009% of the Greenland Ice Sheet (GrIS), it has become increasingly important to understand the\nlong-term history of the ice shelf in order to put the recent changes into perspective and to judge their long-term significance. Here, we\nreconstruct the Holocene dynamics of the 79\u2218\u2009N\u00a0ice shelf by combining radiocarbon dating of marine molluscs from isostatically uplifted\nglaciomarine sediments with a multi-proxy investigation of two sediment cores recovered from Bl\u00e5s\u00f8, a large epishelf lake 2\u201313\u2009km\nfrom the current grounding line of 79\u2218\u2009N\u00a0Glacier. Our reconstructions suggest that the ice shelf retreated between\u00a08.5 and\n4.4\u2009ka\u2009cal\u2009BP, which is consistent with previous work charting grounding line and ice shelf retreat to the coast as well as open marine\nconditions in Nioghalvfjerdsbrae. Ice shelf retreat followed a period of enhanced atmospheric and ocean warming in the Early Holocene. Based on our\ndetailed sedimentological, microfaunal, and biomarker evidence, the ice shelf reformed at Bl\u00e5s\u00f8 after 4.4\u2009ka\u2009cal\u2009BP, reaching a\nthickness similar to present by 4.0\u2009ka\u2009cal\u2009BP. Reformation of the ice shelf coincides with decreasing atmospheric temperatures, the increased\ndominance of Polar Water, a reduction in Atlantic Water, and (near-)perennial sea-ice cover on the adjacent continental shelf. Along with\navailable climate archives, our data indicate that the 79\u2218\u2009N\u00a0ice shelf is susceptible to collapse at mean atmospheric and ocean temperatures \u223c\u20092\u2009\u2218C warmer than present, which could be achieved by the middle of this century under some emission scenarios. Finally,\nthe presence of \u201cmarine\u201d markers in the uppermost part of the Bl\u00e5s\u00f8 sediment cores could record modern ice shelf thinning, although the\nsignificance and precise timing of these changes requires further work.\n <\/jats:p>","DOI":"10.5194\/tc-17-1247-2023","type":"journal-article","created":{"date-parts":[[2023,3,15]],"date-time":"2023-03-15T09:41:23Z","timestamp":1678873283000},"page":"1247-1270","source":"Crossref","is-referenced-by-count":3,"title":["Holocene history of the 79\u00b0\u2009N ice shelf reconstructed from epishelf lake and uplifted glaciomarine sediments"],"prefix":"10.5194","volume":"17","author":[{"ORCID":"http:\/\/orcid.org\/0000-0002-1333-2544","authenticated-orcid":false,"given":"James A.","family":"Smith","sequence":"first","affiliation":[]},{"given":"Louise","family":"Callard","sequence":"additional","affiliation":[]},{"ORCID":"http:\/\/orcid.org\/0000-0002-2048-0019","authenticated-orcid":false,"given":"Michael J.","family":"Bentley","sequence":"additional","affiliation":[]},{"given":"Stewart S. R.","family":"Jamieson","sequence":
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