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TitleHolocene thinning of the Greenland ice sheet
AuthorVinther, B M; Buchart, S L; Clausen, H B; Dahl-Jensen, D; Johnsen, S J; Fisher, D A; Koerner, R M; Raynaud, D; Lipenkov, V; Andersen, K K; Blunier, T; Rasmussen, S O; Steffensen, J P; Svensson, A M
SourceNature (London) vol. 461, 2009 p. 385-388,
Alt SeriesEarth Sciences Sector, Contribution Series 20090324
Mediapaper; on-line; digital
File formathtml; pdf
AreaEllesmere Island; Greenland; Canada
Lat/Long WENS-72.0000 -20.0000 84.0000 58.0000
Subjectssurficial geology/geomorphology; environmental analysis; environmental studies; environmental impacts; climate, arctic; climate effects; climate; Holocene; ice samples; ice thickness; icefields; ice; ice conditions; cores; core studies; Greenland Ice Sheet; climate change; Cenozoic; Quaternary
ProgramPaleoenvironmental Perspectives on Climate Change, Climate Change Geoscience
LinksSupplementary information / Information supplementaire
AbstractOn entering an era of global warming, the stability of the Greenland ice sheet (GIS) is an important concern1, especially in the light of new evidence of rapidly changing flow and melt conditions at the GIS margins2. Studying the response of the GIS to past climatic change may help to advance our understanding of GIS dynamics. Existing evidence from stable isotopes (d18O) in water from GIS ice cores suggests that Holocene climate variability on the GIS differed spatially3 and that a consistent Holocene climate optimum-the unusually warm period from about 9,000 to 6,000 years ago found in many northern-latitude palaeoclimate records4-did not exist. Here we extract both the Greenland Holocene temperature history and the evolution of GIS surface elevation at four GIS locations. We achieve this by comparing d18O from GIS ice cores3,5 with d18O from ice cores from small marginal icecaps. Contrary to the earlier and inconsistent d18O evidence from ice cores3,6, our new temperature history reveals a pronounced Holocene climatic optimum in Greenland coinciding with maximum thinning near the GIS margins. Our d18O-based results are corroborated by the air content of ice cores, a proxy for surface elevation7. State-of-the-art ice sheet models are generally found to be underestimating the extent and changes in GIS elevation and area; our findings may help to improve the ability of models to reproduce the GIS response to Holocene climate.