Assessing ice margin fluctuations on differing timescales

The observational record of ice margin position reveals asynchrony in both the timing and magnitude of Greenland Ice Sheet (GrIS) margin fluctuations and illustrates the complex reactions of ice sheets to climatic perturbations. In this study, we reconstruct the timing and pattern of middle- and late-Holocene GrIS margin fluctuations at two locations, ~190 km apart, in central West Greenland using radiocarbon-dated sediment cores from proglacial-threshold lakes. Our results demonstrate that deglaciation occurs at both sites during the early Holocene, with the ice sheet remaining in a smaller-than-present ice margin configuration until ~500 years ago when it readvanced into lake catchments at both sites. At our northern site, Sermeq Kujatdleq, the late-Holocene advance of the GrIS approached maximum position during the past 280 years, with the culmination of the advance occurring at AD 1992–1994, and modern retreat was underway by AD 1998–2001. In contrast, field and observational evidence suggest that the GrIS at our southern site, Nordenskiöld Gletscher, has been advancing or stable throughout the 20th century. These results, in conjunction with previous work in the region, highlight the asynchronous nature of late-Holocene advances and subsequent modern retreat, implying that local variability, such as ice velocity or ice dynamics, is responsible for modulating ice margin response to changes in climate on these decadal to centennial timescales. Additional high-resolution records of past ice sheet fluctuations are needed to inform and more accurately constrain our predictions of future cryosphere response to changes in climate

Climate change · Climatology · Cryosphere · Deglaciation · Geography · Greenland ice sheet · Groenlandia · Holocene · Ice core · Ice sheet · Physical geography · Sea ice · Climate change and permafrost · Cryospheric studies and observations · Geology and Paleoclimatology Research · Geology · Oceanography

• Glacier and ocean variability in Ata Sund, west Greenland, since 1400 CE

  Open Access•Fanny Ekblom Johansson, David Johannes Wangner et al.•The Holocene•2020

  Añadir item

• Dynamics of the last ice sheet on the northern fringe of Poland

  Open Access•Karol Tylmann, Vincent Rinterknecht et al.•Quaternary International•2026

  Añadir item

• Holocene Environmental Variability in Southern Greenland Inferred from Lake Sediments

  Open Access•Michael R Kaplan, Alexander P Wolfe et al.•Quaternary Research•2002

  Añadir item

• Recent Warming Reverses Long-Term Arctic Cooling

  Open Access•Darrell S Kaufman, David P Schneider et al.•Science•2009

  Añadir item

• Atmospheric Radiocarbon for the Period 1950–2010

  Open Access•Quan Hua, Mike Barbetti et al.•Radiocarbon•2013

  Añadir item