EGU25-11339, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-11339
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
A Greenland-wide Holocene deglaciation model and building an accompanying 14C database
Astrid Rosenberg1, Gregor Luetzenburg2, Ole Bennike2, Kristian Kjellerup Kjeldsen2, and Nicolaj Krog Larsen1
Astrid Rosenberg et al.
  • 1University of Copenhagen, Globe institute, Section for GeoGenetics, Denmark (astrid.rosenberg@sund.ku.dk)
  • 2Geological Survey of Denmark and Greenland (GEUS), Copenhagen, Denmark

The timing of the Greenland Ice Sheet's retreat from its extent during the Last Glacial Maximum is a key element in constraining the sensitivity of the ice sheet to climate forcing. Although different deglaciation models have been published in previous years (Bennike, 2002; Funder et al., 2011; Sinclair et al., 2016; Leger et al., 2024), these models are limited by the number of samples used or their geographical extent. Therefore, the models have not been able to adequately resolve the deglaciation chronology of the Greenland Ice Sheet.

In this project, we aim to develop a Greenland-wide deglaciation model based on a new compilation of 14C dates, cosmogenic nuclide dates, OSL dates, and geomorphological evidence. The new compilation of 14C samples will be provided as an open-access database: GreenDated.

Within GreenDated, we aim to include all published 14C data from Greenland and the surrounding ocean shelf. All sample entries will as a minimum include information on location, and a categorization of the depositional environment and the sampled material. These steps will ensure accessibility for future users and enable easy extraction of data from the database. We will also recalibrate all the 14C data using the newest calibration curves (Heaton et al., 2020; Reimer et al., 2020) and adjust for differences in old normalization techniques, enabling easy recalibration of data for future users. Lastly, we will conduct a quality assessment based on the protocol used in the Dated (Hughes et al., 2016) and SvalHola (Farnsworth et al., 2020) databases, with the addition of an automated scoring system, seeking to limit bias from the authors.

Ultimately, the deglaciation model and the accompanying GreenDated database will provide a complete and thorough constraint on the Greenland Ice Sheet’s retreat from the Last Glacial Maximum position.

References:
Bennike, O. (2002) ‘Late Quaternary history of Washington Land, North Greenland’, Boreas, 31(3), pp. 260–272. https://doi.org/10.1111/j.1502-3885.2002.tb01072.x.
Farnsworth, W.R. et al. (2020) ‘Holocene glacial history of Svalbard: Status, perspectives and challenges’, Earth-Science Reviews, 208, p. 103249. https://doi.org/10.1016/j.earscirev.2020.103249.
Funder, S. et al. (2011) ‘The Greenland Ice Sheet During the Past 300,000 Years: A Review’, Developments in Quaternary Science, 15, pp. 699–713. https://doi.org/10.1016/B978-0-444-53447-7.00050-7.
Heaton, T.J. et al. (2020) ‘Marine20—The Marine Radiocarbon Age Calibration Curve (0–55,000 cal BP)’, Radiocarbon, 62(4), pp. 779–820. https://doi.org/10.1017/rdc.2020.68.
Hughes, A.L.C. et al. (2016) ‘The last Eurasian ice sheets – a chronological database and time-slice reconstruction, DATED-1’, Boreas, 45(1), pp. 1–45.  https://doi.org/10.1111/bor.12142.
Leger, T.P.M. et al. (2024) ‘A Greenland-wide empirical reconstruction of paleo ice sheet retreat informed by ice extent markers: PaleoGrIS version 1.0’, Climate of the Past, 20(3), pp. 701–755. https://doi.org/10.5194/cp-20-701-2024.
Reimer, P.J. et al. (2020) ‘The IntCal20 Northern Hemisphere Radiocarbon Age Calibration Curve (0–55 cal kBP)’, Radiocarbon, 62(4), pp. 725–757. https://doi.org/10.1017/rdc.2020.41.
 inclair, G. et al. (2016) ‘Diachronous retreat of the Greenland ice sheet during the last deglaciation’, Quaternary Science Reviews, 145, pp. 243–258. https://doi.org/10.1016/j.quascirev.2016.05.040.

How to cite: Rosenberg, A., Luetzenburg, G., Bennike, O., Kjellerup Kjeldsen, K., and Krog Larsen, N.: A Greenland-wide Holocene deglaciation model and building an accompanying 14C database, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11339, https://doi.org/10.5194/egusphere-egu25-11339, 2025.