A Greenland-wide Holocene deglaciation model and building an accompanying ¹⁴C database

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.