Reconstructions of mean-annual Greenland temperature and precipitation for the past 20,000 years and the ice-core records used to create the reconstructions 2020

• Main Authors: Badgeley, Jessica A., Steig, Eric J., Hakim, Gregory J., Fudge, Tyler J.
• Format: Dataset
• Language: English
• Published: NSF Arctic Data Center 2020
• Subjects: air temperature reconstruction; precipitation reconstruction; Greenland; ice core records; water isotopes; accumulation rate; data assimilation; paleoclimate; Greenland ice core; Greenland Ice core Project; GRIP; ice core; NGRIP; North Greenland; North Greenland Ice Core Project
• Online Access: https://dx.doi.org/10.18739/a2599z26m; https://arcticdata.io/catalog/view/doi:10.18739/A2599Z26M

This dataset provides mean-annual surface temperature and precipitation reconstructions for Greenland over the past 20,000 years and the proxy records used to create the reconstructions. For each reconstruction, ice-core records were assimilated with a transient climate simulation using the ensemble Kalman filter. The reconstructions differ by assumptions made during preparation of the ice-core records and parameters set in the assimilation process. The temperature values are anomalies with respect to the reference period, 1850-2000 CE, while the precipitation values are fractional precipitation rates with respect to the same reference period. The ice-core data was previously published except for the accumulation rate records from Dye3, Greenland Ice Core Project (GRIP), and North Greenland Ice Core Project (NGRIP). To extract the accumulation signal from layer-thickness, the layers were destrained using assumptions about the history of ice flow. Here, a one-dimensional ice-flow model was used to calculate the cumulative vertical strain the layers have experienced at each core site. Based on a range of plausible ice-flow parameters, three scenarios were developed for each site: 'low', 'moderate', and 'high', where the names reflect the relative magnitude of accumulation in the glacial and early Holocene. More information on both the reconstructions and the ice-core records is provided in the following paper: Badgeley, J. A., Steig, E. J., Hakim, G. J. and Fudge, T. J.: Greenland temperature and precipitation over the last 20,000 years using data assimilation, Climate of the Past, in press, 2020 (preprint: https://doi.org/10.5194/cp-2019-164). Please cite this paper if you use the climate reconstructions or the accumulation records for GRIP, NGRIP, or Dye3.