Town, Michael S; Steen-Larsen, Hans Christian; Wahl, Sonja; Faber, Anne-Katrine (2023): Water isotopologues of near-surface polar snow from short (1-m) snow cores, extracted from the EastGRIP site on Greenland Ice Sheet during summers 2017-2019 with age-depth model [dataset publication series]. PANGAEA, https://doi.org/10.1594/PANGAEA.958540

Four data sets of water isotopologues and their products based on a time-resolved array of 1-m snow profiles extracted from the EastGRIP site on the Greenland Ice Sheet. This data product is derived from two data sets from the same EastGRIP site (Behrens et al, 2023; Steen-Larsen et al., 2023). Snow profiles were extracted during the summer field seasons of 2017, 2018, and 2019. They were extracted along a wind-aligned transect approximately 300 m long. All snow profiles were taken 1-cm resolution from 0-10 cm, and 2-cm resolution from 10-100 cm. The 1-sigma uncertainty of the d18O data is 0.11 ‰. The 1-sigma uncertainty of the dD data is 0.8 ‰. Most snow profiles are not the full 100 cm depth due to compression and loss during extraction. Each extraction date represents a time when snow cores were taken at up to six different tracks spaced 50 m apart along a line perpendicular to the prevailing (westward) wind direction. Taken together, these profiles represent a large area of the ice sheet, mitigating stratigraphic and other noise in the isotopic content. Starting from the initial extraction date on 5 May 2017, each subsequent snow profile extraction along a given track was performed approximately 1-m upwind of the previous extraction. Changes in snow height were measured between each extraction and incorporated into each profile. Changes in snow height between years is not accounted for in this data set. A depth-age model was developed for each profile by matching maximum and minimum d18O values to maximum and minimum month mean 2-m air temperature from nearby PROMICE weather data (Fausto et al., 2021), respectively. Two different depth-age models were applied to the deepest parts of each profile without clear maxima or minima tie points. The first model adopts a mean accumulation rate (MAcR) for the approximate time range representing the snow in question. The accumulation rate used here is derived from changes in surface height derived from the Fausto et al. (2021) data set. The second depth-age model adjusts the MAcR results in time based on matching d18O-values with expected transitional d18O values. The two final products are both interpolated to a regular depth grid of 1-cm resolution and a regular time grid of 1-day resolution. Deuterium excess is calculated as both

1) d = dD - 8*d18O; (Merlivat and Jouzel, 1979)

and

2) dln = ln(dD + 1) - 8.47(ln(d18O+1)) - 28.5(ln(d18O+1))2; (Uemura et al., 2012).