Iceberg-rafted sediment concentrations from Greenland's outlet glaciers (2018-2022)

Samples of sediment entrained as ice-rafted debris in icebergs sourced from the Greenland ice sheet. The samples were collected to help characterize the magnitude and variability of sediment concentrations in debris-rich basal ice layers from Greenland's outlet glaciers. Samples were collected over the course of three field campaigns from 2018-2022, across three different major fjord systems in southwest (Nuup Kangerlua), central-west (Ikerasak), and east (Kangertittivaq, i.e. Scoresbysund) Greenland. Sample sites were selected from toppled icebergs that had exposed debris-rich basal ice to the surface. Samples were taken by hand, after first scraping off exposed, partially-melted ice, to ensure that entrained sediment concentrations were representative of the interior of the iceberg, and then weighed in the field. In the laboratory, samples were melted, then dried completely in a freeze-dryer before measuring the dry sediment mass. Rafted sediment concentration was calculated as the ratio of sediment mass to total sample mass.