High-resolution isotopic evidence for a potential Saharan provenance of Greenland glacial dust ...

• Main Authors: Han, Changhee, Do Hur, Soon, Han, Yeongcheol, Lee, Khanghyun, Hong, Sungmin, Erhardt, Tobias, Fischer, Hubertus, Svensson, Anders M., Steffensen, Jørgen Peder, Vallelonga, Paul
• Format: Text
• Language: English
• Published: Nature Publishing Group 2018
• Subjects: 530 Physics; Greenland; ice core
• Online Access: https://dx.doi.org/10.7892/boris.128731; https://boris.unibe.ch/128731/

Dust concentrations in Greenland ice show pronounced glacial/interglacial variations with almost two orders of magnitude increase during the Last Glacial Maximum. Greenland glacial dust was previously sourced to two East Asian deserts: the Taklimakan and Gobi deserts. Here we report the first high-resolution Pb and Sr isotopic evidence for a significant Saharan dust influence in Greenland during the last glacial period, back to ~31 kyr ago, from the Greenland NEEM ice core. We find that during Greenland Stadials 3–5.1 (~31 to 23 kyr ago), the primary dust provenance was East Asia, as previously proposed. Subsequently, the Saharan isotopic signals emerge during Greenland Stadials 2.1a–2.1c (~22.6 to 14.7 kyr ago) and from the late Bølling-Allerød to the Younger Dryas periods (~13.6 to 12 kyr ago), coincident with increased aridity in the Sahara and efficient northward transport of dust during these cold periods. A mixing isotopic model proposes the Sahara as an important source, accounting for contribution to ...