Millennial-scale variability in Greenland dust provenance during Dansgaard-Oeschger events of the last glacial period.

East Asian deserts remained the dominant source of Greenland dust throughout the last glacial period, while Sahara contributions increased during stadials, based on ~800 y Pb/Sr and mineralogical records.

• Why it matters: Greenland dust concentration rises during cold stadials, but the millennial-scale shifts in source-region contributions during Dansgaard-Oeschger events are still poorly constrained.
• What they did: Using high-resolution (~800 y) Pb and Sr isotopic, mineralogical, and geochemical data from North Greenland Eemian Ice Drilling ice-core samples spanning the entire LGP, they compared stadial versus interstadial signatures and matched them to proposed source areas.
• The result: Pb and Sr isotopes, kaolinite-to-chlorite ratios, and chemical index of alteration values were higher in stadials than interstadials, implying circulation changes that modulated dust transport and increased Sahara input during stadials.

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