High resolution isotopic measurements from 4 Greenland Ice Sheet (GrIS) ice cores (2021-2024)

Lead pollution found in ice cores extracted from polar ice sheets and glaciers reflects human activities, including mining and smelting related to early silver production, as well as coal, oil, and gasoline burning. Isotopic analyses of lead in glacier ice can be used to identify past changes in emission sources. Between October 2021 and September 2024, lead isotopic records were developed from four Greenland Ice Cores (GrIP) (Tunu2022a, Tunu2022b, North Greenland Ice Core Project 2 [NGRIP2], and REnland ice CAP project [RECAP]) at the Desert Research Institute's Trace Chemistry/Ice Core Laboratory. Lead isotopic analyses were performed on discrete meltwater samples using a High Resolution Inductively Coupled Plasma Mass Spectrometer (HR-ICP-MS). The original overarching goals of the project, were to (1) exploit recently refined methods developed for urban geochemistry to develop high-resolution records of lead (Pb) isotopes (206Pb, 207Pb, 208Pb) in Greenland ice cores, (2) use these records to identify and quantify changes in anthropogenic emission sources during the past 2,500 years, and (3) evaluate linkages between these changes and historical events extending from Antiquity through the Middle Ages to the present. These records have implications for understanding of how events such as plague, social upheaval, warfare, and technological advancements in mining and smelting influenced human history.