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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.
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Chemical, elemental, and isotopic measurements of the Tunu2022a and Tunu2022b ice core collected from northeastern Greenland; 2022-2024.
The original goal of the proposed research was to develop accurately dated, high-resolution, ice-core records of a broad range of elements and chemical species to expand and extend recently identified, causal linkages between (1) ancient societies; (2) volcanism and hydroclimate; and (3) wars, plagues, social unrest, and economic activity--while engaging ancient and pre-modern historians, economists, and students in consilient ice core research and interpretation. Underpinning these efforts was the proposed collection and analysis of a ~440 meter (m) ice core (Tunu2020 but delayed by COVID until 2022) from the northeastern flank of the Greenland ice sheet that was to be used to develop accurately dated, sub-annually resolved, multi-parameter records during the past 4k years of volcanism, heavy-metal pollution from ancient mining and smelting activities, as well as other indicators of climate and human activities. Because core quality and the drill penetration rate decreased very dramatically below ~165 m, however, two cores were collected instead of a single longer core. The Tunu2022a and Tunu2022b cores were located 50 m apart and about 5 kilometer (km) from the Tunu2013 core site.
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- Award ID(s):
- 1925417
- PAR ID:
- 10566775
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- EARTH SCIENCE > PALEOCLIMATE > ICE CORE RECORDS EARTH SCIENCE > ATMOSPHERE > AIR QUALITY > LEAD EARTH SCIENCE > ATMOSPHERE > AEROSOLS > PARTICULATE MATTER
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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