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.