Ice Core δ 18 O Record Linked to Western Arctic Sea Ice Variability

A strong correlation between ice core δ¹⁸O records and western Arctic sea ice variability has been identified, revealing that enriched δ¹⁸O values in the Bona-Churchill (B-C) ice core from southeast Alaska correspond to reduced sea ice cover in the region. This relationship is linked to increased southerly flow and warmer waters in the Bering Sea, which modulate heat flux through the Bering Strait and influence Arctic sea ice dynamics. The study utilized isotope-enabled model data, reanalysis data, and observations to explore these mechanisms, finding a significant negative correlation (r = −0.80, p < .001) between the B-C δ¹⁸O record and western Arctic sea ice duration reconstructed from Chukchi Sea sediment cores. This pattern suggests that during periods like the Little Ice Age, prolonged warm Arctic/cold continent conditions and a northwestward shift in the North Pacific storm track may have contributed to reduced sea ice cover.

Porter, S. E., Mosley‐Thompson, E., & Thompson, L. G. (2019). Ice Core δ ¹⁸ O Record Linked to Western Arctic Sea Ice Variability. Journal of Geophysical Research: Atmospheres, 124(20), 10784–10801. Portico. https://doi.org/10.1029/2019jd031023