The paper Glacial episodes of a freshwater Arctic Ocean covered by a thick ice shelf [1]: > Here we provide evidence for at least two episodes during which the

The paper Glacial episodes of a freshwater Arctic Ocean covered by a thick ice shelf [1]: > Here we provide evidence for at least two episodes during which the Arctic Ocean and the adjacent Nordic seas were not only covered by an extensive ice shelf, but also filled entirely with fresh water, causing a widespread absence of thorium-230 in marine sediments. We propose that these Arctic freshwater intervals occurred 70,000–62,000 years before present and approximately 150,000–131,000 years before present, corresponding to portions of marine isotope stages 4 and 6. > A freshwater mass of this size—stored in oceans, rather than land—suggests that a revision of sea-level reconstructions based on freshwater-sensitive stable oxygen isotopes may be required, and that large masses of fresh water could be delivered to the north Atlantic Ocean on very short timescales. [1] https://www.nature.com/articles/s41586-021-03186-y https://www.nature.com/articles/s41586-021-03186-y