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Millennial-scale glacial climate variability in Southeastern Alaska follows Dansgaard-Oeschger cyclicity.

ABSTRACT: A stalagmite from Prince of Wales Island grew episodically between ~75,000 and ~11,100?yr BP; interrupted by seven hiatuses. Hiatuses most likely correspond to permafrost development and a temperature drop of up to 5?°C from modern conditions. Intervals of calcite deposition place tight constraints on the timing of mild climatic episodes in Alaska during the last glacial period, when permafrost was absent, allowing water infiltration into the karst system. These periods of calcite deposition are synchronous, within dating uncertainties, with Greenland Interstadials 1, 10, 11, 12c, 14b-14e, 16.1a, 17.2, and 20c.

SUBMITTER: Wilcox PS

PROVIDER: S-EPMC6536552 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Millennial-scale glacial climate variability in Southeastern Alaska follows Dansgaard-Oeschger cyclicity.

Wilcox Paul S PS Dorale Jeffrey A JA Baichtal James F JF Spötl Christoph C Fowell Sarah J SJ Edwards R Lawrence RL Kovarik Johanna L JL

Scientific reports 20190527 1

A stalagmite from Prince of Wales Island grew episodically between ~75,000 and ~11,100 yr BP; interrupted by seven hiatuses. Hiatuses most likely correspond to permafrost development and a temperature drop of up to 5 °C from modern conditions. Intervals of calcite deposition place tight constraints on the timing of mild climatic episodes in Alaska during the last glacial period, when permafrost was absent, allowing water infiltration into the karst system. These periods of calcite deposition are ...[more]

PMID: 31133661

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