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Deglacial mobilization of pre-aged terrestrial carbon from degrading permafrost.

ABSTRACT: The mobilization of glacial permafrost carbon during the last glacial-interglacial transition has been suggested by indirect evidence to be an additional and significant source of greenhouse gases to the atmosphere, especially at times of rapid sea-level rise. Here we present the first direct evidence for the release of ancient carbon from degrading permafrost in East Asia during the last 17?kyrs, using biomarkers and radiocarbon dating of terrigenous material found in two sediment cores from the Okhotsk Sea. Upscaling our results to the whole Arctic shelf area, we show by carbon cycle simulations that deglacial permafrost-carbon release through sea-level rise likely contributed significantly to the changes in atmospheric CO2 around 14.6 and 11.5?kyrs BP.

SUBMITTER: Winterfeld M

PROVIDER: S-EPMC6131488 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Deglacial mobilization of pre-aged terrestrial carbon from degrading permafrost.

Winterfeld Maria M Mollenhauer Gesine G Dummann Wolf W Köhler Peter P Lembke-Jene Lester L Meyer Vera D VD Hefter Jens J McIntyre Cameron C Wacker Lukas L Kokfelt Ulla U Tiedemann Ralf R

Nature communications 20180910 1

The mobilization of glacial permafrost carbon during the last glacial-interglacial transition has been suggested by indirect evidence to be an additional and significant source of greenhouse gases to the atmosphere, especially at times of rapid sea-level rise. Here we present the first direct evidence for the release of ancient carbon from degrading permafrost in East Asia during the last 17 kyrs, using biomarkers and radiocarbon dating of terrigenous material found in two sediment cores from th ...[more]

PMID: 30201999

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