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Antarctic last interglacial isotope peak in response to sea ice retreat not ice-sheet collapse.

ABSTRACT: Several studies have suggested that sea-level rise during the last interglacial implies retreat of the West Antarctic Ice Sheet (WAIS). The prevalent hypothesis is that the retreat coincided with the peak Antarctic temperature and stable water isotope values from 128,000 years ago (128?ka); very early in the last interglacial. Here, by analysing climate model simulations of last interglacial WAIS loss featuring water isotopes, we show instead that the isotopic response to WAIS loss is in opposition to the isotopic evidence at 128?ka. Instead, a reduction in winter sea ice area of 65±7% fully explains the 128?ka ice core evidence. Our finding of a marked retreat of the sea ice at 128?ka demonstrates the sensitivity of Antarctic sea ice extent to climate warming.

SUBMITTER: Holloway MD

PROVIDER: S-EPMC4990695 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Antarctic last interglacial isotope peak in response to sea ice retreat not ice-sheet collapse.

Holloway Max D MD Sime Louise C LC Singarayer Joy S JS Tindall Julia C JC Bunch Pete P Valdes Paul J PJ

Nature communications 20160816

Several studies have suggested that sea-level rise during the last interglacial implies retreat of the West Antarctic Ice Sheet (WAIS). The prevalent hypothesis is that the retreat coincided with the peak Antarctic temperature and stable water isotope values from 128,000 years ago (128 ka); very early in the last interglacial. Here, by analysing climate model simulations of last interglacial WAIS loss featuring water isotopes, we show instead that the isotopic response to WAIS loss is in opposit ...[more]

PMID: 27526639

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