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Ocean heat drives rapid basal melt of the Totten Ice Shelf.

ABSTRACT: Mass loss from the West Antarctic ice shelves and glaciers has been linked to basal melt by ocean heat flux. The Totten Ice Shelf in East Antarctica, which buttresses a marine-based ice sheet with a volume equivalent to at least 3.5 m of global sea-level rise, also experiences rapid basal melt, but the role of ocean forcing was not known because of a lack of observations near the ice shelf. Observations from the Totten calving front confirm that (0.22 ± 0.07) × 106 m3 s-1 of warm water enters the cavity through a newly discovered deep channel. The ocean heat transport into the cavity is sufficient to support the large basal melt rates inferred from glaciological observations. Change in ocean heat flux is a plausible physical mechanism to explain past and projected changes in this sector of the East Antarctic Ice Sheet and its contribution to sea level.

SUBMITTER: Rintoul SR

PROVIDER: S-EPMC5161426 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Ocean heat drives rapid basal melt of the Totten Ice Shelf.

Rintoul Stephen Rich SR Silvano Alessandro A Pena-Molino Beatriz B van Wijk Esmee E Rosenberg Mark M Greenbaum Jamin Stevens JS Blankenship Donald D DD

Science advances 20161216 12

Mass loss from the West Antarctic ice shelves and glaciers has been linked to basal melt by ocean heat flux. The Totten Ice Shelf in East Antarctica, which buttresses a marine-based ice sheet with a volume equivalent to at least 3.5 m of global sea-level rise, also experiences rapid basal melt, but the role of ocean forcing was not known because of a lack of observations near the ice shelf. Observations from the Totten calving front confirm that (0.22 ± 0.07) × 10<sup>6</sup> m<sup>3</sup> s<sup ...[more]

PMID: 28028540

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