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Widespread distribution of supraglacial lakes around the margin of the East Antarctic Ice Sheet.

ABSTRACT: Supraglacial lakes are important to ice sheet mass balance because their development and drainage has been linked to changes in ice flow velocity and ice shelf disintegration. However, little is known about their distribution on the world's largest ice sheet in East Antarctica. Here, we use ~5 million km2 of high-resolution satellite imagery to identify >65,000 lakes (>1,300 km2) that formed around the peak of the melt season in January 2017. Lakes occur in most marginal areas where they typically develop at low elevations (<100?m) and on low surface slopes (<1°), but they can exist 500?km inland and at elevations >1500?m. We find that lakes often cluster a few kilometres down-ice from grounding lines and ~60% (>80% by area) develop on ice shelves, including some potentially vulnerable to collapse driven by lake-induced hydro-fracturing. This suggests that parts of the ice sheet may be highly sensitive to climate warming.

SUBMITTER: Stokes CR

PROVIDER: S-EPMC6761196 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Widespread distribution of supraglacial lakes around the margin of the East Antarctic Ice Sheet.

Stokes Chris R CR Sanderson Jack E JE Miles Bertie W J BWJ Jamieson Stewart S R SSR Leeson Amber A AA

Scientific reports 20190925 1

Supraglacial lakes are important to ice sheet mass balance because their development and drainage has been linked to changes in ice flow velocity and ice shelf disintegration. However, little is known about their distribution on the world's largest ice sheet in East Antarctica. Here, we use ~5 million km<sup>2</sup> of high-resolution satellite imagery to identify >65,000 lakes (>1,300 km<sup>2</sup>) that formed around the peak of the melt season in January 2017. Lakes occur in most marginal ar ...[more]

PMID: 31554854

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