Dataset Information

Subglacial discharge controls seasonal variations in the thermal structure of a glacial lake in Patagonia.

ABSTRACT: Water temperature in glacial lakes affects underwater melting and calving of glaciers terminating in lakes. Despite its importance, seasonal lake temperature variations are poorly understood because taking long-term measurements near the front of calving glaciers is challenging. To investigate the thermal structure and its seasonal variations, we performed year-around temperature and current measurement at depths of 58-392 m in Lago Grey, a 410-m-deep glacial lake in Patagonia. The measurement revealed critical impacts of subglacial discharge on the lake thermal condition. Water below a depth of ~100 m showed the coldest temperature in mid-summer, under the influence of glacial discharge, whereas temperature in the upper layer followed a seasonal variation of air temperature. The boundary of the lower and upper layers was controlled by the depth of a sill which blocks outflow of dense and cold glacial meltwater. Our data implies that subglacial discharge and bathymetry dictate mass loss and the retreat of lake-terminating glaciers. The cold lakewater hinders underwater melting and facilitates formation of a floating terminus.

SUBMITTER: Sugiyama S

PROVIDER: S-EPMC8563722 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Subglacial discharge controls seasonal variations in the thermal structure of a glacial lake in Patagonia.

Sugiyama Shin S Minowa Masahiro M Fukamachi Yasushi Y Hata Shuntaro S Yamamoto Yoshihiro Y Sauter Tobias T Schneider Christoph C Schaefer Marius M

Nature communications 20211102 1

Water temperature in glacial lakes affects underwater melting and calving of glaciers terminating in lakes. Despite its importance, seasonal lake temperature variations are poorly understood because taking long-term measurements near the front of calving glaciers is challenging. To investigate the thermal structure and its seasonal variations, we performed year-around temperature and current measurement at depths of 58-392 m in Lago Grey, a 410-m-deep glacial lake in Patagonia. The measurement r ...[more]

PMID: 34728649

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Dataset Information

Subglacial discharge controls seasonal variations in the thermal structure of a glacial lake in Patagonia.

Publications

Subglacial discharge controls seasonal variations in the thermal structure of a glacial lake in Patagonia.

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