Thermohaline structure and circulation beneath the Langhovde Glacier ice shelf in East Antarctica.

ABSTRACT: Basal melting of ice shelves is considered to be the principal driver of recent ice mass loss in Antarctica. Nevertheless, in-situ oceanic data covering the extensive areas of a subshelf cavity are sparse. Here we show comprehensive structures of temperature, salinity and current measured in January 2018 through four boreholes drilled at a ~3-km-long ice shelf of Langhovde Glacier in East Antarctica. The measurements were performed in 302-12 m-thick ocean cavity beneath 234-412 m-thick ice shelf. The data indicate that Modified Warm Deep Water is transported into the grounding zone beneath a stratified buoyant plume. Water at the ice-ocean interface was warmer than the in-situ freezing point by 0.65-0.95°C, leading to a mean basal melt rate estimate of 1.42 m a^-1. Our measurements indicate the existence of a density-driven water circulation in the cavity beneath the ice shelf of Langhovde Glacier, similar to that proposed for warm-ocean cavities of larger Antarctic ice shelves.

SUBMITTER: Minowa M 

PROVIDER: S-EPMC8270922 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature