Nature: World's largest ice sheet threatened by warm water tide

Westerly winds are blowing warm water toward the East Antarctic ice sheet and thinning the region's ice at an alarming rate in recent decades, a study has found

The study, published Aug.

Ice shelves float on the ocean, extending from and supporting continental glaciers, which aggregate to form ice sheets

But over the past decade, data and observations have shown that the East Antarctic ice sheet is also increasingly under threat from warm brine that is melting the ice shelves from below

90 years of data

Oceanographers Laura Herraiz-Borreguero of Australia's National Scientific Research Organisation (CSIRO) and Alberto Naveira Garabato of the University of Southampton, UK, sought to quantify the results by collating and analysing 90 years of frontal records of ocean temperature and salinity from the East Antarctic continental slope and open ocean.

They found that ocean temperatures in East Antarctica have risen by as much as 2°C since the early 20th century, and that trend is accelerating

Previous studies have recorded snapshots of warming in specific locations, such as near the Totten Glacier and the Emory Ice Shelf, only hinting at the underlying processes driving East Antarctica's ice melt

mechanism of warming

Research by Herraiz-Borreguero and Naveira Garabato shows that the southern edge of the ACC is indeed moving southward, shifting warmer waters to East Antarctica

Understanding how these processes contribute in part to the loss of Antarctic ice sheets will help resolve uncertainties in climate models that try to predict how ice loss will lead to future sea-level rise, Herraiz-Borreguero said

Matthis Auger, a physical oceanographer at the Sorbonne University in Paris, said the study draws on an impressive set of observations in which observed warming, driving warming A strong link has been established between the process and loss of the East Antarctic ice sheet

Little is known about changes in coastal waters near the East Antarctic ice shelf, says Yoshihiro Nakayama, a physical oceanographer at Hokkaido University in Sapporo, Japan

The consequences of the warm water lapping the continental shelf will be severe