World’s largest ice sheet threatened by warm water surge
Westerly winds are thrusting warm waters towards the East Antarctic ice sheet, and have thinned the region’s ice masses at alarming rates over recent decades, a study has found.
Scientists say that the research, published in Nature Climate Change on 2 August, also helps to resolve one of the largest uncertainties in projections of future sea-level rise: how vulnerable the East Antarctic Ice Sheet, the world’s largest, is to ocean warming.
Ice shelves float on the ocean, extending from and buttressing continental glaciers that amass to form ice sheets. Unlike ice masses in West Antarctica, which are melting at a staggering rate, the East Antarctic ice sheet was thought to be sheltered from ocean warming by cold, dense seawater that forms on the continental shelf, near ice shelves.
But over the past ten years, data and observations have shown that the East Antarctic ice sheet, too, is under increasing threat from warm salty water, which is melting ice shelves from beneath. Yet past studies have struggled to measure the extent of the warming and pinpoint the processes driving it. [Continue reading…]