Melting rate of Antarctic glaciers linked to global sea level rise

Scientists in Antarctica say they've measured ice melting below a massive glacier considered the biggest source of uncertainty in global sea level projections. Researchers have been studying the huge Pine Island glacier to analyze how quickly warm water has been melting the massive glacier from beneath. "Intensive melting under the Pine Island ice shelf, as observed in our study, could potentially lead to the speed up and ultimate break-up of the ice shelf," study co-author David Holland of New York University said. "That's important, as this ice shelf is currently holding back inland ice, and without that restraining force, the Pine Island catchment basin could further contribute to global sea-level rise." Scientists have long known a flow of warm sea water has been melting the Pine Island Glacier from below the 30-mile-long floating ice shelf at the outer reaches of the glacier field. The researchers drilled through 1,600 feet of solid ice to lower sensors into the water below to measure the rate of the glacier's melting, currently at more than 2 inches per day, a university release reported Thursday. "What we have brought to the table are detailed measurements of melt rates that will allow simple physical models of the melting processes to be plugged into computer models of the coupled ocean/glacier system," Tim Stanton of the Naval Postgraduate School in Monterey, Calif., said. "These improved models are critical to our ability to predict future changes in the ice shelf, and glacier-melt rates of the potentially unstable Western Antarctic Ice Sheet in response to changing ocean forces." Melting underneath massive glaciers is seen as significantly contributing to global sea-level rise now and into the future, the researcher said.