Warm Ocean Water Melting Antarctic Glaciers From Below; Can Eat Away 2 Inches A Day
Sep 13, 2013 01:43 PM EDT
A new study found warm water is melting Antarctica's glaciers from below.
The research team recorded how water has been degrading the bottom of the 31-mile-long Pine Island Glacier, which "regulates the seaward movement of a portion of the West Antarctic Ice Sheet (WAIS)," a National Science Foundation press release reported. WAIS contains an impressive 10 percent of Antarctica's ice.
The glacier is extremely secluded, and sits in the midst of treacherous terrain and sporadic weather, making it extremely hard to study. Research teams were expected to set up camp there as early as 2007, but were only able to establish three drilling camps in 2012.
"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's Department of Oceanography, who participated in the study, 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," he said.
Scientists have known there was relatively warm water eating away at the ice's underside since the 1980s. This study was able to pinpoint "the mechanism by which the melting occurs."
"Fresh water forms every time [the sea] injects heat into the shelf," Stanton said. "The warm water starts to melt the ice at the grounding line and creates a buoyant plume called a boundary layer current. We measured the effects of that current for the first time."
The measured melt rated varied but went as high as two inches per day in the channel. On the "flanks" of the ice there was only no melting.
The researchers believe it is critical to gain a better understanding of "channelized melting" in order to gain insight into rising global sea levels.
Recently, a giant peice of ice the size of Chicago broke off from the Pine Island Glacier.