Pine Island Glacier is one of the biggest routes for ice to flow from Antarctica into the sea. The floating ice shelf at the glacier’s tip has been melting and thinning for the past four decades, causing the glacier to speed up and discharge more ice.
Understanding this ice shelf is a key for predicting sea-level rise in a warming world. A paper published Jan. 2 in the advance online version of the journal Scienceshows that the ice shelf melting depends on the local wind direction, which is tied to tropical changes associated with El Niño. (more…)
Narrow stripes of dirt and rock beneath massive Antarctic glaciers create friction zones that slow the flow of ice toward the sea, researchers at Princeton University and the British Antarctic Survey have found. Understanding how these high-friction regions form and subside could help researchers understand how the flow of these glaciers responds to a warming climate.
Just as no-slip strips on flooring prevent people from slipping on a wet floor, these ribs or “tiger stripes” — named in reference to Princeton’s tiger mascot — provide friction that hinders the glaciers from slipping along the underlying bed of rock and sediment, the researchers report online in the journal Science. (more…)
ANN ARBOR — In events that could exacerbate sea level rise over the coming decades, stretches of ice on the coasts of Antarctica and Greenland are at risk of rapidly cracking apart and falling into the ocean, according to new iceberg calving simulations from the University of Michigan.
“If this starts to happen and we’re right, we might be closer to the higher end of sea level rise estimates for the next 100 years,” said Jeremy Bassis, assistant professor of atmospheric, oceanic and space sciences at the U-M College of Engineering, and first author of a paper on the new model published in the current issue of Nature Geoscience. (more…)
AUSTIN, Texas — Using ice-penetrating radar instruments flown on aircraft, a team of scientists from the U.S. and U.K. have uncovered a previously unknown sub-glacial basin nearly the size of New Jersey beneath the West Antarctic Ice Sheet (WAIS) near the Weddell Sea. The location, shape and texture of the mile-deep basin suggest that this region of the ice sheet is at a greater risk of collapse than previously thought.
Team members at The University of Texas at Austin compared data about the newly discovered basin to data they previously collected from other parts of the WAIS that also appear highly vulnerable, including Pine Island Glacier and Thwaites Glacier. Although the amount of ice stored in the new basin is less than the ice stored in previously studied areas, it might be closer to a tipping point. (more…)
*Researchers study heat delivered by ocean currents to bottom side of glacier that releases more than 19 cubic miles of ice each year*
An international team of researchers, funded by the National Science Foundation (NSF) and NASA, will helicopter onto the Pine Island Glacier ice shelf, one of Antarctica’s most active, remote and harsh spots, in mid-December 2011–weather permitting.
The project’s mission is to determine how much heat ocean currents deliver to the underside of the Pine Island Glacier as it discharges into the sea. Quantifying this heat and understanding how much melting it causes is key to developing reliable models to predict glacier acceleration and therefore predict how much ice will be delivered from land into the ocean thus contributing to sea level rise. (more…)
