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…)
A mystery in the ocean near Antarctica has been solved by researchers who have long puzzled over how deep and mid-depth ocean waters are mixed.
They found that sea water mixes dramatically as it rushes over undersea mountains in Drake Passage – the channel between the southern tip of South America and the Antarctic continent. Mixing of water layers in the oceans is crucial in regulating the Earth’s climate and ocean currents.
The research provides insight for climate models which until now have lacked the detailed information on ocean mixing needed to provide accurate long-term climate projections. The study was carried out by the University of Exeter, the University of East Anglia, the University of Southampton, the Woods Hole Oceanographic Institution, the British Antarctic Survey and the Scottish Association for Marine Science and is published in the journal Nature. (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…)
U researchers map emperor penguin colonies by satellite
Emperor penguins may be icons of the Antarctic, but they aren’t immune to disturbances in their environment.
As climatic and other changes unfold, emperors may dwindle in numbers. But how to tell, when researchers can’t access all the emperor colonies dotting the Antarctic ice shelves and count heads every year?
