Stripes of dust and rock restrict flow of Antarctic glaciers

Stripes crucial to understanding movement of large glaciers in Antarctica Researchers have found stripes of rock and dust, which act like no-slip strips used on floors, that are preventing and slowing the movement of ice from Antarctic glaciers toward the sea. The stripes are providing friction and hindering the flow of this ice over the underlying bedrock and sediment. Researchers from Princeton University and the British Antarctic Survey used mathematical models to locate these ribs, dubbed tiger stripes in reference to Princeton's mascot, which occur in the slippery regions of a glacier.
The researchers studied the Pine Island Glacier and the Thwaites Glacier in West Antarctica, which together contributed about 10 percent of the observed sea-level rise over the past 20 years, despite their small areas. The Pine Island Glacier moves at a velocity of about 1.5 miles per year, according to the researchers.
"The ribs may play an important role in buffering the effects of a warming climate, since they slow the movement of ice that reaches the ocean and contributes to sea-level rise," said Sergienko, an associate research scientist at Princeton. "These changes can happen independently of climate change, too."
Surveying the bottom of the ice is nearly impossible as it is over a mile-and-a-half thick, so the researchers used satellite measurements of the ice velocity and and ground-penetrating radar to detect the topography of the bedrock.The data pointed to the presence of these stripes and validated what Richard Hindmarsh, a scientist at the British Antarctic Survey, theorized years earlier.
Source: UPI