Faster movement of glacier predicted

NEW YORK, Oct. 26 (UPI) -- An Antarctic glacier being watched for its potential to raise global sea levels as the planet warms could speed up its retreat within 20 years, researchers say.

Researchers at Columbia University said the fast-flowing Thwaites Glacier is expected to speed up once it detaches from an underwater ridge that is currently holding it back.

The ridge off west Antarctica that appears to be slowing the glacier's slide into the sea is 2,200 feet tall with two peaks, one currently anchoring the glacier and another farther from shore that held the glacier in place between 55 and 150 years ago, the researchers said.

The finding that the glacier is losing its grip on a previously unknown ridge explains why the glacier seems to be moving faster than it used to, they said.

"Knowing the ridge is there lets us understand why the wide ice tongue that used to be in front of the glacier has broken up," researcher Robin Bell of Columbia's Lamont-Doherty Earth Observatory said. "We can now predict when the last bit of floating ice will lift off the ridge. We expect more ice will come streaming out of the Thwaites Glacier when this happens."