Granny says it's `cause o' dat global warmin'...

More of Antarctic glacier floating than thought: scientists
Wed, Mar 21, 2018 - More of a France-sized glacier in Antarctica is floating on the ocean than previously thought, scientists said yesterday, raising fears it could melt faster as the climate warms and have a dramatic effect on rising sea levels.
The Totten Glacier is one of the fastest-flowing and largest glaciers in Antarctica, with scientists keen to keep a close eye on how it melts given the enormous amount of water it could potentially unleash. Using artificially created seismic waves that help scientists see through the ice, researchers have discovered that more of the Totten Glacier floats on the ocean than initially thought. “In some locations we thought were grounded, we detected the ocean below indicating that the glacier is in fact floating,” said Paul Winberry from Central Washington University, who spent the summer in Antarctica studying the Totten.

The findings are important, because recent studies have shown that the Totten Glacier’s underbelly is already being eroded by warm sea water flowing hundreds of kilometers inland after passing through underwater “gateways.” As it does, the portion of the glacier resting on water rather than rock increases, accelerating the pace of disintegration. Winberry said more of the glacier floating on a warming ocean could help explain recent periods of accelerated melting. “It also means the Totten might be more sensitive to climate variations in the future,” he added.

Glaciers are huge bodies of dense ice that slowly move down valleys, mountains and slopes under their own weight over many centuries, sculpting the earth below as they go. According to NASA monitoring, between 2002 and 2016, Antarctica lost 125 gigatonnes of ice per year, causing sea levels worldwide to rise by 0.35mm annually.

Team leader Ben Galton-Fenzi, from the Australian Antarctic Division, said the glacier contains enough ice to raise global sea levels by about 3m if it all melted. “Since the 1900s the global sea level has risen by around 20cm and by the end of the century it’s projected to rise by up to 1m or more, but this is subject to high uncertainty, which is why studying glaciers, such as the Totten, is important,” he said.

http://www.taipeitimes.com/News/worl.../21/2003689745