Posted by: Saving Water SA (Cape Town, South Africa) - partnered with Water Rhapsody conservation systems – 21 June 2010

A yellow submarine has helped to solve a puzzle about one of Antarctica’s fastest-melting glaciers, adding to concerns about how climate change may push up world sea levels, scientists say.

Pine Island Glacier. Photo by Tom Kellogg - 1985.

The robot submarine, deployed under the ice shelf floating on the sea at the end of the Pine Island Glacier, found that the ice was no longer resting on a subsea ridge that had slowed the glacier’s slide until the early 1970s.

Antarctica is key to predicting the rise in sea levels caused by global warming — it has enough ice to raise sea levels by 57 metres (187 ft) if it ever all melted. Even a tiny thaw at the fringes could swamp coasts from Bangladesh to Florida.

The finding from the 2009 mission “only adds to our concern that this region is indeed the ‘weak underbelly’ of the West Antarctic Ice Sheet”, co-author of the study Stan Jacobs at the Lamont-Doherty Earth Observatory said in a statement.

West Antarctica’s thaw accounts for 10% of a recently observed rise in sea levels, with melting of the Pine Island glacier quickening, especially in recent decades, according to the study led by the British Antarctic Survey (BAS) and published in the journal Nature Geoscience.

Loss of contact with the subsea ridge meant that ice was flowing faster and also thawing more as sea water flowed into an ever bigger cavity that now extended 30 km beyond the ridge.

The water was just above freezing at 1 degree Celsius (33,80F). Continue reading Antarctic thaw clues increase concerns