Eideard

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.

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 meters (187 ft) if it ever all melted. Even a tiny thaw at the fringes could swamp coasts from Bangladesh to Florida…

West Antarctica’s thaw accounts for 10 percent 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…

Adrian Jenkins, lead author at BAS, said the study raised “new questions about whether the current loss of ice from Pine Island Glacier is caused by recent climate change or is a continuation of a longer-term process that began when the glacier disconnected from the ridge.”

Research that provides more data, better directed conclusions is always welcome. Welcomed, that is, by scientists and those who would make decisions about life and politics based on scientific understanding.