A November 13, 2013 image shows that a new iceberg has broken off Pine Island Glacier and is moving away from the coast. (Photo: U.S. Geological Survey)An Antarctic glacier is melting “irreversibly,” offering “a striking vision of the near future,” a new study shows.
The study published Sunday in the journal Nature Climate Change looked at Pine Island Glacier, the largest single contributor to sea-level rise in the Antarctic.
The team of scientists used three ice flow models to look at the glacier’s grounding line, which separates the grounded ice sheet from the floating ice shelf.
The grounding line, which has already retreated by about 10 kilometers in the last decade, “is probably engaged in an unstable 40â€‰kilometer retreat,” the study finds.
The glacier “has started a phase of self-sustained retreat and will irreversibly continue its decline,” said Gael Durand, a glaciologist with France’s Grenoble Alps University and study co-author.
Durand says the findings show “a striking vision of the near future. All the models suggest that [the glacier’s] recession will not stop, cannot be reversed and that more ice will be transferred into the ocean.”
Agence France-Presse adds:
A massive river of ice, the glacier by itself is responsible for 20 per cent of total ice loss from the West Antarctic Ice Sheet today.
On average, it shed 20 billion tonnes of ice annually from 1992-2011, a loss that is likely to increase up to and above 100 billion tonnes each year, said the study.
“The Pine Island Glacier shows the biggest changes in this area at the moment, but if it is unstable it may have implications for the entire West Antarctic Ice Sheet,” Planet Earth Online reports study co-author G. Hilmar Gudmundsson from the National Environment Research Council’s British Antarctic Survey as saying.
“Currently we see around two millimeters of sea level rise a year, and the Pine Island Glacier retreat could contribute an additional 3.5 – 5 millimeters in the next twenty years, so it would lead to a considerable increase from this area alone. But the potential is much larger,” Gudmundsson warned.
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Source: Common Dreams