A new study found that the rapid glacial melting in Greenland will raise global sea levels more than twice as much as previously forecast.

A phenomenon known as “zombie ice”  will eventually raise global sea level by at least 10.6 inches (27 centimetres), according to a new study.

The term zombie ice refers to doomed ice that is no longer getting replenished by parent glaciers as they are now receiving less snow. Consequently, the doomed ice is rapidly melting from climate change and will eventually and inevitably raise global sea levels.

“It’s dead ice. It’s just going to melt and disappear from the ice sheet,” William Colgan, a glaciologist at the Geological Survey of Denmark and Greenland and co-author of the research said. “This ice has been consigned to the ocean, regardless of what climate (emissions) scenario we take now.”

More than 120 trillion tons (110 trillion metric tons) of Greenland’s ice is unable to replenish and thus set to melt from global warming, one of the authors said. 

The study, published Monday in the journal Nature Climate Change, found that, while a scenario where global sea level rise by about 10 inches is inevitable, it could reach as much as 30 inches (78 centimetres). 

The new prediction is almost twice as much as last year’s report by the Intergovernmental Panel on Climate Change (IPCC) projected: a range of 2 to 5 inches (6 to 13 centimetres) of sea level rise from glacial melting in Greenland by the end of the century.

New satellite data from earlier this year revealed that the melting of Greenland’s massive ice sheet is occurring so rapidly that it is now the main factor in global sea level rise

Research by Polar Portal, a joint project between four Danish government research institutions, found that over the past 20 years, Greenland lost more than 5,100 billion tons (4,700 billion metric tons) of ice, enough to flood the entire United States in 1.5 feet (0.5 metres) of water. 

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