A new study published in the Journal Nature Climate Change shows that “zombie ice” could increase the previously predicted sea level rise by up to 10 inches or more. “Zombie ice,” which refers to dead ice melting, is going to make sea level rise worse in the coming years. The Intergovernmental Panel on Climate Change (IPCC) had previously warned that climate change could result in two to five inches of sea level rise by 2100.
“It’s dead ice. It’s just going to melt and disappear from the ice sheet,” said study co-author William Colgan, a glaciologist at the Geological Survey of Denmark and Greenland (GEUS).”This ice has been consigned to the ocean, regardless of what climate (emissions) scenario we take now.”
According to the researchers behind the study, we can think of zombie ice as an “ice budget deficit” that occurs due to a reduction in snow. Naturally, snowfall usually compensates for the ice loss that occurs when ice sheets melt. But climate change has reduced the occurrence of snow thanks to greenhouse gas effects since the 1980s. As a result, this deficit has to be accounted for in the sea level rise.
The study further claims that the estimated 10 inches in sea level rise are just the bare minimum. The researchers say, if nothing is done to make this better, the rise could be as much as 30 inches. Working by their provided minimum ice loss, approximately 120 trillion tons of water will melt off the Greenland ice sheet. That is sufficient water to cover the whole of the U.S. to 37 feet.
According to NASA, some parts of Greenland such as the northwestern are experiencing up to eight billion tons of ice loss per year. The situation gets much worse in Northern Greenland where up to 29 billion tons of ice are lost per year since the 2000s. While the southeastern and southwestern regions are still quite low in terms of ice loss, these numbers should be a cause for alarm.
“If you look at climate model projections, we can expect to see larger areas of the ice sheet experiencing melt for longer durations of the year and greater mass loss going forward,” said University of Georgia ice scientist Tom Mote, as reported by AP. “There’s every reason to believe that years that look like this will become more common.”
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