NASA images of Antarctica̵
Two of Antarctica’s most important glaciers are breaking free from their limitations, a new study reports.
This has potentially major consequences for rising sea levels around the world.
Pine Island and Thwaites glaciers, which sit side by side in western Antarctica on the Amundsen Sea, are among the fastest-changing glaciers in the region and already account for 5% of global sea level rise, CNN said.
The Thwaites Glacier is of particular concern: The loss of the glacier could trigger a wider collapse of the West Antarctic ice sheet, which contains enough ice to eventually raise the oceans by about 10 feet, the Washington Post said.
In the study, researchers combined satellite images from different sources to get a more accurate picture of the rapid development of damage to parts of the ice shelves on Pine Island and Thwaites.
Ice shelves are permanent liquid ice sheets that connect to a landmass, such as Antarctica, according to the National Snow and Ice Data Center.
Ice shelves are the gatekeepers for glaciers flowing from Antarctica toward the ocean, according to NASA. Without them, the ice will enter the ocean faster and accelerate the pace of global sea level rise.
According to the study, the damage consists of cracks and fractures in the glaciers, the first signs of the weakening process. Modeling has revealed that the emergence of this type of injury initiates a feedback process that accelerates the formation of even more fractures and weakening.
More: Greenland and Antarctica are now melting six times faster than in the 1990s, accelerating sea level rise
“We already knew these were glaciers that might matter in the future, but these images to me indicate that these ice shelves are in a very bad state,” lead author Stef Lhermitte of Delft University of Technology in the Netherlands told the Washington Post.
“We knew they were sleeping giants, and they were the ones who lost a lot of miles (ice), but how far and how much is still a big uncertainty,” Lhermitte told CNN. “These ice shelves are in the early stages of dissolution, they are starting to tear apart.”
More: Antarctica’s new record high temperature: Is it climate change?
By the end of the century, global sea levels are likely to rise at least one foot above 2,000 levels, although greenhouse gas emissions will follow a relatively low path in the coming decades, the National Oceanic and Atmospheric Administration said.
How much it increases depends mainly on the rate of future carbon dioxide emissions and global warming.
The ice shelf study was published Monday in the Proceedings of the National Academy of Sciences.
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