Antarctic Ice shelves propping up two major glaciers are breaking up


CLOSE

NASA images of Antarctica’s Thwaites Glacier show how it has fractured into smaller pieces over the past 10 years.

Buzz60

Story Highlights

  • The loss of the Thwaites glacier could trigger the broader collapse of the West Antarctic ice sheet.
  • Ice shelves are the gatekeepers for glaciers flowing from Antarctica toward the ocean.
  • “These images to me indicate that these ice shelves are in a very bad state.”

Two of Antarctica’s most important glaciers are breaking free from their restraints, a new study reports. 

This potentially has major consequences for rising sea levels around the world.

The Pine Island and Thwaites glaciers, which sit side-by-side in West Antarctica on the Amundsen Sea, are among the fastest-changing glaciers in the region, already accounting for 5% of global sea-level rise, CNN said.

The Thwaites glacier is of particular concern: The loss of the glacier could trigger the broader collapse of the West Antarctic ice sheet, which contains enough ice to eventually raise seas by about 10 feet, the Washington Post said. 

In the study, researchers combined satellite imagery from various sources to gain a more accurate picture of the rapid development of damage to portions of the ice shelves of Pine Island and Thwaites. 

Ice shelves are permanent floating sheets of ice 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, glacial ice enters the ocean faster and accelerates the pace of global sea-level rise.

According to the study, the damage consists of crevasses and fractures in the glaciers, the first signs of the weakening process. Modeling has revealed that the emergence of this kind of damage 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 that 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,” study lead author Stef Lhermitte of Delft University of Technology in the Netherlands told the Washington Post. 

“We knew they were sleeping giants and these were the ones losing a lot of miles (of ice), but how far and how much still remains a large uncertainty,” Lhermitte said to CNN. “These ice shelves are in the early phase of disintegration, they’re starting to tear apart.”

More: Antarctica’s new record high temperature: Is it climate change?

By the end of the century, global sea level is likely to rise at least one foot above 2000 levels, even if greenhouse gas emissions follow a relatively low pathway in coming decades, the National Oceanic and Atmospheric Administration said. 

How much it will rise depends mostly 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. 

Read or Share this story: https://www.usatoday.com/story/news/nation/2020/09/15/antarctic-ice-shelves-propping-up-two-major-glaciers-breaking-up/5804020002/



Sahred From Source link World News

Be the first to comment

Leave a Reply

Your email address will not be published.


*