Antarctic ice melt and climate change will contribute to rising sea levels around the globe over the next 150 years. Antarctica’s Thwaites Glacier is the at the forefront of the dire warning as it slowly crumbles away into the Atlantic Ocean. Scientists who have studied this rapidly deteriorating part of Antarctica fear Thwaites’ “instability” will continue without additional global warming. And if the Florida-sized glacier disintegrates into the ocean, sea levels are expected to rise by 1.64ft (50cm).
The findings were presented this week (July 8) by the Georgia Institute of Technology.
Assistant professor Alex Robel, who led the study on Antarctica’s ice melt at Georgia Tech’s School of Earth and Atmospheric Sciences, warned of the consequences.
He said: “If you trigger this instability, you don’t need to continue to force the ice sheet by cranking up temperatures.
“It will keep going by itself and that’s the worry.
“Climate variations will still be important after that tipping point because they will determine how fast the ice will move.”
In the last six years alone, at least five Antarctic glaciers have double the rates at which they are melting.
According to the US National Science Foundation (NSF), satellite imagery has shown worrying signs of ice loss at Thwaites since the 1990s.
The rates have doubled, singling out the Thwaites Glacier as a significant contributor to rising sea levels.
The NSF said in a report Thwaites alone accounts for 10 percent of global sea level rise.
Further NSF studies into the disappearing glacier have found Thwaites poses “the greatest risk of future sea level rise” due to the changes already well underway.
The foundation argued “major, irreversible changes” are possible in the system over the course of decades to centuries.
Helene Seroussi, a NASA scientist who collaborated on the Antarctica study, said: “After reaching the tipping point, Thwaites Glacier could lose all of its ice in a period of 150 years.
“That would make for a sea level rise of about half-a-meter.”
Thwaites Glacier could lose all of its ice in a period of 150 years
Helene Seroussi, NASA Jet Propulsion Laboratory
There is almost eight times as much water locked away in Antarctic ice as there is in Greenland and 50 times as much as all of the world’s mountain glaciers.
As the ice melts and crumbles into the oceans, the amount of present water pushes up on coastal areas, threatening floods around the globe.
By the end of this century, sea levels are expected to rise by up to two feet (60cm).
Professor Robel said: “You want to engineer critical infrastructure to be resistant against the upper bound of potential sea level scenarios a hundred years from now.
“It can mean building your water treatment plants and nuclear reactors for the absolute worst-case scenario, which could be two or three feet of sea level rise from Thwaites Glacier alone, so it’s a huge difference.”
The researchers published their disturbing findings on July 8 in the journal Proceedings of the National Academy of Sciences.
The Antarctic study was funded by the National Science Foundation and space agency NASA.
Source: Read Full Article