According to a new study, a critical Antarctic glacier is becoming more vulnerable as satellite images show the ice shelf that prevents it from collapsing into the sea is breaking up much faster than previously and spawning massive icebergs.
The Pine Island Glacier's ice shelf loss accelerated in 2017, raising concerns among scientists that, due to climate change
, the glacier's collapse could occur sooner than the many centuries predicted. The floating ice shelf acts as a cork in a bottle for the rapidly melting glacier, preventing its much larger ice mass from flowing into the ocean
According to a study published in the journal Science
Advances on Friday, the ice shelf retreated by 12 miles (20 kilometers) between 2017 and 2020. The crumbling shelf was captured on time-lapse video by a European satellite that takes pictures every six days.
“You can see stuff just tearing apart,” said study lead author Ian Joughin, a glaciologist at the University
. “It almost looks like the speed-up itself is weakening the glacier.... And we’ve lost maybe 20% of the main shelf so far.”
There were three large breakup events between 2017 and 2020, resulting in icebergs more than 5 miles (8 kilometers) long and 22 miles (36 kilometers) wide, which then split into many smaller pieces, according to Joughin, as well as numerous smaller breakups.
“It's not inconceivable that the entire shelf could give way and fall apart within a few years,” Joughin said, adding that it's a long shot, but not a very long shot.
Beginning in 2017, Joughin tracked two points on the main glacier and discovered that they were moving
12% faster toward the sea.
“So that means 12% more ice from Pine Island is entering the ocean that wasn’t there before,” he explained.
The Pine Island Glacier, which is not located on an island and does not have pine trees, is one of two side-by-side glaciers
in western Antarctica
that ice scientists are most concerned about losing, the other being the Thwaites Glacier.
Pine Island contains 180 trillion tons of ice, the equivalent of 1.6 feet (half a meter) of sea level rise, and accounts for roughly a quarter of the continent's ice loss.
“Pine Island and Thwaites are our biggest concern right now because they are collapsing, and the rest of West Antarctica will follow,” said Isabella Velicogna, an ice scientist at the University of California
, Irvine, who was not involved in the study.
While ice loss is a result of climate change, Joughin believes there was no unusual extra warming in the region that caused this acceleration.
“These scientific findings continue to highlight Antarctica’s vulnerability as a major reservoir
for potential sea level rise,” said Twila Moon, a National Snow and Ice Data scientist who was not involved in the study. “Other research
has confirmed that how Antarctica evolves in the future will be dependent on human greenhouse gas emissions