An Antarctic glacier the size of Florida is on the verge of collapse, scientists with the American Geophysical Union warned Monday, a nightmare scenario made worse by climate change that could eventually result in several feet of global sea level rise.
The findings were based on new satellite imagery of the Thwaites Glacier, which has been nicknamed the “doomsday glacier,” showing a proliferation of cracks across its surface.
“The eastern ice shelf is likely to shatter into hundreds of icebergs,” Oregon State University glaciologist Erin Pettit said at a video news conference Monday. “Suddenly the whole thing would collapse.”
Scientists have been monitoring the glacier, the current melting of which contributes to roughly 4 percent of annual sea level rise, for years. Its eastern portion abuts an underwater mountain, and was thought to be more stable, but new satellite images revealed that fractures have developed that are allowing warming ocean waters to speed its disintegration.
If the eastern portion of the glacier were to give way, it would hasten the collapse of its other portions, Pettit said, adding that the collapse of the eastern section could occur in the next three to five years, “like the shattering of your car’s window.”
“As it’s structured right now, this ice shelf acts like a dam. But it’s not going to for very long,” Pettit said.
The chain reaction following the collapse of the eastern section of the glacier could threaten coastal residents around the world, many of whom may be unprepared for a sudden spike in sea level, which has risen slowly due to climate change since the dawn of the Industrial Revolution. Since 1880, rising global temperatures have resulted in 8 to 9 inches of sea level rise, though the rate of rise has seen a sharp uptick in recent decades. By 2100, NASA predicts, climate change will cause seas to rise by 2 to 6 feet, largely because of the melting of ice in Antarctica and Greenland.
The Thwaites Glacier has been melting due to a combination of warm air and water temperatures, caused at least partly by climate change, making it more unstable. Between the 1980s and 2017, it lost 600 billion tons of ice. As the oceans continue to warm, the glacier is expected to become more unmoored to land, increasing its risk of collapse.
“Things are evolving really rapidly here,” Ted Scambos, a glaciologist at the University of Colorado Boulder, said during Monday's news conference. “It’s daunting.”
While it could take centuries for the full impact of a total collapse of the Thwaites Glacier to play out, the latest data from Antarctica is not giving scientists any reason for optimism.
”Each new satellite image we get, we see deeper and longer fractures,” Pettit said, adding, “What we’re seeing already is enough to be worried about. Thwaites is kind of a monster.”