Ice Apocalypse

Ice Apocalypse

SOURCE: Grist DATE: November 21, 2017 SNIP: The glaciers of Pine Island Bay are two of the largest and fastest-melting in Antarctica. (A Rolling Stone feature earlier this year dubbed Thwaites “The Doomsday Glacier.”) Together, they act as a plug holding back enough ice to pour 11 feet of sea-level rise into the world’s oceans — an amount that would submerge every coastal city on the planet. For that reason, finding out how fast these glaciers will collapse is one of the most important scientific questions in the world today. In the past few years, scientists have identified marine ice-cliff instability as a feedback loop that could kickstart the disintegration of the entire West Antarctic ice sheet this century — much more quickly than previously thought. A wholesale collapse of Pine Island and Thwaites would set off a catastrophe. Giant icebergs would stream away from Antarctica like a parade of frozen soldiers. All over the world, high tides would creep higher, slowly burying every shoreline on the planet, flooding coastal cities and creating hundreds of millions of climate refugees. All this could play out in a mere 20 to 50 years — much too quickly for humanity to adapt. “It could happen faster or slower, I don’t think we really know yet,” says Jeremy Bassis, a leading ice sheet scientist at the University of Michigan. “But it’s within the realm of possibility, and that’s kind of a scary thing.” There’s a recurring theme throughout these scientists’ findings in Antarctica: What we do now will determine how quickly Pine Island and Thwaites collapse. A fast transition away from fossil fuels...
Venezuela is losing its last glacier

Venezuela is losing its last glacier

SOURCE: EarthSky Voices DATE: November 19, 2017 SNIP: Venezuela used to have five glaciers. Today, only one remains. The last glacier in Venezuela, the Humboldt glacier, is about to disappear. Once Venezuela loses the Humbolt, it will become the first country in modern history to have lost all of its glaciers. The glacier is expected to completely vanish in ten to twenty years, and scientists have expressed the importance of studying the glacier in its last...
‘Impossible To Save’: Scientists Are Watching China’s Glaciers Disappear

‘Impossible To Save’: Scientists Are Watching China’s Glaciers Disappear

SOURCE: NPR DATE: October 21, 2017 SNIP: Li scrambles over a frozen ridge and heads toward a lone pole wedged in the ice. Clouds emerge from a peak above and quickly blow past. He stops to catch his breath. He is at 14,000 feet. The snow is thick. The air is thin. “This is called a sight rod,” he says, grasping the pole. “We come up here each month to check it, to see how fast the glacier’s melting. Each year, the glacier is 15 feet thinner.” In the past 50 years, says Li, the average global temperature has risen by 1 degree Celsius (1.8 degrees Fahrenheit). As a result, these glaciers — split from the original Tianshan No. 1 glacier into No. 1 East and No. 1 West — are retreating by around 30 feet each year. At the rate global temperatures are rising, some 55 percent of all the glaciers in Xinjiang — nearly 11,000 — will be gone within 50 years. “Even if global temperatures stop rising, this glacier will continue to melt,” says scientist Li, atop the Tianshan No. 1 East glacier. “So, no, it’s impossible to save...
Warm waters tripled the amount of ice lost in these Antarctic glaciers — and that’s bad for sea level rise

Warm waters tripled the amount of ice lost in these Antarctic glaciers — and that’s bad for sea level rise

SOURCE: The Verge DATE: September 26, 2017 SNIP: Between 2008 and 2012, warmer than usual waters caused four glaciers in Western Antarctica to flow toward the sea faster than any other glacier on the continent. The glaciers also lost more than three times the amount of ice than usual, according to new research. All these changes are bad news for Antarctica — and us. As grounded glaciers melt, sea levels around the world rise. Researchers at NASA’s Jet Propulsion Laboratory (JPL) found that 1 to 2 degrees Fahrenheit warmer than usual waters in the area doubled the glaciers’ speed toward the sea, and more than tripled the amount of ice they lost — up to 33 feet a year, from 7 to 10 feet a year. Today’s study is the first one to show that warmer waters aren’t just affecting floating ice — they’re already also causing melting in those grounded glaciers that have the potential to raise sea levels, says study co-author Catherine Walker, a NASA postdoctoral fellow at JPL. “This is the first time that we could see something directly affecting glaciers that are on land, that are in contact with the ocean but not floating,” Walker tells The...
As ice thaws, rock avalanches on Southeast Alaska mountains are getting bigger

As ice thaws, rock avalanches on Southeast Alaska mountains are getting bigger

SOURCE: Alaska Dispatch News DATE: September 19, 2017 SNIP: A study of rock avalanches in the western part of Glacier Bay National Park and Preserve found that the likelihood of large slides covering about 2 square miles has at least doubled in the last five years. As the climate has warmed, characteristics of the region’s rock avalanches have changed, says the study, published in Landslides, the journal of the International Consortium on Landslides. “They’re bigger, and they’re traveling farther,” said lead author Jeffrey Coe, a U.S. Geological Survey landslide expert based in Colorado. The likely reason, says the study, is thaw of the ice that fills the mountains’ rock cracks, crevices and fractures, referred to as “rock-permafrost,” abetted by melt of the region’s glaciers and the particular structures of the slopes. The rock-permafrost helps hold steep slopes intact, so thaw or even softening of that ice destabilizes the rock, Coe said. “You can get ice degradation below freezing,” he said. Glacial thinning is likely a secondary factor, he said. Thinned glaciers are less effective at propping up mountain faces, he said. “In many places, you have a de-buttressing effect of the ice loss,” he said. The study correlates the increasing size of Glacier Bay rock avalanches to a long-term warming trend. The large avalanches began about two years after the area’s annual maximum temperature shifted above freezing, the study points...