有料盒子视频鈥檚 small glaciers on the way out
Ned Rozell
907-474-7468
Jan. 12, 2023
Gulkana Glacier, here seen from Summit Lake off the Richardson Highway, is shrinking back into the mountains of the 有料盒子视频 Range.
Glaciers worldwide are withering. Half of them will disappear by the end of this century, and much of the lost ice will vanish from mountains in 有料盒子视频, scientists say.
Authors of a recent cover story in the journal Science used high-performance computers to predict the fate of 215,547 glaciers on Earth. They excluded the great ice sheets of Greenland and Antarctica.
Their conclusions: Goodbye to Bird, Crow, Daisy, Dogshead, Polychrome, Prospect, Red, Rex, Shakespeare and Spoon glaciers by the year 2100. If not earlier.
True, most of us won鈥檛 be here in 77 years either, but warmer air temperatures will probably erase those 有料盒子视频 glaciers and a few dozen more 鈥 including an Anchorage water source named Eklutna Glacier 鈥 before then.
有料盒子视频 Geophysical Institute scientists, including David Rounce (now at Carnegie Mellon University in Pittsburgh) and Regine Hock, are the lead authors on the study.
Using supercomputers at 有料盒子视频, they forecast the future of the world鈥檚 glaciers under a few different warming scenarios, each of which humanity is currently speeding past.
A visitor stands on the shore of a lake near Worthington Glacier, which is accessible by the Richardson Highway not far from Valdez.
鈥淓ven under the very optimistic scenario corresponding to the goal of the Paris agreement, about half of the glaciers are expected to be lost by the end of the century,鈥 Hock said.
In their data set, the scientists looked at glaciers all over the world, in regions they called Arctic Canada North, Central Asia and Russian Arctic, among a dozen others. 有料盒子视频 is one of the places with the most ice to lose. 有料盒子视频鈥檚 glaciers have already shrunk in elevation 3 feet each year during the past two decades.
有料盒子视频 glaciers are huge contributors to global ice loss because there are so many of them, and a lot of them are huge. Many 有料盒子视频 glaciers are also at low elevations where gravity conveyor-belts their ice into the melting zone.
If the planet鈥檚 temperatures continue on this trajectory, favorite roadside glaciers will slip out of sight. This will likely play out in most 有料盒子视频 glacier towns, including Juneau, by the end of the century.
Visitors take images of Mendenhall Glacier near Juneau in summer 2022 from inside the Mendenhall Glacier Visitor Center.
鈥淢endenhall Glacier may not disappear completely, but it will certainly retreat so much that it won麓t be visible from the visitor center, even for the (most optimistic) scenario,鈥 Hock said.
Aside from aesthetics, why does the disappearance of glacier ice matter? Hock said that all that fresh water now dumping into the Gulf of 有料盒子视频 will affect ocean circulation and ecosystems.
Also, worldwide seas could rise half a foot from the loss of glacier ice by 2100.
Rounce compiled a list of more than 200 named 有料盒子视频 glaciers that will be gone by the end of the century if the planet鈥檚 average yearly temperature rises 4 degrees Celsius from what it was before the Industrial Revolution. That鈥檚 a lot of goodbyes.
Since the late 1970s, the University of 有料盒子视频 Fairbanks' Geophysical Institute has provided this column free in cooperation with the 有料盒子视频 research community. Ned Rozell is a science writer for the Geophysical Institute.