Another Arctic summer brings researchers from around the world to Alaska, and those studying glaciers are finding reason to worry about the future of big ice in a warming world.
From The Redoubt Reporter comes a lengthy look at the findings of UAF researcher Martin Truffer, who's been doing radio-wave surveys of the Kenai Peninsula's Harding Icefield for three years.
“The ice field essentially is thinning in almost all places,” said Truffer. In some spots, the thinning has been measured at minus 3.5 meters annually.
“That’s about 10 to 12 feet of elevation change per year — about the size of this room of elevation drop every year, averaged over the last 50 years. These are really large changes,” Truffer [said].
But there are still places on the icefield where snow on top survives through summer, an indication that while the bottom of the icefield is melting out at a faster pace, some ice mass is still being added on top. But the current trend can't continue indefinitely.
“If you start seeing a lot of exposed ice on the ice field itself at higher elevations, then that’s bad because that means it’s going to thin and it’s going to increase thinning over time. … If the ice field still has snow from last winter then, for the moment, the ice field is still OK,” he said.
Joseph Blumberg of Dartmouth College writes in Alaska Dispatch of drilling this summer on a Mount Hunter glacier. Scientists hope ice cores hundreds of feet long removed from the glacier will give them a better idea of how fast Alaska Range glaciers will retreat.
“What is neat about this project is that we are using ice core data and combining it with this very different sort of data to get a complete picture of not just how the climate in central Alaska changed in the past, but how the glaciers responded,” [researcher Erich] Osterberg says.
In Southeast Alaska, the massive Bering Glacier is thinning at an average rate of 2 feet per year, retired USGS glaciologist Wendell Tangborn tells SITnews.