While Alaska’s glaciers and ice fields are dwarfed by the huge ice sheets of Antarctica, or even Greenland, they play a disproportionate role in the rise of sea levels, said Shad O’Neel, a glacier researcher with the U.S. Geological Survey.
“Glaciers are an important player, even though they’re not that big,” he said. “That means they’re changing more rapidly than the ice sheets” of Antarctica and Greenland.”
O’Neel spoke at the University of Alaska Southeast’s Evening at Egan forum Friday. The school’s Department of Environmental Science brought him to Juneau.
O’Neel said he was impressed to see such a large turnout, given the competition of the World Series deciding game, but attributed it to the increasing interest in the issue of climate change.
For O’Neel, studying glaciology, first with a master’s at the University of Alaska Fairbanks and then a Ph.D. at the University of Colorado Boulder, was an interesting academic field, with some added fun of getting out into the mountains.
“It was engaging mentally, and while I didn’t feel like I was doing much harm, I wasn’t giving much back to society either,” O’Neel said.
Now, however, O’Neel and his colleagues are being asked to answer crucial question about glaciers’ role in sea level rise.
What they’re finding is that the glaciers are playing a more important role than their size would suggest, but that role and even how they operate are only just beginning to be understood.
Lower elevation glaciers, especially those that reach tidewater, are diminishing, but higher elevation glaciers, especially those fed by accumulation basins getting lots of snow are maintaining or even growing.
“The glaciers that don’t have those basins are wasting away,” O’Neel said.
Not all the glaciers are diminishing, and scientists are studying those few that are advancing and growing trying to learn more about how glaciers operate.
“One of the things that’s most interesting about Alaska is that we have a lot of glaciers that are bucking the trend,” he said. “Well, not a lot, but we have some outliers,” he said.
Not all the glaciers that are advancing are actually growing. Some are losing mass or thickness, but are advancing sometimes rapidly.
One of those is Icy Bay, near Yakutat.
“Some are doing really strange things,” he said. “Icy Bay is advancing and losing mass at the same time.”
Some of those advancing glaciers are adding huge volumes of water that was formerly locked in ice into the oceans, but even glaciers where the face is retreating are flowing towards the ocean and contributing to sea level rise.
“Glacier ice plays an integral role as climate is changing around the globe,” he said.”
Figuring out what role climate change plays in an individual glacier’s decline is difficult, he said. That’s true even when there is dramatic change, he said, pointing to a Glacier Bay glacier, which no longer exists.
“This glacier is gone, there’s no question about it,” he said. “The real question is, is that related to climate or is there some other process that’s important?” he said.
What’s happening with Alaska’s glaciers, climate’s role in those changes, and what that means for the future are questions they’re trying to find answers to at the U.S. Geological Survey’s Alaska Science Center in Anchorage, he said.
“Glaciers are always changing, the connection to climate requires care, that’s one of my messages I want to get out,” O’Neel said.
• Contact reporter Pat Forgey at 523-2250 or at email@example.com.