The Big Melt: Arctic Sea Ice At Record Low
Thursday, August 30, 2012
Ian Eisenman, Assistant Professor of Climate Science and physical oceanography at Scripps Institution of Oceanography, his research is on sea ice.
Somewhere amidst the news this week about the Republican Convention and Hurricane Isaac, there was a less-reported phenomenon that may end up being the biggest news of all. Research scientists report that the level of Arctic sea ice has reached a new recorded low.
Even though it's nearly a month before Arctic sea ice usually reaches its minimum, the August 26, 2012 recording appears to be the lowest ever, according to the National Snow and Ice Data Center. That means sea ice is expected to continue to diminish until the middle of September. The previous low was observed on September 18, 2007.
And although the Arctic summer has not been especially warm, the region has lost more sea ice this year than in any time since records started in 1979.
Ian Eisenman, an assistant professor of climate science and physical oceanography at Scripps Institution of Oceanography who researches sea ice, told KPBS this amount of loss is surprising. He said the amount of sea ice ebbs and flows from year to year, but that there's a "strong downward trend" in summer sea ice minimums.
Eisenman said melting sea ice contributes to the "ice-albedo feedback," a vicious cycle that further perpetuates climate change.
While snow and ice are good at reflecting sunlight, the ocean is not, he said. So when there's less ice and more ocean, less sunlight is reflected, which leads to further warming and then even more sea ice melt.
"So it's easy to imagine how this could lead to some sort of runaway effect," he said.
But, he said, ice isn't the only player in the Arctic system, so other factors could work to balance out the ice melt.
Eisenman said the news about the sea ice means scientists may have to revise their climate models.
He said the "few dozen state-of-the-art global models" say we should be losing less ice than we actually are.
"This one year added to the record shows that the long-term ice loss is even faster when you add that year, so the models do a little worse now," he said.
Claire Trageser contributed to this report.
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