Published on Friday, October 25, 2013 by Common Dreams
Beyond Tipping Point: Global Warming Has Raised Arctic Temps to Hottest in 120,000 Years
Citing global warming, new study shows current temps surpass early Holocene period when northern hemisphere was closer to sun
Baffin Island in the Canadian Arctic (Photo: NASA / Michael Studinger)Scientists have long known that climate change is warming the arctic at an alarming rate. But new research shows that in some areas—where human-caused climate change has driven temperatures higher than they've been for tens of thousands of years—melting polar ice caps are now beyond any hope of saving.
A study announced this week confirms for the first time that, because of global warming, the average summer temperature over the past 100 years in the Eastern Canadian Arctic is hotter than any other century in the last 44,000 years and likely the hottest over the past 120,000 years.
This means that current temperatures surpass those of the early Holocene period 11,000 years ago, when the northern hemisphere was closer to the sun, receiving 9 percent more energy from it, explained Colorado University at Boulder geological sciences Professor Gifford Miller, lead author of the study.
"The only possible explanation for today's hotter temperatures is global warming," Miller told Common Dreams in a phone interview. "This is the first study to find firm evidence that current arctic temperatures are warmer now than the early Holecene, when the sun was closer and it should have been a warmer time."
Researchers used radiocarbon analysis of clumps of dead moss emerging from a receding ice cap on Baffin Island to evaluate past temperatures, explains a statement about the study released by the University of Colorado. "At four different ice caps, radiocarbon dates show the mosses had not been exposed to the elements since at least 44,000 to 51,000 years ago."
Prior to 50,000 years ago, the earth was in a period of glaciation. Taking that into consideration, scientists concluded that Canadian Arctic temperatures have likely not been at their current warmth for 120,000 years.
The research found that a majority of the earth's warming has happened in the past 20 years. "All of Baffin Island is melting," said Miller in a statement. "And we expect all of the ice caps to eventually disappear, even if there is no additional warming,"
Holocene
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