A U.S. government agency predicted the melting of the polar ice cap in the year 2030. However, climate guru Al Gore said at the U.N. climate conference on Monday that new computer modeling indicates this could happen as soon as 2014.
One U.S. government scientist on Monday said the new prediction was too severe, but other researchers have previously projected a quicker end than 2030 to the Arctic summer ice cap.
Former U.S. Vice President Gore said, “It is hard to capture the astonishment that the experts in the science of ice felt when they saw this.”
Gore and a group of Scandinavian officials and scientists have come together for the two-week conference.
The group presented two new reports updating fast-moving developments in Antarctica, the autonomous Danish territory of Greenland, and the rest of the Arctic.
Denmark’s foreign minister, Per Stig Moeller, said, “The time for collective and immediate action on climate change is now.”
But delegates from 192 nations were bogged down in disputes over key issues. This further dimmed hopes for immediate action to cut more deeply into global emissions of greenhouse gases.
Gore and Danish ice scientist Dorthe Dahl Jensen clicked through two slide shows for a standing-room-only crowd of hundreds in a side event at the Bella Center conference site.
One report, on the Greenland ice sheet, was issued by the Arctic Monitoring and Assessment Program, an expert group formed by eight Arctic governments, including the United States. The other, commissioned by Gore and Norway’s government, was compiled by the Norwegian Polar Institute on the status of ice melt worldwide.
In the past century, Average global temperatures have increased 0.74 degrees C (1.3 degrees F) but the mercury has risen at least twice as quickly in the Arctic.
Scientists say the makeup of the frozen north polar sea has shifted significantly in recent years as much of the thick multiyear ice has given way to thin seasonal ice.
In September 2007, the Arctic ice cap dwindled to a record-low minimum extent of 4.3 million square kilometers. The melting in 2008 and 2009 was not as extensive, but still ranked as the second- and third-greatest decreases on record.
the U.S. National Oceanic and Atmospheric Administration predicted last April that Arctic summers could be almost ice-free within 30 years, not at the 21st century’s end as earlier predicted.
Gore cited new scientific work at the U.S. Naval Postgraduate School, whose Arctic ice research is important for planning polar voyages by Navy submarines. The computer modeling there stresses the “volumetric,” looking not just at the surface extent of ice but its thickness as well.
Gore said, “Some of the models suggest that there is a 75 percent chance that the entire north polar ice cap during some of the summer months will be completely ice-free within the next five to seven years.”
His office later said he meant nearly ice-free, because ice would be expected to survive in island channels and other locations.
Mark Serreze, of the U.S. National Snow and Ice Data Center in Boulder, Colorado, said, “It’s possible but not likely. We’re sticking with 2030.”
On the other hand, a leading NASA ice scientist, Jay Zwally, said last year that the Arctic could be essentially ice-free within “five to less than 10 years.”
Meanwhile, what’s happening to Greenland’s titanic ice sheet “has really surprised us,” said Jensen of the University of Copenhagen.
She cited one huge glacier in west Greenland, at Jakobshavn, that in recent years has doubled its rate of dumping ice into the sea. Between melted land ice and heat expansion of ocean waters, the sea-level rise has increased from 1.8 millimeters a year to 3.4 millimeters (.07 inch a year to .13 inch) in the past 10 years.
Jensen said the biggest ice sheets “” in Greenland and West Antarctica “” were already contributing 1 millimeter (.04 inch) a year to those rising sea levels. She said this could double within the next decade.
“With global warming, we have woken giants,” she said.
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