Startling images show melting North Pole turning into a lake -
Dramatic images from an automated webcam scanning the North Pole reveal a lake where solid ice used to be.
“It looks amazing,” Dr. James Morrison of the North Pole Environmental Observatory, told the Star. “It looks like it’s Lake Tahoe or something.”
The devil is in the details, though, if you’re a veteran polar scientist such as Morrison.
What he sees is an incremental sign of the relentless erosion of Arctic sea ice. What he also sees, comparing this with all the other webcam images over the months, is a loss of 30 to 40 centimetres of ice.
Even more telling, Morrison said, is what you can’t see.
Not at the North Pole, but on the Canadian side of the Beaufort Sea, an aerial reconnaissance mission this month spotted an alarming landscape of similar melt ponds riddling the surface.
“The melt ponds have covered the whole surface and melted though north of Alaska in the Beaufort. What we’re seeing on the Canada side is really bad. It’s melted all the way through.”
Melt ponds, even the 50-metre across lakes depicted in by the North Pole observatory wide-angle webcam, are not at all unusual during July at the top of the world.
They are bad for sea ice, however. While the melted ice looks dramatic, it’s the effect of the sun beating down on the half-metre deep lake that has Morrison more worried.
Erosion of sea ice happens at the bottom, under the surface, with less ice building on the foundation because of heat buildup.
“It’s important to compare the two pictures,” he said, referring to the two webcams facing in opposite directions: one showing a lake, one showing ice.
“Just by luck, Webcam 2 ended up in being in the middle of a melt pond.
“But I do think now my estimates might have been a little high” for how much sea ice would survive the summer of 2013.
The Arctic hit a record low for sea ice last summer, cracking a previous low set in 2007. The most pessimistic forecasts for this year from the Arctic Research Consortium peg it even lower.
Scientists, including Morrison, are still adding up the numbers for 2013, however. The range of estimates by the international consortium was 3.2 to 5.9 million square kilometres of ice for September.
By comparison, the June, 2013, median was 4.1 million square kilometres and the July, 2012, median was 4.6 million square kilometers, the Arctic consortium reports in its most recent Sea Ice Outlook.
Those numbers compare with an average low from 1979 to 2000 of 6.7 million square kilometres.
A study in the journal Nature reveals the environmental cost of releasing methane as Arctic sea ice melts could hit the trillions of dollars.
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