Open Water Circling North Pole? Not Quite
By Andrew C. Revkin
There have been some breathless headlines in the last few days about the North Pole’s being an “island” for the first time in 125,000 years. Aside from the fact that 90 degrees north sits in the middle of a 2.5-mile-deep ocean, that’s quite a statement considering two things: first, no one has been routinely monitoring sea ice along both coastlines between then and now, and second, the region was clearly warmer than it is today (in summers) around 8,000 to 10,000 years ago — on both the Siberian and North American sides.
And one of the groups focusing most closely on possible Arctic shipping lanes, the National Ice Center operated by the Navy and Commerce Department, says flatly that the satellites are misreading conditions in many spots and that there is too much ice in a critical spot along the Russian coast (highlighted in the smaller image above) to allow anything but ice-hardened ships to get through. In an e-mail message Wednesday, Sean R. Helfrich, a scientist at the ice center, said that ponds of meltwater pooling on sea ice could fool certain satellite-borne instruments into interpreting ice as open water, “suggesting areas that have substantial ice cover as being sea-ice free.” The highlighted area is probably still impassible ice, including large amounts of thick old floes, he said. I sent the note to an array of sea-ice experts, and many, including Mark Serreze at the National Snow and Ice Data Center, concurred...
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