In yet another sign of climate change’s decimating effects on Arctic sea ice, the National Oceanic and Atmospheric Administration (NOAA) just kicked off a program to update some of its nautical charts.
As Climate Central reports, routes through the Arctic Ocean have great economic value. They can serve as a shortcut between Europe and Asia, which can save shipping companies many thousands of miles of travel and thus considerable costs. But these passages have generally been blocked by ice, making extensive mapping of the sea floor to guide ships unnecessary.
Now that situation is changing. In 2012, the “minimum extent” for Arctic sea ice — the low point in the cyclical shifts the ice coverage goes through annually — reached a measure lower than any that’s been recorded since scientists began collecting satellite data in the late 1970s. At 3.41 million square kilometers, 2012′s minimum beat out the previous record, set in 2007, of 4.17 million square kilometers. For reference, that drop of roughly 800,000 square kilometers — an 18 percent collapse — constitutes an area larger than the state of Texas.
And with all that melting, the arctic routes are opening up, requiring NOAA to lay down 14 new charts in order to keep commercial traffic along the new paths as safe as possible:
The revisions affect Alaska’s coast, which has America’s only Arctic seafront. As a result of global warming, ice that has historically blocked Arctic waters, even in summer, has been plummeting in recent years, with 2012 ice melting back to the smallest extent since satellite records began. And as sea ice recedes, said NOAA Coast Survey director Rear Admiral Gerd Glang in a press release, “vessel traffic is on the rise.” [...]
Already by 2010, both the Northwest Passage across the Arctic coast of Canada and the Northern Sea Route, across Russia, had been ice-free simultaneously for an unprecedented third year in a row, encouraging a flurry of interest by commercial ship companies. Last summer a Chinese ship navigated the even more reliably frozen route right across the North Pole. [...]
“We don’t have decades to get it done,” said Capt. Doug Baird, chief of the Coast Survey’s marine chart division, in the press release describing the agency’s new Arctic Nautical Charting Plan. “Ice diminishment is here now.”
In fact, the collapse in the coverage area of Arctic sea is a radical shift unprecedented in at least 2000 years, as far as scientists are able to determine. It’s been matched by an equally dramatic drop in the volume of ice — a plunge to one fifth its level in 1980 — that was recently confirmed by the work of Britain’s Natural Environment Research Council (NERC) using the European Space Agency’s CryoSat-2 satellite. At this point, most experts think a completely ice-free Arctic could be a reality as soon as 2030.
Due to feedback loops, global warming actually affects the Arctic faster than other areas. Sea water absorbs much more of the sun’s heat than the relatively reflective ice cover — so as the ice recedes and exposes more of the ocean to sunlight, the ocean temperature rises. That in turn warms the local air, which makes the formation of new, thicker, lasting ice even more unlikely, and the process circles around again.
All this can in turn effect the wider planet: Warmer and and moister air in the Arctic atmosphere can alter the climate patterns that keep frigid air circling northward, along it to plunge south — a possible factor in the extreme winters the Northern Hemisphere has been seeing recently. It can also speed up the melting of glaciers and ice caps in Greenland or the Canadian Archipelago, and even speed up the melting of northern permafrost. That latter result threatens to damage homes, roads and other infrastructure that rests on soil which typically remains frozen. And melting permafrost also promises to release many gigatons of methan, an even more potent — though shorter-lived –greenhouse gas than carbon dioxide.