 By PETER PORCO Anchorage Daily News December 29, 2005
No joke. Scientists at a recent convention in San Francisco warned that the aurora may move to Siberia over the next 50 years because Earth's magnetic north pole is drifting that way. And doing it mighty fast, as these things go. Sayonara, aurora. But don't blame this on global warming. The cause lies in the Earth's molten core of nickel and iron, which acts like a giant bar magnet, said Neal Brown, director of the Alaska Space Grant Program at the University of Alaska Fairbanks and a retired geophysics professor.
The magnet lines up roughly north-south and produces Earth's protective magnetic field as well as the polarity that helps birds, fish and compass-bearing humans navigate the globe. The north magnetic pole also determines where the northern lights will shine. If the pole is drifting - and scientists say the magnetic pole drifts all the time - the lights must drift along. The dazzling, dreamy northern lights inspire photographers to wait through a cold night for a prize shot and poets to write of the luminous soul of the North. To think of Alaska without the aurora borealis is, well, unthinkable. "That's amazing. That's amazing," said Jim Varsos. He is better known as Hobo Jim, balladeer and troubadour of Alaska stories and legends. "I couldn't imagine wintertime in Alaska without the northern lights," he said. "That would be to me a seriously endangered species." If solace must be found in such news, here it is: Although a split-second geologically, 50 years is a long time in human terms, and people would hardly notice the change, said Jack Townshend of Fairbanks, Alaska, the special projects coordinator for the U.S. Geological Survey's geomagnetism group. "You'd start seeing a little less, and the average citizen won't know it," Townshend said. "The biggest effect could be on the tourist industry." There's actually no certainty either way - that the drift will continue toward Siberia, or reverse itself, or even move into a new direction altogether, said Jeffrey Love, leader of the USGS geomagnetism group. Love, who's based in Denver, spoke by phone from San Francisco where he was attending the recent meeting of the American Geophysical Union. It was at the meeting on Dec. 8 that, The Associated Press reported, Oregon State University scientist Joseph Stoner forecast the pole leaving North America for Siberia and Europe. Love said the claim by Stoner could not be positively evaluated. "I personally would not want to predict what it's going to do in 50 years," he said. "(Yet) if it continues to drift north, it's also true that the auroral zone will drift north with it." Alaskans might still see the lights in that case, but perhaps as people in the Lower 48 see them today - only when severe solar storms spread the auroral zone far and wide. The north magnetic pole is not the same as "true north," which is the geographic pole that caps Earth's rotational axis. Nor is the magnetic pole a point on the surface. Rather, it's a broad field up to 200 miles across, according to Brown, of the Alaska Space Grant Program. The pole at present is at 82.7 degrees north latitude in the vicinity of the northern end of Ellesmere Island in the Canadian Far North, or 7.3 degrees south of true north. It is moving north at the rate of nearly half a degree and west by one full degree every year, Love said. "If it continued (drifting) at the current rate, in approximately 20 years, we'd have the magnetic pole approximately aligned with the geographic pole," he added. The magnetic pole had been drifting more or less south of true north for hundreds of years but was found about five years ago to have switched course and picked up speed, Brown said. "Clearly," he said, "the magnetic pole stopped its 400-year (south) movement, but is now rapidly . . . moving (north)." Scientists do not understand why the pace of drift has quickened, Brown said. But whether they know or not, the idea of losing the aurora made the 53-year-old Hobo Jim wince, and make a plan. "If this takes 50 years, I guess what I'll have to start doing is benefits to save the northern lights," he said. "I've got about 40 years to get ready."
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