Hugh Pickens DOT Com writes: Robert Lee Hotz reports in the WSJ that solar activity is stranger than in a century or more, with the sun producing barely half the number of sunspots as expected and its magnetic poles oddly out of sync. Based on historical records, astronomers say the sun this fall ought to be nearing the explosive climax of its approximate 11-year cycle of activity—the so-called solar maximum. But this peak is "a total punk," says Jonathan Cirtain. "I would say it is the weakest in 200 years," adds David Hathaway, head of the solar physics group at NASA's Marshall Space Flight Center. Researchers are puzzled. They can't tell if the lull is temporary or the onset of a decades-long decline, which might ease global warming a bit by altering the sun's brightness or the wavelengths of its light. To complicate the riddle, the sun also is undergoing one of its oddest magnetic reversals on record with the sun's magnetic poles out of sync for the past year so the sun technically has two South Poles. Several solar scientists speculate that the sun may be returning to a more relaxed state after an era of unusually high activity that started in the 1940s (PDF). "More than half of solar physicists would say we are returning to a norm," says Mark Miesch. "We might be in for a longer state of suppressed activity." If so, the decline in magnetic activity could ease global warming, the scientists say. But such a subtle change in the sun—lowering its luminosity by about 0.1%—wouldn't be enough to outweigh the build-up of greenhouse gases and soot that most researchers consider the main cause of rising world temperatures over the past century or so. “Given our current understanding of how the sun varies and how climate responds, were the sun to enter a new Maunder Minimum, it would not mean a new Little Ice Age," says Judith Lean. "t would simply slow down the current warming by a modest amount."
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