Posts Tagged ‘Sun’

The Sun is Acting Strangely

November 14, 2013
History of sunspot number observations showing...

History of sunspot number observations showing the recent elevated activity. (Photo credit: Wikipedia)

 

 

Glenn Reynolds linked to this story at Slashdot.com about the puzzling behavior of the Sun. I wrote something about the worrisome lack of solar activity since the last cycle almost two years ago and it does not look as if things are getting any better. The Sun ought to be approaching the maximum point of its eleven year cycle but so far this maximum has not amounted to vary much.

 

“Robert Lee Hotz reports in the WSJ that current solar activity is stranger than it has been in a century or more. The sun is producing barely half the number of sunspots as expected, and its magnetic poles are 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. ‘It would simply slow down the current warming by a modest amount.'”

 

I’m worried. We could be in for another Little Ice Age, which really wouldn’t be much fun at all. Wouldn’t be ironic, though, if all the carbon dioxide we are emitting was the only thing keeping the glaciers from moving south again? I think I read a science fiction book about that once.

 

 

 

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More on the Solar Storm

September 29, 2011

There are some pictures of the active region at discovermagazine.com as well as some information here and here.

I hope they don’t mind if I use this picture, but I thought it was interesting.

See how small the Earth is compared to a sunspot.

Here is a picture of the whole region.

And a warning.

That region is pretty feisty, and the odds of us getting more flares from those spots are pretty good. The Sun’s rotation is currently taking them toward the center of the disk, where a good sized explosion is then directed toward us, and particle waves from the blast can then interact more efficiently with our magnetic field. We may be getting aurorae from them, and if things go well that’s all we’ll get! A big blast can damage satellites, and even put astronauts on the ISS at risk. We on the ground are pretty safe, since the Earth’s air absorbs the radiation — that’s why we have to launch satellites like SDO into space, so they can detect that energy in the first place!

However, a big blast can shake the Earth’s magnetic field, inducing a current in the ground that can actually overload power lines. We can get blackouts from such things, and it’s happened before. This is a real problem that can do millions or even billions of dollars of infrastructure damage (including money in the economy lost during the blackout). I know a lot of solar physicists are concerned about this eventuality, and are trying to get both the power companies and the government to take it seriously. I hope they do. We’re still approaching the peak of the solar cycle sometime in mid-2013 or so, and flares like the one Saturday will most likely be more common.

Although, I am actually glad the Sun is getting more active. There were practically no sunspots during the period known as the Maunder Minimum, from 1645-1715, which coincided with the Little Ice Age. This last solar cycle, the Sun seemed to be a little too quiet and there was some speculation that we might be entering into another minimum.

Here is a chart of sunspot activity over the last few centuries. It is probably a better indicator of global climate changes than human carbon emissions, but don’t tell Al Gore that.

 


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