The solar forecast calls for sluggish times ahead, according to scientists in Boulder, Colo.—which could have a cooling effect on Earth. A better understanding of solar processes and their climatic impacts will be key to understanding how far such quiescence could go to counteract global warming caused by pollution from fossil fuels.
There's little doubt the sun's been in a funkever since solar cycle 23 wound down in 2007. (Astronomers began to number the solar activity cycles in 1755.) The ramp-up to the peak of the next cycle is taking longer than expected and has been feeble, with precious few sunspots.
Normally, at the apex of each 11-year solar cycle—for cycle 24 it should occur around 2013—the sun's surface becomes especially frenetic, erupting into a climax of sunspots and flares. The outbursts can bombard the planets with gusts of highly charged solar wind, which triggers effects on Earth ranging from spectacular aurorae to interference with communications networks and even—in the worst cases—disruptive surges in power grids.
As the sun pushes toward the height of cycle 24, we'll still see a rise in solar activity, predicts Tom Woods, a solar physicist at the University of Colorado at Boulder'sLaboratory for Atmospheric and Space Physics (LASP), but "I think you can say with pretty fair confidence we're going to have a low maximum."
Predictions of global cooling became popular among climate change contrarians during the unexpected pause between solar cycles 23 and 24 and haven't completely subsided. But the degree to which a quiet sun could chill Earth, especially in the face of pollution that's warming the planet, is uncertain. Solar researchers are increasingly eager to quantify the sun's role, given the global importance of the question.
There's little doubt the sun's been in a funkever since solar cycle 23 wound down in 2007. (Astronomers began to number the solar activity cycles in 1755.) The ramp-up to the peak of the next cycle is taking longer than expected and has been feeble, with precious few sunspots.
Normally, at the apex of each 11-year solar cycle—for cycle 24 it should occur around 2013—the sun's surface becomes especially frenetic, erupting into a climax of sunspots and flares. The outbursts can bombard the planets with gusts of highly charged solar wind, which triggers effects on Earth ranging from spectacular aurorae to interference with communications networks and even—in the worst cases—disruptive surges in power grids.
As the sun pushes toward the height of cycle 24, we'll still see a rise in solar activity, predicts Tom Woods, a solar physicist at the University of Colorado at Boulder'sLaboratory for Atmospheric and Space Physics (LASP), but "I think you can say with pretty fair confidence we're going to have a low maximum."
Predictions of global cooling became popular among climate change contrarians during the unexpected pause between solar cycles 23 and 24 and haven't completely subsided. But the degree to which a quiet sun could chill Earth, especially in the face of pollution that's warming the planet, is uncertain. Solar researchers are increasingly eager to quantify the sun's role, given the global importance of the question.
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