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June 17, 2011

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Sunspot drop won't cause global cooling

SUNSPOT cycles - those 11-year patterns when dark dots appear on the solar surface - may be delayed or even go into "hibernation" for a while, according to a US scientist.

But contrary to some media reports, this does not mean a new ice age is coming, Frank Hill of the National Solar Observatory said.

"We have not predicted a Little Ice Age," Hill said, speaking from an astronomical meeting in New Mexico. "We have predicted something going on with the sun."

The appearance of sunspots helps predict solar storms that can interfere with satellite communications and power grids.

Hill and other scientists cited a missing jet stream, fading spots and slower activity near the sun's poles as signs that our nearest star is heading into a rest period.

"This is highly unusual and unexpected," he said in a statement released on Tuesday. "But the fact that three completely different views of the sun point in the same direction is a powerful indicator that the sunspot cycle may be going into hibernation."

That hibernation would not begin now, as the current sunspot cycle, the 24th, has recently passed its minimum. Hill and his colleagues pondered a slowdown in sunspot activity in the 25th cycle, expected sometime around 2019. The scientists could not say if this cycle was related to a previous period known as the Little Ice Age.





 

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