The northern lights have been particularly spectacular in 2013 as the sun is expected to reach the peak of its 11-year solar cycle later this year.

CNN: Northern lights dazzle Northern Hemisphere

The sun is currently in an active phase of its 11-year solar cycle, and it should continue to fire off big storms for a while yet.

MSN: Amazing video captures magical-looking sun storm

The data, from NASA's TIMED mission, show that Earth's thermosphere (the layer above 62 miles or 100 km above the Earth's surface) "responds quite dramatically to the effects of the 11-year solar cycle, " Stan Solomon of the National Center for Atmospheric Research in Boulder, Colo.

MSN: Earth's upper atmosphere cooling dramatically

Dan Hershman's life changed dramatically after he photographed a spectacular aurora in Washington state in 2000, which was a peak year in the solar cycle.

CNN: 'Dancing lights' draw thousands to frozen north

The sun is in an active phase of its current 11-year weather cycle, which scientists call Solar Cycle 24.

MSN: Big sunspot unleashes an intense solar flare

Warren White of the Scripps Institution of Oceanography in La Jolla, California, and his colleagues were the first to find that sea-surface temperatures across the globe swing up and down in a 10-to 12-year period that lags behind the solar cycle by two to three years.

ECONOMIST: The earth��s climate

Solar activity fluctuates over an approximate 11-year cycle.

BBC: System could warn of solar storms

Solar experts believe that the tachocline may be the source of powerful magnetic fields that produce strong solar flares and solar winds, and create sunspots that mysteriously appear and disappear during an 11-year cycle.

BBC: Sun has strange 'spin cycle'

In terms of natural sources, solar storms strong enough to create a devastating EMP peak in 11-year cycles coincidentally the cycle is expected to peak again in 2013.

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