They can survive being completely desiccated in long Arctic winters, returning to growth in warmer times, but Dr La Farge was surprised by an emergence of bryophytes that had been buried under ice for so long.

BBC: Centuries-old frozen plants revived

"All of the computer weather models agree that most of the U.S. will be warmer than usual, but at least we can see the end coming for La Nina, " said Ants Leetmaa, director of NOAA's Climate Prediction Center.

CNN: La Nina spawns extreme weather

First, the Pacific is going through a cooler period, called La Nina (with this one being particularly strong), and the Atlantic is going through a warmer period.

FORBES: 2011 Forecast: World Outperforms U.S., Europe Scuttles