Winter Weirdness: Is Arctic Warming to Blame?

For Alaskans who have basked in record warmth, Atlantans who abandoned cars during a January snowstorm, or Californians enduring drought, this winter's extremes have been nothing if not memorable.

Drought or unusual warmth is in sync with the effects that climate scientists expect from global warming. But what about wintertime invasions of Arctic air into the US Deep South or into China, where, a new study indicates, record cold events became more frequent over the past 10 to 20 years?

For some climate scientists, January's extremes and the atmospheric patterns that nurtured and sustained them are fresh bits of information to apply to these intriguing questions:  Has global warming's effect on the Arctic set the stage for persistent weather patterns that lead to extremes?  If so, is the decline in Arctic sea ice the stage manager for the wintry events?

Winter Weirdness: Is Arctic Warming to Blame?