It's become as much a winter tradition as eggnog at Christmas and champagne on New Year's Eve — the first major snowstorm of the year bringing out the climate-change skeptics. And the bona fide blizzard that has frozen much of the Northeast just a few days after winter officially began definitely qualifies as major. But while piles of snow blocking your driveway hardly conjure images of a dangerously warming world, it doesn't mean that climate change is a myth.
One theory is that a warmer Arctic may actually lead to colder and snowier winters in the northern mid-latitudes. Even as countries like Britain — suffering through the coldest December on record — deal with low temperatures and unusual snow, the Arctic has kept on warming, with Greenland and Arctic Canada experiencing the hottest year on record. Temperatures in that region have been 5.4°F to 7.2°F (3°C to 4°C) above normal in 2010. As a result, the Arctic sea-ice cover has continued to shrink; this September, the minimum summer sea-ice extent was more than 770,000 sq. mi. (2 million sq km) below the long-term average, and the third-smallest on record. Snow may be piling up in midtown Manhattan, but the Arctic is continuing its long-term meltdown.
"One theory" - what do we mean by theory? From Wikipedia:
The word theory, when used by scientists, refers to an explanation of reality that has been thoroughly tested so that most scientists agree on it. It can be changed if new information is found. Theory is different from a working hypothesis, which is a theory that hasn't been fully tested; that is, a hypothesis is an unproven theory.
The word theory also distinguishes ideas from practice. The words empirical and clinical are also used to distinguish theory from practice.
Yes, we have a second" reality that has been thoroughly tested" to explain the phenomenon.