The connection between a melting Arctic and frigid temperatures on the East Coast.
How cold is it? Cold enough to freeze an iguana in Palm Beach. Officials have warned residents of South Florida to look out for cold-stunned lizards falling from trees.
Meanwhile, 6,000 kilometers to the north, the Arctic has less sea ice than at any time in the 37 years that satellites have been measuring ice coverage. And while most of eastern North America is expected to be even colder by Friday, with temperatures set to plunge, Juneau, Alaska, will be a relatively balmy 6℃ (42℉).
What about climate change? The fact that it is cold today in Palm Springs and warm in Juneau is weather. Climate is long-term trends—years—of weather. And one of those trends is increased extreme weather, including winters too warm to ski and winters too cold to go outside.
Every winter, an extremely cold pool of air forms over the Arctic and is normally trapped in the polar vortex, a gigantic circular weather pattern around the North Pole. But the vortex is weakening, allowing the Arctic air pool to escape south when conditions are right. Researchers now believe it is the combination of a warmer Arctic and the loss of sea ice, along with a strong west-coast ridge of high pressure, that allows the polar vortex jailbreak.
Climate change is heating up the Arctic far faster than anywhere else in the world. The ice covering the Arctic Ocean has shrunk rapidly—50 percent of the summer ice extent disappeared in just the last 20 years. Without its ice cover, the Arctic Ocean is warming, especially under 24 hours of sunlight in summer. Warmer water means there is less ice even in winter, when there is 24 hours of darkness.
While it was record-breakingly cold on New Year’s Eve in parts of eastern North America, the Arctic Ocean broke a different record, with a whopping 1.35 million square kilometers less sea ice—an area the size of Texas, California, and Minnesota combined—than the 1981 to 2010 median.