As we're all preparing for record cold, it may be hard to conceive that the Arctic is melting as a result of climate change -- four times the global average. But that's what is sending a polar vortex further south. Via Scientific American:

Scientists have known for years that the Arctic is warming faster than the rest of the planet, a phenomenon known as “Arctic amplification.” But until recently, both scientific papers and news reports have typically reported that temperatures there are rising at about two to three times the global average rate.

A new study, just out yesterday in the journal Communications Earth & Environment, is the latest to weigh in. It finds that the Arctic Circle — the area located above 66.5 degrees latitude — has warmed by more than 5 degrees Fahrenheit since 1979.

In all, the study concludes, the Arctic has warmed at about four times the global average rate over the last 43 years.

“Of course everyone knows that … the Arctic warms faster than the rest of the globe,” said Alexey Karpechko, a scientist at the Finnish Meteorological Institute and a co-author of the new study. “But I think the number — nearly four times that we found now — is simply quite impressive.”