With the launch of a Polar Vortex Twitter account, videos of boiling water freezing going viral, and the Weather Channel reporting on the "shattering" of cold records, anyone tracking the recent cold snap across the eastern and middle parts of the United States could be forgiven for thinking this sort of cold was unprecedented.
In fact, it's not.
"This is not anything that I would deem to be unusual or extraordinary," said Mark Wysocki, the New York state climatologist.
"The type of winter that we are currently experiencing we have experienced in the past, when you take a look at records across the Midwest and Northeast," he continued.
William Schmitz, the service climatologist and a meteorologist at the Southeast Regional Climate Center, agreed.
"It's cold," Schmitz said. "But just like the Northeast, it wasn't all-time record-breaking."
While cold records may be set for individual days -- Monday in Chicago, for example, was the coldest Jan. 6 yet observed, with a low of minus 16 degrees Fahrenheit -- temperatures are not reaching record winter lows and in many cases are far from it.
In Chicago, on Jan. 16, 2009, the town reached minus 18 F, part of another winter cold snap. On Jan. 20 of 1985, the city saw a low of minus 27 F.
In the Twin Cities, the record winter low is minus 32 F. The cities reached minus 22 F, a full 10 degrees above the record, in this cold event, said Pete Boulay, a climatologist at the Minnesota State Climatology Office.
Scott Unger, a National Weather Service meteorologist in Nashville, Tenn., said the last time that city got down to the single digits was 2009.
It's 'been quite a while'
"Arctic blasts like this are not completely uncommon, but it has been quite a while since this happened here," said Unger. "Last night we came in at a 2, and our yesterday's high was 20."
Atlanta and other Southeastern cities saw similarly chilly temperatures, with the expected high for yesterday reaching 24 F.
But a cold snap the city experienced in February 1996 was worse, with daily highs reaching only 18 degrees, said National Weather Service meteorologist Ryan Willis.
In the 1980s, Willis said, cold periods like this were much more usual. In the recent past, they have become less frequent. This is perhaps why the cold seems out of the ordinary.
New York climatologist Wysocki said that since the last couple of winters have been fairly mild, this one, which he called "typical," might seem worse in contrast.
"I'm sure if people sat down and really thought about it, they'd think, 'I've experienced this weather before, and this is nothing new. It's just been a while since I've had it, that's all,'" he said.
One of the reasons this winter has such fluctuations between hot and cold, without a clear signal dominating, is that there is not an El Niño or La Niña in the Pacific Ocean. Such climate phenomena will often set the tone for a winter, pushing a certain pattern, like snow or cold temperatures, to dominate in different parts of North America, said Wysocki.
"We don't have a strong [Pacific Ocean] signal, which means all bets are off for this winter. It's just going to be an average winter," he said.
As for the dreaded "polar vortex," which is responsible for the cold sweeping through much of the country? It's there every winter but moves around -- sometimes it's nearer Canada and the United States, other times closer to Asia and Europe, Wysocki said.
'Polar vortex,' an old acquaintance
In this case, a portion of the vortex spilled down in the United States, bringing cold air and winds with it.
"It's a fancy word for saying an intense low pressure that is spinning around up in the Arctic. And we like to call it a vortex, because it spins. But it makes it sound evil," Wysocki said, laughing.
Even though the cold temperatures are not record-breaking, they are still very cold, and wind chills across the region have been bitter, leading to wind chill advisories in many areas.
Schools were closed across much of the area affected by the cold snap, including in the Twin Cities on Monday, and there were closures and delays yesterday in much of the Southeast as the weather moved south.
As is typical when cold weather strikes, climate skeptics, including Donald Trump, pounced on the weather as proof that global warming is not happening.
Groups such as the Union of Concerned Scientists responded with fact sheets explaining the difference between climate and weather.
A number of media outlets tried to link this recent cold outbreak with a wavier jet stream that is possibly caused by the reduction in temperature difference between a much warmer Arctic, which is heating up rapidly due to global warming, and the lower parts of the world.
However, the science behind the link between warming in the Arctic and wackier weather in the midlatitude regions like the United States, Europe and much of Asia is far from proven.
Weather weirding? Wait till summer
Research so far has shown that if there is any connection at all, it is likely to be a small one (ClimateWire, Sept. 4, 2013).
Martin Hoerling, a scientist at the National Oceanic and Atmospheric Administration's Earth System Research Laboratory who researches the connections between climate change and weather extremes, said a link between a warmer Arctic and the recent cold is unlikely.
"If there were a link, it would be more likely to occur in fall [when the Arctic sea ice is at a low and the region is warm] than it would in January [when the Arctic is ice-covered and cold], so from that point of view, it's not a compelling candidate at this time of year," Hoerling said.
Hoerling also addressed the idea of weather weirding, that climate change is causing the weather to behave more erratically. Scientists analyzing temperature fluctuations in the United States have been unable to find any increase in temperature variability, he said.
"The weather is not getting weirder in our neck of the woods, as best as we can tell," he said. One area where a climate change signal is apparent, said Hoerling, is in extreme high temperatures.
"If you take the whole U.S., the indications are that there is an increasing frequency of record high temperatures versus record daily low temperatures," he said. In 2011, the Intergovernmental Panel on Climate Change released a report on weather extremes and climate change (ClimateWire, Nov. 18, 2011).
In that report, researchers reported high confidence in exactly what Hoerling said the data showed -- an increase in extreme temperatures.
And as University of Washington meteorologist Cliff Mass pointed out in a recent blog post about the cold snap, data from NOAA's National Climatic Data Center do not suggest that cold waves are increasing.
The title of the post is perhaps the best summary of the science to date on the link between global warming and cold snaps. It reads: "Does the Cold Wave Imply Anything About Global Warming? The Answer is Clearly No."
Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500