The term had been around for a while. First described in the middle of the 19th century, it was named by scientists who were studying the upper atmosphere around the North and South poles in 1952.
But most of us, at least in the Eastern one-third of the United States, never heard it used until four winters ago, when a six-week-long outbreak of polar temperatures was accompanied by record winter snowfall in many locations.
That was when “cold wave,” the phrase most of used to describe arctic cold when it extended more than three or four days, gave way to “polar vortex.” (Briefer outbreaks were simply “cold snaps”).
And the term, largely absent from your TV meteorologist’s vocabulary during the winters of 2016-18, is back in use this winter as temperatures in the northern Midwest and northern Plains states reached all-time low temperatures of -20 to -40 decrees Fahrenheit.
So what is a polar vortex? It’s a large and persistent low-pressure cyclone that rotates counter-clockwise at the North Pole and clockwise at the South Pole, trapping cold air beneath and concentrating it in arctic regions. Occasionally, the vortex will weaken and split, spinning off a piece of itself south from the pole. The result is that the air in northern Minnesota is every bit as cold or colder than locations within the Arctic Circle.
Words and phrases come and go. Some likely disappear forever, such as the cowboys’ description in the late 1800s of a courageous person as someone with “more guts than you could hang on a fence.” Or the term “oojah,” which is what people said more than a century ago when they couldn’t remember the name of something.
Wonder why they didn’t just say “whatchamacallit” like the rest of us since at least 1921?
— BOB UNGER