Crunching the numbers: Will you see a white Christmas?
Crunching the numbers: Will you see a white Christmas?
There are two questions that arise at the end of every year. The first is: Did I fulfill all of my resolutions this year? And the answer to that is always no, unless you are lying to yourself. The second is: Will we have a white Christmas? And, pretty soon, that one’s going to always be no, as well. Unless you move to, say, Canada.
This year is one of the bubble years, a year in which a white Christmas is still possible. Yes, it’s warmer than usual — in fact, it’s the warmest year in American history — but the worst long-term effects of warming haven’t yet made December snowfall an improbability. So let’s ask the question.
Spoiler: For most of the country, the answer is always no. If you live in Miami, it likely never occurs to you to even ask it, unless the query comes up as you’re singing a Christmas carol. Angelenos, the same; snowfall is something to be visited on mountaintops, not seen in drifts around a palm tree.
For those for whom it’s possible, a secondary question: What constitutes a white Christmas? There are three options.
- Snow falling on Christmas
- Any amount of snow visible on the ground on Christmas
- A blanket of snow on the ground on Christmas
These are three very different things, requiring different conditions, appearing in decreasing order of likelihood. As a purist, I’ll insist that the third choice is what really constitutes a white Christmas, an amount of snow that deters going outside for long — an amount of snow that encourages the coziness of a warm house and a fire. Well, not a fire, given the carbon dioxide and particulate emissions. But you get my point.
The National Oceanic and Atmospheric Administration agrees with my vision of Christmas whiteness (so to speak). Here’s its map of the historic probability of an inch of snow on the holiday.
Click to embiggen.
I grew up in a bit of that dark purple stretch in western New York, hence my purism. If you find even a dusting of snow acceptable for your (lacking) standard, note that the odds of such snowfall are higher than the odds presented above. But also note that this is from data collected between 1981 and 2010, what I like to call “the old days.”
NOAA’s map doesn’t tell us anything about this year. So we turn to Weather.com’s white Christmas forecast.
Click to embiggen.
Weather.com, headquartered in Atlanta, uses the lowest standard for a white Christmas — any snowfall at all. And even under those conditions, it doesn’t look good for much of the country.
Being only a week out, we can get city-specific forecasts now. Such as for New York:
And Chicago:
And Denver:
Of those three, only Denver has a even shot at some snow, however little.
Incidentally, for those of you who took our comments at the beginning of this article to heart and had begun plans to move to our neighbor to the north, there’s no rush. Canada doesn’t look like it’s going to have a very white Christmas, either. From Smithsonian:
“We have this reputation. We are known as the Cold White North. But I don’t think we’re as cold and white as we once were,” said Environment Canada senior climatologist David Phillips to the [Canadian Press]. “Our reputation is being undermined. Winter is not … what it used to be. It was more of a done deal. It was more of a guarantee.”
During the 1960s, 70s, and 80s, says the CP, there was an 80% chance that it would be snowy on Christmas.
“Fast-forward to the last 20 years, and those odds on average have slipped to 65 per cent, according to Environment Canada.”
In short, then, there’s only one place on Earth where you can be guaranteed a white Christmas. No, not the Arctic circle (at least over the long term). Antarctica. That’s it. That’s your only option.
And if Antarctica stops offering a white Christmas, the holiday itself will probably have been abandoned in the transition to an ocean-based subsistence economy of nation-states constantly doing battle by outrigger canoe.
Merry Christmas, everyone!
Philip Bump writes about the news for Gristmill. He also uses Twitter a whole lot.
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