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Climatologists’ new normal for winter: Fewer light snows, more big dumps

Climate scientists expect that as global warming progresses, our winters will see snowfall patterns move toward the extremes of long, dry spells and really big storms.

Climate scientists expect that as global warming progresses, our winters will see snowfall patterns move toward the extremes of long, dry spells and really big storms.
Courtesy of MnDOT

I shouldn’t assume that my preferences in winter weather are universal, but after three decades of living between Richfield and New Richmond, Wis., I feel confident saying that most of us along this part of the 45th parallel prefer a pattern of steady, moderate snowfalls to massive dumps and blizzards.

Many might even prefer that pattern to the kind of low-snow winter that curbs our skiing/snowmobiling/snowshoeing and leaves a ratty brown landscape from Thanksgiving to April Fools’ Day.

If you’re with me on this, I have some bad news: Climate scientists expect that as global warming progresses, our winters will see snowfall patterns move toward the extremes of long, dry spells and really big storms.

Quite a fine feature on this topic turned up on the AP wire yesterday, courtesy of science writer Seth Borenstein. Explaining that global warming is probably at work not only in the barren ski slopes so prevalent across the Midwest and Northeast in recent years, but also in the 2-footer that dropped on New England earlier this month, he writes:

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How can that be? It’s been a joke among skeptics, pointing to what seems to be a brazen contradiction. But the answer lies in atmospheric physics.

A warmer atmosphere can hold, and dump, more moisture, snow experts say. And two soon-to-be-published studies demonstrate how there can be more giant blizzards yet less snow overall each year. Projections are that that’s likely to continue with man-made global warming …

“Shorter snow season, less snow overall, but the occasional knockout punch,” Princeton University climate scientist Michael Oppenheimer said. “That’s the new world we live in.”

Ten climate scientists Borenstein queried agree with the general conclusions of the new research, though they had no personal stake in it.

And, really, the shift mirrors the changes we are seeing in warm-weather precipitation patterns, toward longer, deeper dry spells — even drought — punctuated by extreme rainstorms and flooding. The only difference in these two scenarios, really, is the temperature when the moisture starts to fall. That, and whether it soaks in and runs off — or has to be shoveled, snowthrown and plowed.

Over the past couple of years, climate scientists have begun to abandon the standard reluctance to attribute any single weather event to the world’s changing climate and to say, instead, that unusually intense drought, storms, wildfire seasons and other phenomena are what global warming looks like in real time.

And concern over here-and-now impacts was clearly a motivation, and message, for the tens of thousands of activists (including hundreds of Minnesotans) who gathered in Washington on Sunday in what organizers claim as the largest rally on climate issues to date.

However, nearly all of the examples in the public discussion thus far have been about warm-weather extremes. The new studies underscore that climate disruption is registering all year round.

A very close look at tornadoes

Speaking of extreme weather, I recommend IMAX movie “Tornado Alley,” which I viewed on Sunday at the Science Museum of Minnesota.

Because I happen to like watching big storms, on a screen and in real life, I’ve seen some impressive scenes over the years. But nothing this striking.

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“Tornado Alley” is really two movies, or two narratives woven into one.

The first documents the work of a 100-member research team using all manner of vehicles, instruments, scientific specialties, lucky charms and guts to gather tornado data from very close up, in quantities and at resolutions far surpassing what has been available.

Tornadoes are complicated, and so is the research. But the team’s focus is tight and two-fold: To solve the mystery of why some storms spawn monstrous twisters and nearly identical others do not, and to improve the system for issuing watches and warnings by breaking the code of incoming storm signatures.

Every guy should have one

The second story concerns Sean Casey, a sort of combat photographer on the front line of tornado tracking, who has built his own tank to carry himself, his cameras and a couple of helpers into the heart of huge tornadoes.

Yep, a tank, shielded with two-inch composite armor, windows of bulletproof glass, skirts than can be lowered to keep swirling wind from lifting it off the ground —and long, hydraulically extended spikes to nail the whole thing down in case the skirts and the vehicle’s 14-ton weight aren’t sufficient.

As far as I could tell, Casey’s ride sports “headlights” that don’t look all that street legal, a chassis and drive train that seem to need frequent roadside welding … and an ordinary-looking California license plate. Is this a great country or what?

(Much as I loved the film and love the museum, I must add that a similar film, though in non-IMAX format, can be watched online here. Also, that “Tornado Alley” curiously omits mention of research suggesting that this corridor, which stretches from Texas to Iowa and South Dakota and experiences 80 percent of the nation’s big tornadoes, is expanding as temperatures warm and atmospheric moisture loads increase.)

‘The Birds’ come to town

On the bright side, here’s a climate-related problem we’re not likely to experience anytime soon: A sky-blackening plague of roosting birds that people in the western Kentucky city of Hopkinsville are saying is like something out of Alfred Hitchcock.

As the zone where ground stays unfrozen through the winter expands northward, masses of certain migratory birds are abbreviating their southward journeys. According to a report from Reuters, lightly compressed:

Blackbirds and European starlings blacken the sky before roosting at dusk, turn the landscape white with bird poop, and the disease they carry can kill a dog and sicken humans.

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“I have seen them come in, and there are enough that if the sun is just right, they’ll cloud your vision of the sun,” said Hopkinsville-Christian County historian William Turner. “I estimate there are millions of them.”

David Chiles, president of the Little River Audubon Society, said the fact that migratory flocks are roosting in the city rather than flying further south is tied to climate warming. “They are ground feeders, feeding on leftover crops and insects. If the fields are frozen solid, they can’t feed.”

This year’s problems aren’t wholly unprecedented; Hopkinsville had a bad winter, birdwise, in the late 1970s.

This winter the city of 35,000 is trying to drive the invaders out with noise barrages from air cannons and small skyrockets, which unfortunately are also kind of hard on humnan residents and their pets.

And there are worries about histoplasmosis, a fungal lung infection transmitted in the bird droppings and persistent in soil for years.