How a vicious cycle brings us warm air in Alaska and cold deep enough to kill off our ash borers.
Casey Bright during one of the coldest days in 20 years in Minneapolis, Jan. 6, 2013. As a precaution against the record low temperatures, the governor of Minnesota shut public schools statewide Monday, for the first time in 17 years. (Jenn Ackerman/The New York Times) ORG XMIT: MIN2014010911403327
In the 19th century, the word frontier evoked a perilous wilderness. In the 20th it meant outer space. I think this one, the 21st, will be remembered (if we manage to be remembered) as the time humanity set out into an altogether different type of uncharted territory — a place so strange and unpredictable that even its name changed from one decade to the next, all the better to capture its constant state of flux.
At the moment this new frontier is known as climate change, the term global warming having been ditched when it became clear that the effect of too much CO2 in the atmosphere was a bit more complicated than that label implied.
When I first got interested in the phenomenon in the 1980s, scientists called it the greenhouse effect. The consensus was that global warming would be more broadly understood. The Earth is heating up, stupid.
Except that lately our part of the world has been fairly dramatically cooling down.
Climate change leaves nature’s options open. Seems we’re in for just about anything, weather-wise, as long as it’s extreme. I’m talking drought, famine and wildfires one year, epic floods the next.
The polar vortex is a fascinating concept. In a nutshell, it’s what happens when hot and cold air collide, and the jet streams — which usually circle the globe in a fairly direct path from west to east — get all funky and weird. If these recent jet streams were people, you’d have to assume they were drunk.
Why a torrent of frigid air suddenly swooshes down from where it belongs and starts freezing people’s plumbing in Atlanta is because …
Imagine a rubber band that’s been stretched to the point where here and there it’s starting to fray. You’ve got some weakness in the band. It’s kind of like when you have an artery blow.
I’m gonna start over, OK?
The polar vortex is what happens when the Arctic air is a lot warmer than normal compared with the tropical air. It’s because of polar ice melting. (This is in the Arctic Ocean, where you see polar bears stranded on sheets of floating ice.) Which creates worse volatility than if this were happening in Antarctica, even though the South Pole is colder. They don’t have a lot of water down there. Antarctica is a continent.
I think it would be safe to describe this polar vortex as triggered by a vicious cycle. The CO2 in the atmosphere captures heat. Imagine a thick wool blanket. The melting ice radiates heat into the air, warming it up even more, whereas solid ice has the opposite effect. It stores cold.
Now it’s suddenly 38 degrees Fahrenheit in Alaska, and that warm air literally shoves the cold air down toward Chicago, because where else can it go? And remember that rubber band? The jet stream starts to buckle and you get that huge swoosh. Kind of like Nike’s logo times a thousand — no, a million.
Another way you can think of it is figure skating. I got this from the Internet, so don’t hold me to it. When figure skaters spin, it’s like the polar vortex in that the faster they spin, the better aligned they are. But when they start to put the brakes on, sometimes a knee will pop out or even a whole arm. That arm is like the polar vortex. When you look at the pictures, you can see that the vortex does look kind of like a rounded elbow.
Going back to my point, climate change is the new frontier. I think of it as a crazy adventure. Noxious weeds are moving our way, along with some fairly disgusting insects. It’s how we got emerald ash borers — only now we’re betting on the polar vortex to kill them off and quite possibly save the forests. The larvae can’t survive minus-30 temperatures.
Other bugs work differently. Japanese beetles’ larvae — larvae is the scientific word for eggs that hatch grubs (i.e., gross white worms) that in this case turn into the winged beetles that simultaneously shred and copulate on your roses — overwinter in the ground (not in trees), where it never gets much below freezing.
The best way to kill off Japanese beetles (if you’re a religious person) is to pray for drought. Without moisture, according to University of Minnesota entomologist Jeff Hahn, they’ll desiccate.
Sorry, but you’re gonna have to look that one up.
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