Have you been outside lately? If you're anywhere on the East Coast of the United States, it was probably not a very pleasant experience. It snowed in Florida on Wednesday, and hospitals in Southern cities like Atlanta have seen a surge in hypothermia patients. Meanwhile, temperatures in North Dakota and northern Minnesota have been recorded in the negative 50s with windchill, which is dangerous enough to give someone frostbite within minutes. Oh, and sharks are literally freezing to death in the water.
Despite Donald Trump's tweets to the contrary, it's not insane to wonder if this fresh frigid hell has something to do with climate change. Some meteorologists have even taken to talk of a "bomb cyclone," which in the words of the always-measured and reassuring New York Post, is a sick joke by God designed to "make your life a frozen hell." But what the hell is a "bomb cyclone," and will it even be safe to go outside later on this week?
Rob Reale is a meteorologist who works as the director of education at the meterological firm WeatherWorks. He'd been working since 4 AM to draw up forecast reports for the company's clients when I got a hold of him Wednesday, but was kind enough to spend a few minutes with me on the phone explaining why it's so cold—and what's coming next.
VICE: The simple question I'm hearing most is the obvious one: Why is it so cold? I keep seeing news outlets refer a blast of Arctic air. Is this because the polar ice caps are melting, or is it more complicated than that?
Rob Reale: The answer is probably not, but it's tough to say for sure. It certainly has been anomalously cold. One thing that's typically present for the east coast to be cold is the jet stream to cause a large ridge out in the west that makes it warm and dry. We've seen that out in California—they're in desperate need of rain. What's happening is the warm ridge is out there, and what happens over us is a trough of colder air settles in. The pattern just happens to be so that the air flows directly out of Canada between them, and we've been getting cold shots.
The coldest New Year's Eve on record in New York City was 1 degree Fahrenheit—in 1917. If weather is getting more extreme due to climate change, why aren't we shattering temperature lows?
It's not unusual for there to be cold snaps, though I will say this is one of the most prolonged cold stretches we've had in recent memory. But I mean, it's common for brief arctic blasts to move through, and temperatures to go below normal. We just haven't had it [like this] in the past five to ten years. We're going on at least three weeks of prolonged cold air. But it's not necessarily colder than is ordinary. There haven't been too many record lows broken.
Why do I keep hearing about "bomb cyclones?" Who the hell came up with that term, anyway?
Is the word "bombogenesis" one that you've heard? That is a real weather term that has to do with rapid pressure falls below 24 millibars, which means that the [air] pressure is strengthening quite a bit. If it does that in less than 24 hours, it's considered a "bomb." This is a very strong storm that has to do with a lot of moisture being over the Gulf right now, and a disturbance that's kind of meeting up with that cold Arctic air. A lot of ingredients are there. Storms like this aren't completely out of the ordinary—we get maybe one per year. It's not a once-in-a-century storm.
"Bomb cyclone" is not a real word. I would imagine a newspaper heard "bombogenesis" and called it a "bomb cyclone." Kind of like how polar vortex became a thing. It's catchy.
What makes this different from a nor'easter, or is it just a really big one?
This is a nor'easter. [That's] just when there's a strong low-pressure over the northeast. Once the storm starts affecting the northeast, we'll call it a nor'easter. It's not a type of storm, it's a strong storm off the coast that's affecting a certain area.
So why is the pressure dropping so drastically? And how does a pressure drop cause winds to pick up?
It's a very complicated question. If you have higher pressure next to lower pressure, that alone is what causes the wind to strengthen. So if a meteorologist talks about a high-pressure day, that's associated with light winds and mild weather. But if you have a low-pressure day, especially near a high pressure, that gradient in that pressure is what causes winds to strengthen.
Most storms will form with a temperature gradient, which there is in the southeast [United States]. That's why storms form a lot of times off the mid-Atlantic and into the northeast—the Gulf current runs through there, and there's a temperature gradient in that area. Even if it's not a air temperature gradient, it's a water temperature gradient. Then there's moisture, and a disturbance moving through. This storm has those three basic ingredients right now.
In reading about this phenomenon, I've also seen the words "hurricane" "blizzard" and "cyclone." Is this like every extreme weather phenomenon rolled into one?
It's just a very strong coastal storm. It, in a way, has hurricane characteristics. The pressure is very low. One of the reasons the winds are so strong in a hurricane is because the pressure is so low that it creates a pressure gradient. As the storm strengthens, the gradient increases, and the wind will increase. There will be 40-50 mph winds up and down the coast. Not extreme winds, but very, very high winds.
I think people are mostly wondering how they are supposed to prepare for this weather in practical terms. Is it dangerous to, say, walk to work in this weather, or drive your car in your community, or should I put my wishful thinking about working from home to bed?
I wouldn't necessarily go out of your way to prepare for a Day After Tomorrow-type set-up, because this is something that almost everyone has lived through once, or twice, or multiple times. This isn't necessarily overly dangerous. Whenever the storm hits you, though, and there's 40-50 mph winds, no, you shouldn't be on the road. Are you gonna need to stock up for days and days? Probably not.
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