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Marco Werman: I’m Marco Werman, this is The World. A strange thing happened here in Boston over the weekend: the temperature broke freezing. Crisis for people trying to remove mounds of snow, like me, it got a whole lot heavier. There’s tons of snow everywhere here but it’s the cold that’s really done us in, a stretch of frigid weather unlike pretty much anything anyone can remember. Emerging research suggests an entirely counterintuitive reason for this. One of the people doing that work is Jennifer Francis. She’s an atmospheric scientist at Rutgers University. Professor Francis, you found that we’re having a wicked cold winter here in Boston, as Bostonians would say, because the Arctic is warming up? Can you tell us how that works?
Jennifer Francis: I have to start out by saying that we can’t draw a straight line between what’s happening in the Arctic and what’s happening to us in the east here this year. What we do think is happening is the Arctic warming so fast is making it more likely that these kinds of patterns will happen more often. The idea is that the difference in temperature between the Arctic and down south here is the main fuel behind the jet stream; the jet stream creates our weather. When that Arctic is warming so fast, that means there’s less fuel driving the jet stream. When the jet stream has less fuel, it flows more slowly and it tends to take these big north/south dips as it travels around the northern hemisphere. So, this winter we happened to be in one of those big dips, and when we’re in one of those big dips, that’s when we get our cold winters.
Werman: These kinds of weather patterns that you’re talking about, you mean these nor’easters that we’ve been getting hit with in New England every four days or so?
Francis: Well, it’s actually bigger than that. You have to step back and look at what the jet stream is doing all around the northern hemisphere. What we see is this very wavy pattern in the jet stream; so, there’s a huge northward swing over the west that’s causing California’s drought and the heat wave they’ve been having there and, at the same time, it takes a big dip southward over the east. That allows the Arctic air to plunge far south and we happen to be in the stormy part of the jet stream. If you go to Europe, last winter and this winter the UK has had extremely strong storms that have been very persistent--you can think back to the Olympics last winter and how much trouble they were having keeping snow on the ski slopes, and you can go all the way around to Alaska and they’ve been having two very warm winters in a row. The climate system is a very complicated thing and there are a lot of other things that are happening at the same time, but everything is connected and it all goes back to what the jet stream is doing.
Werman: Some people here in Boston are saying this cold and snow is unprecedented so it’s probably not going to happen again. Based on what you’re seeing, is that a safe assumption?
Francis: It’s not a safe assumption at all and there are other factors that are coming into play as well. In addition to the ones that I’ve been talking about, we know that the ocean temperatures off of our coast here have been warming, creating more evaporation, puts more moisture in the air. That moisture is also fuel for storms.
Werman: I know you’re with Rutgers but you’re just about an hour or so down south from us here in Boston. It’s usually warmer there than here; I know you guys have been hammered also this winter though. How has it been for you there?
Francis: Well, as a meteorologist it’s been very exciting, but I know it’s caused a lot of pain and a lot of damage. It all goes back to where the jet stream is. If the jet stream is a little farther offshore, then we get a bunch of snow too. We’ll always have winter, winter is not going away.
Werman: Jennifer Francis, an atmospheric scientist at Rutgers University. Thank you.
Francis: You’re welcome. Any time.