This is Science Friday. I'm Ira Flato. Coming up later in the hour, we'll be unpacking the myths of spoiled food. How long can mayonnaise stay out before it goes bad? What do those dates on meat packaging really mean? And we'll be answering your question. So give us a call. 844-724-8255. What would you like to talk about?

You make the call, but you have to make the call.

844-724-8255.

But first, if it feels like you've been hearing about an unusual number of tornadoes recently, you are not wrong.

There have been reports of at least 1, thousand tornadoes in the U.S.

this year, 200 just in the past two weeks. The unusually high number has to do with the current

shape of the jet stream, and yes, there is a link to climate change. Here to tell us more about

that story, as well as other short subjects in science, is Sarah Zang,

staff writer at the Atlantic. Sarah, welcome to Science Friday. Hi, great to be here. So what's

this extreme tornado season? There was a tornado warning here in New Jersey, I mean New York,

just this past week. What's going on? Yeah, I live in Washington, D.C., and we also had a couple

tornado warnings this past week. So the reason that we've been having these tornadoes has to do with this unusual pattern of the jet stream across the United States. So the jet stream is this river of air. It's really high up in the atmosphere. It's kind of far above our heads, and it usually blows west to east, and it circulates the globe. Sometimes its path can get a little bit curved, and in the past couple of weeks, it's just been kind of extremely curved. It's basically formed a U across the United States. And inside this U, you have this blob of cold air. It's kind of for California, the northwest, in the southwest, and that's been unusually cold for the past couple of weeks. And outside of this U of the jet stream, you have warm air coming in from the Gulf of Mexico, and the rest of the country is actually having a heat wave. And the basic recipe for a tornado is cold air meets hot air, and then you have the winds of this jet stream, and that's basically what you're seeing in the middle of the country. We're seeing all these hundreds of tornadoes all of a sudden. So why is the jet stream acting so weirdly? Out of place. Yeah, there are a couple of possible explanations. One is just kind of the normal oscillations in the Earth's weather. So there's something called the Mad and Oscillation. And it's kind of like El Nino,

except it plays out in like the span of a few weeks rather than years. And basically what it means

is it's created this batch of thunderstorms over the Indian Ocean. And this has actually

ripple effects that has affected the path of the jet stream over North America. So like everything

is connected. And the other, of course, is, course, is what is the role of climate change, right?

So it's been also really warm in Alaska this year.

And there's this bubble of warm air that

maybe have pushed the cold air that is in the U

of the jet stream down.

And as the Arctic gets warmer, it's possibly

you might be seeing more of that. Obviously, it's always really hard to say, like, this particular event happened because of climate change. But as things happen in the future, we'll see, might see more of that coal there coming down, and then we can see how it's going to affect tornadoes in the future. Yeah, well, just the new normal. Next up, there was an amazing picture of a fossil I saw this week. It was like

...