LINDA WERTHEIMER, HOST:
If you're listening to this program from the Midwest or East Coast, well, I hope you're nice and warm inside your house or car. President Trump took note of the frigid temperatures in the East this holiday season with this tweet - perhaps we could use a little bit of that good, old global warming.
Climate scientists note that while parts of the U.S. are much colder than average now, the world as a whole this week is warmer than the average over recent decades. One thing climate scientists have long been reluctant to say is that specific extreme weather events are the result of climate change. But NPR's Christopher Joyce says a little-noticed study this past year did prove a link.
CHRISTOPHER JOYCE, BYLINE: This was this - a study that determined that, yes, looking at events in 2016, 27 of them - they found three that were so off the charts that they had to be the result of what we have done to the planet. They're just beyond what is expected to be a natural event.
WERTHEIMER: What are they? What are the three events?
JOYCE: Well, one was the incredible heat that we experienced - the average temperature around the globe in 2016. It was 1.7 degrees Fahrenheit above the average in the 20th century. And that is just enormous. The second one - extreme heat waves in Asia, especially India and Pakistan. Hundreds of people died. The temperatures were just beyond belief. And the third one - one not noticed that much - but something called the blob, which was a section of water in the Bering Sea off the coast of Alaska that was just unusually warm - again, so warm that it's just beyond what could be modeled as being - as happening in a natural world.
WERTHEIMER: But still, how do they know that this was not just weird weather - certainly, extreme, unexpected, unusual?
JOYCE: You know, again, I have to use the word model, which people are afraid of. But they're computer models. And what you basically do is you recreate the world as it was before the Industrial Revolution and certainly before the mid-20th century when we started warming it up. And you put in all of the atmosphere. You put in the oceans, the circulation, the temperature. And you sort of create this world before we changed it. And then you create another model of the world we're in. And you take these events, and you put them in that model of what the world used to be like. And you can tell that they couldn't have been created by the forces that were at work before we warmed the planet.
WERTHEIMER: So those three things could not have happened absent global warming.
JOYCE: Yeah. I talked to one of the scientists who did the work - who compiled the work - Stephanie Herring of the National Oceanic and Atmospheric Administration. And this is how she put it.
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STEPHANIE HERRING: Not even one in a million. They cannot replicate them in a world without climate change is what the scientists are saying. It's a big result, yes. It's - again, you know, we've been doing this for six years, 131 papers. This is our first time seeing this.
WERTHEIMER: So this is a first?
JOYCE: They certainly have seen things like the coral bleaching in Australia of the Great Barrier Reef, for example, a terrible event not seen before in recorded history. But there's possibility that this could've happened in a non-warmed world. And so this is the first time they've been that certain.
WERTHEIMER: So do you think, now that scientists have connected these three awful events, that we'll hear more stories about this going forward?
JOYCE: Yes, I - indeed. I mean - and certainly, Stephanie Herring and others have told me the same thing. They think there are other events that were caused by climate change that they just didn't even get to because there are so many extreme events. They only looked at 27. I mean, look at Harvey, for example, this year. Harvey certainly was a huge hurricane. We've had huge hurricanes before. But what scientists are saying is it was so wet. So much rain fell. Texas has never seen that much rain over two or three days. And scientists say that's because of climate change. The Gulf of Mexico is so warm before that storm - that there's so much evaporation that that's what caused that incredible amount of rain. And their argument is that probably wouldn't have happened if it weren't for climate change.
WERTHEIMER: So what do we have to look forward to?
JOYCE: Well, you know, climate scientists will say we'll see more of things like Harvey because sea surface temperatures are going up. Storms are going to be wetter. Storms will probably be more intense. We'll see more heat waves unless we find a way to keep the planet from continuing to warm.
WERTHEIMER: NPR science correspondent Christopher Joyce, thank you.
JOYCE: Sorry to be so grim.
(LAUGHTER) Transcript provided by NPR, Copyright NPR.