Scientists retire ‘implausible’ worst-case climate scenario

IRA FLATOW: This is Science Friday. I’m Ira Flatow. Last month, an international team of researchers walked back its worst case emissions scenario for climate change, which forecasts a whopping temperature rise of 4 degrees Celsius, 8 degrees Fahrenheit, by the end of the century. It seems like good news, right, that we’re not going in the wrong direction. But the revision came after years of criticism from climate scientists, and even led to President Trump weighing in on the change. Here to break down the course correction and controversy is senior environmental correspondent for Vox, Benji Jones, who’s also bringing us other updates in environmental news, including a special project of his own. Welcome back. Benji.

BENJI JONES: Hey, thanks for having me.

IRA FLATOW: Nice to have you. Let’s start off with what exactly this worst case scenario was, why was it proposed. Fill us in, please.

BENJI JONES: Yes. So the scenario was called RCP 8.5, and it essentially envisions a worst case scenario for rising greenhouse gas emissions, so basically, unabated emissions. So we’re talking about increases in coal use, increases in oil and gas, increases in combustion engines. And so under this scenario, we’re seeing not only a massive rise in emissions, but also a massive increase in warming, as you mentioned. And it’s sort of the most catastrophic view of climate change that has spawned a lot of scary headlines about what the future might look like. So the good news is that it doesn’t seem like we are on that path anymore. But there’s an important caveat, which is that we are still targeting pretty extreme climate change that’s going to have dire effects on the planet.

IRA FLATOW: And why were some scientists not on board with this?

BENJI JONES: Because– so when you think about climate modeling, you want to look at a range of different scenarios because there’s so much uncertainty. There’s uncertainty in terms of what policies different countries are going to implement. There’s uncertainty about the expense of technologies, clean energy technologies, which can help push us away from carbon-based fuels. So all of this uncertainty means that you want to actually model different scenarios of what might happen, especially when it means that we need to be preparing for different scenarios. It’s smart to prepare for the worst case scenario.

The reason that scientists decided to retire RCP 8.5 is because it was really based on what have become implausible scenarios in terms of the kinds of fuels that we’re using. So coal use is declining. Renewable energy is now overtaking coal use globally. We’re not seeing the worst case scenario for cars. There’s been a rise in electric vehicles, for example. And that RCP 8.5 envisioned a world in which we were even using coal-based fuels for cars. That is not on the table, really, anymore. And so the good news, again. And so really the change, the reason that they’re retiring RCP 8.5 is that we have seen actual climate progress across the world in terms of the use of renewables.

IRA FLATOW: Benji, how did President Trump get involved with this?

BENJI JONES: Yeah, so after this team of researchers published their updated emissions forecasts, Trump took to Truth Social and essentially used this revision, this retirement of RCP 8.5 to suggest that this alarm about climate change is totally overblown and untrue. Of course, Donald Trump has called climate change a hoax in the past.

And that’s the downside, too, of this news. It’s really hard to just see the nuance in this. We’re talking about a tapering off of the worst case scenario, but we’re still talking about a bad outcome if emissions continue on track as they are. So using this as evidence that we’re out of the woods, using this as evidence that climate science and climate alarmism is bad is not really accurate here.

BENJI JONES: All right. Let’s move on to some other stories, like new stats released on one of the deadliest animals to humans in the world, snakes. Why snakes?

BENJI JONES: Yeah so, I mean, it’s easy to think that the most dangerous animals are things like sharks or wolves or bears, these things that really have a lot of fear associated with them in pop culture. But in reality, one of the deadliest animals, as you mentioned, is snakes. They kill about 100,000 people a year, which is more than almost all other animals except for mosquitoes. And the reason for that is that we don’t have a great solution to snakebites.

So individual snakes require individual antivenoms to reverse the impacts, to avoid death. And they often require cold storage. And people who get bit by snakes are often in rural areas far from hospitals. And so the snake problem is pretty severe.

IRA FLATOW: And is it getting worse? I mean, what’s happening?

BENJI JONES: So I think what’s clear is that data on snake bites is getting better. So for example, India has started reporting much, much higher numbers of snake bites annually. And actually, of the 100,000 snake bite deaths in 2023, more than half of those occurred in India. So we’re seeing better reporting of snake-related deaths.

And the reason that India has seen such high number of snake deaths is because it has a large rural agricultural population. Farms attract rodents. Rodents attract snakes, and often these folks don’t have access to great health care. They might sleep on the ground, so they’re more exposed to snakes. So it really is specific to different places.

IRA FLATOW: Your next story takes us from snakes to birds. I know we are all too familiar with seagulls stealing our lunch at the beach, but I understand there’s new research about burglary between birds.

BENJI JONES: Oh, all right, I love this story. So there’s new research on a group of birds called honeycreepers in Hawaii. These are these iconic birds. They often have these curved bills used for getting nectar out of tube flowers. And researchers documented something called nest kleptoparasitism in three species of these birds. And what that means is that these birds are, instead of finding their own materials to build their nests, they’re stealing twigs and moss from other birds’ nests to build their nests. So yes, this is straight up rude bird burglary.

IRA FLATOW: And I would imagine this has got to be relatively common, right? It’s a good strategy if you don’t have to work so hard.

BENJI JONES: Yeah, so the researchers monitored a little over 200 honeycreeper nests and found 39 instances of theft. And yeah, from the one hand, it makes a lot of sense. It’s easier to just use existing materials than to find your own. But there are some potential trade-offs here. For example, there might be parasites associated with abandoned bird nests, so you might end up bringing parasites into your own nest. So there might be interesting benefits and costs here. But yeah, it’s funny to think about birds just being like, I’m not going to put in the work, I’m going to take yours. It’s very, very rude.

IRA FLATOW: Well, I would think if this is such a good strategy, it might be widespread with other birds. Do we know?

BENJI JONES: So we sort of do anecdotally. Over 40 species of songbirds have been reported to be stealing nest materials from one another. But this study that just came out in The American Naturalist was, to my knowledge, the first documented instance of this.

IRA FLATOW: All right. You have a story here about another relationship between different species. I’m talking about elephants and dung beetles. How could they be related?

BENJI JONES: So, well, dung beetles famously love dung, and it turns out they actually are quite discerning and they prefer some dung over other dung. And there’s new research showing that dung beetles really prefer elephant dung, partly because elephants produce so much of it. It’s also very nutrient rich. And what this study did is they looked at what would happen if you removed elephants from the landscape, so if elephants go extinct, what does that mean for dung beetles? And the results are pretty incredible.

So researchers excluded elephants from the landscapes. And then they looked at what happened to dung beetles, and they found that there were 2/3 fewer dung beetles and a 1/4 fewer beetle species. And so what this shows is something called coextinction. So if you lose elephants, you lose dung beetles because dung beetles really love elephant dung.

And this is important because dung beetles are super useful on the landscape. They eat dung, they lay their eggs in it, and in that process, they help bury and decompose animal poo. They help disperse seeds. I mean, I love thinking about these little beetles rolling balls of poop. And they’re literally burying seeds. So they’re like squirrels. They’re nature’s planters. So we don’t want to lose dung beetles. And now we know from this research that if we lose elephants, we can lose dung beetles.

And speaking of insects, I heard that you just started a quest to discover a new insect species. What’s going on? Why insects? How do you do this?

BENJI JONES: OK, so over the last few years, one of the topics I’ve been reporting on is species discovery. And what I’ve learned through this is that so much of life is still unknown. So as much as 90% of all animal species globally are still undescribed, which means there’s an opportunity still to discover something new. And that’s especially true in the realm of insects. So there are these insect groups, like flies and certain kinds of wasps, in which the bulk of species are totally unknown to science.

And I got this idea, thanks to a conversation with this fly researcher named Emily Hartop, to try to find something new in New York City, which seems crazy because it’s the most explored place in the world, but because some of these insect groups are still so unknown, even if you’re in the middle of Central Park or Prospect Park, you can still find a new species of, say, fly.

And so what I’m doing is I have set up, with a bunch of partners, a big bug trap in Brooklyn’s Prospect Park and also in Central Park, and over the summer will be collecting as many small flying insects as possible, and then essentially sending them to a lab and sending them to taxonomists to try to figure out if what we found is new. And one of the researchers I’m working with did a similar experiment in LA, and they found over 40 species of flies, new species. And so we feel pretty confident that we will find something new in New York. And I really just want to use that to showcase how unknown the world still is, which I think is exciting. I think that’s inspiring to know that there’s so much out there that we can still discover and hopefully learn from.

IRA FLATOW: You think we can set up a competition between cities around the country, how many new species they can discover in their backyard?

BENJI JONES: Dude, I’m totally game. I’m totally game for this. And honestly, I just want to say, this is not hard to do. Our bug traps– well, I should say it shouldn’t be hard. I struggle to set up this trap myself. It’s essentially just putting out a big tent. And it’s a passive trap, so it does the collection on its own. You just have to leave it open. And so it’s very simple. It’s been used for 100 years. They’re called Malaise traps. And really, anyone can do it. And there is actually a global effort called Bioscan to try to sample life all around the world to discover new things. So if you want to get involved, you can totally set up your own trap and start discovering stuff.

IRA FLATOW: All right, so when do you think this will be over? When can we have you back on to tell us if you found something new?

BENJI JONES: I hope soon. So we will start sending our samples out in a couple of weeks. And at that point, a lab called the Center for Biodiversity Genomics will start analyzing DNA of the specimens that we collect. And we’re hoping by, say, mid-summer, we will have some idea of whether what we have is new. At that point, it needs to go through the formal description process if it is new, which could take time, but we should have some sense of newness by, let’s say, July or August. So I will definitely– I’ll definitely be back to tell you about it.

IRA FLATOW: Well, I want to thank you for taking time to be with us, and I hope you will, and we’ll look forward to it. Best of luck, Benji.

BENJI JONES: Thank you. Thank you for having me.

IRA FLATOW: Benji Jones, senior environmental correspondent at Vox. And if you want the house tour of Benji’s bug trap, head to our Instagram, @SciFri.

FLORA LICHTMAN: Before we go, a wrong we must right. A couple weeks back on the show, we talked about the tunes our appliances are playing, and we mentioned this washing machine ditty. And we kind of ragged on it a little bit.

SPEAKER 1: First of all, it sounded like a fife, and I’m imagining a leprechaun.

SPEAKER 2: If that was ever on my appliance, I’d think I would break it.

FLORA LICHTMAN: OK, what happened next? Well, Team Washing Machine wrung us out. We got loads of listener calls.

SPEAKER 3: I saw all of those points of view were ridiculous, wrong, and completely insulting to my beloved melodic washing machine.

FLORA LICHTMAN: Most importantly, many of you pointed out that the washing machine melody wasn’t some random fife tune.

SPEAKER 4: That jingle is based on the beginning of the Fourth Movement of Schubert’s “Trout Quintet.” [VOCALIZING TUNE]

SPEAKER 5: It is a song called “The Trout,” get it? Trout, water, washing machine?

SPEAKER 6: Far from being irritating, it puts a little worm in your ear and you go away from it happily humming “Die Forelle” by Franz Schubert.

FLORA LICHTMAN: OK, to make things right with all you Schubert stans, we are taking the next few minutes to appreciate the trout with someone who has made a living appreciating Schubert and other 19th century Classical music. Here with us is L. Michael Griffel, a longtime music history teacher and former Chair of the Music History Department at the Juilliard School and an expert in 19th century Classical music.

Michael, thank you for being here. And I feel like I need to start by apologizing. I’m sorry for what we did.

L. MICHAEL GRIFFEL: Well, it’s a pleasure to be here. And what you did, it was a harmless bit of ignorance, but who can blame you? How many people would know the things you know about science?

FLORA LICHTMAN: That’s very, very kind. OK, but tell me a little bit about this piece and what it meant to Schubert.

L. MICHAEL GRIFFEL: Well, Schubert was a prodigious writer of art songs, known as “Lieder” in German, writing about 600 or so of them. And he did this even when he was a very, very young man. Some of his most famous songs come from the time when he’s 15, 16, 17 years old, and he set this song by a poet called Schubart. That’s just a coincidence.

And in Schubart’s poem, the story is about a fish, the harmless little animal who is jumping up and down and enjoying the brook water, and just having fun.

SPEAKER 7: [SINGING IN GERMAN]

And here comes this man who wants to catch the fish and can’t, very easily. So the fisherman muddies up the water. Oh, and then the poor little fish can’t have any more fun and gets caught.

FLORA LICHTMAN: Was this song a banger in the 1800s? Is this the equivalent of the top of the Billboard Hot 100 for people back then?

L. MICHAEL GRIFFEL: Yeah, this was a big hit back then. And so it mattered a lot to him. And in the summer of 1819, with the song having already become very popular, a businessman commissioned Schubert to write a quintet, and the fourth movement uses the song melody as its basis. And it’s interesting to know that among all of Schubert’s chamber music, which includes magnificent works, heavenly works, the “Trout Quintet” was, is, and I think will continue to be the most beloved by the general population. That’s probably why so many were upset, although I think Schubert would have been delighted that even a washing machine is happy to tell us that the clothing is ready or the dishes are ready. And they tell it by using a Schubert song.

[MUSIC PLAYING]

Schubert, by the way, wrote these 600 songs and legions of instrumental pieces all by the age of 31. He passed away at the age of 31, which is incredible.

FLORA LICHTMAN: Wow.

L. MICHAEL GRIFFEL: Incredible. With more than 1,000 pieces composed.

FLORA LICHTMAN: Wow. L. Michael Griffel, the former Chair of the Music History Department at the Juilliard School, thank you so much for coming on the show today. It has been really a treat to swim in these waters with you.

L. MICHAEL GRIFFEL: Well, it’s a great pleasure to be with you. Thank you so much for having me.

FLORA LICHTMAN: That is about all the time that we have for today. If you have a gripe, the listener line is always open. 877-4-SciFri is our number. Have a great weekend. I’m Flora Lichtman.

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