IRA FLATOW: This is Science Friday, I’m Ira Flatow. A bit later in the hour, the White House is assembling a coalition of climate skeptics to advise the President on climate science. We’ll talk about how that’s shaping up and how the climate is changing in Washington. 

But first, you know the old song, (singing) blue skies smiling at me. Nothing but blue skies do I see. 

Lyrics by Irving Berlin about happy times, I’m sure he sang it much better than I did. But a new study says that under certain extreme conditions of climate change, a certain type of cloud might be gone forever. Blue skies smiling at me? It’s not as cheerful as it sounds. 

Here to tell us more about the sad story is someone who’s never sad, Sophie Bushwick, technology editor at Scientific American. Sophie, nice to have you back. 

SOPHIE BUSHWICK: Nice to be here. 

IRA FLATOW: So researchers say extreme climate change could create conditions where there are no clouds? 

SOPHIE BUSHWICK: So yes, specifically this kind of cloud called stratocumulus. They’re the ones that– they’re kind of low lying and they look sort of flat, almost spread out like a blanket. And they reflect a lot of sunlight. 

But the problem is for them to maintain their integrity, at certain high temperatures the air within them become so turbulent that they would just break up. And researchers have estimated that when or if we get carbon dioxide in the atmosphere at about 1,200 parts per million, the earth will get hot enough that we won’t have any straddle cumulus clouds. And if that happens, the climate could go up by another eight degrees Celsius on top of the existing four. Which would be devastating to life on Earth. 

IRA FLATOW: Well, I guess hopeful news is that– we’re at 400, it has to go to over 1,000 parts. 

SOPHIE BUSHWICK: Right, the problem is that if we don’t do anything that we could be getting close to that area by the end of the century. 

IRA FLATOW: Wow. I don’t even want to think of it. Eight degrees, that is some rise. 

SOPHIE BUSHWICK: That’s a lot, yes. 

IRA FLATOW: That would melt a lot of icebergs. 

SOPHIE BUSHWICK: Yeah, the equator would be pretty much uninhabitable, but the Arctic would be balmy. 

IRA FLATOW: Not good for the Arctic. 

SOPHIE BUSHWICK: No, not good for any place on earth. 

IRA FLATOW: All right, let’s move on to something a little more interesting or hopeful. Researchers genetically modified brewers yeast to make it produce a CBD. 

SOPHIE BUSHWICK: That’s right. So they modified this yeast to make it produce CBD and THC, which are two compounds called cannabinoids found in marijuana. They actually also said that this is a platform for them to make rarer cannabinoids. So marijuana contains more than 100 different of these compounds that fall into this family. But it’s just hard to extract anything except CBD and THC, because those are the ones you find in the highest concentration. 

So they say this is also an opportunity to make all these other compounds, which could have really interesting applications. So CBD gets a lot of attention for potential medical applications. It’s non psychoactive. So taking it won’t get you high. 

But researchers have investigated it. It’s shown promise for treating epilepsy. But there’s also a lot of hype about it and it’s hard to pick through just what it can do until more research is available. 

IRA FLATOW: They say it makes you sleep better, you know, it will actually calm you down or might be helpful in some sort of pain medication too. 

SOPHIE BUSHWICK: Right, the issue is just being able to research it. So it’s still– anything derived from marijuana is still classified as a Schedule I drug. That’s the same category as heroin. 

So CBD researchers are really– they need to get licenses from the federal government and they need to get funding in order to do these investigations. Because at the moment, CBD is being touted as a treatment for so many things. And whenever any single substance people say can cure anything, that’s sort of like a red flag warning. 

IRA FLATOW: Yeah. And brewers yeast, right? They are always talking about using brewers yeast to make all kinds of stuff. 

SOPHIE BUSHWICK: Yes, so not only is brewers yeast– its traditional uses, you can make beer, you can make bread. Which, you know, it’s man’s best friend as a microbe, I guess. But it also has been modified to make a lot of other things. It’s already been modified to make hormones like insulin. And previous studies have actually used it to make opioids as well. 

IRA FLATOW: Speaking of yeast, there’s a controversy brewing. See what I did there? 

SOPHIE BUSHWICK: Ah-ha. 

IRA FLATOW: In the world of evolutionary microbiology. Tell us about that one. 

SOPHIE BUSHWICK: So French scientists have analyzed these, sort of, micro fissures in rocks that they say suggests that they were left by some sort of moving microorganism. Some kind of ancient organism, sort of like slime mold, that moved and left mucus trails. That left these marks in the rock. But if they’re correct that these are not just random cracks, then that would push back the first earliest moving life on Earth to 2.1 billion years ago. Which is 1.5 billion years before we thought. 

IRA FLATOW: And that’s not trivial, is it? I mean, that’s a long time. 

SOPHIE BUSHWICK: That’s a long time. That’s like a rewriting of evolutionary history. 

IRA FLATOW: And so what are the scientists on the other side of the debate saying about that? 

SOPHIE BUSHWICK: So they say that, as Carl Sagan said, extraordinary claims require extraordinary evidence. And that the evidence in this case, they say, is not sufficient. That it’s– that he’s made a good case, but that they want to investigate further and find other sources that would back up this claim. 

IRA FLATOW: Yeah, you always have to look for– yeah. 

SOPHIE BUSHWICK: Yeah, I mean, this is science working the way it should. If someone makes a claim, you should interrogated it, and test it, and see if you can reproduce these results. 

IRA FLATOW: Finally, we’re going to leave our listeners with some food for thought. Which is, researchers know why our brains crave sweets when we’re anxious. I know that is so true of me. 

SOPHIE BUSHWICK: Mm-hm. 

IRA FLATOW: You know, when I’m watching a ball game where the score is wrong or there’s politics, I’m going to that refrigerator because I want to relieve that anxiety. Now we know that. 

SOPHIE BUSHWICK: Yeah, it’s your brain is– it’s because your brain is really greedy. So your brain is hungry. Of all the carbs you eat in a day, your brain consumes half of them. 

IRA FLATOW: Is that right? 

SOPHIE BUSHWICK: That’s right, yeah. So your brain is already using up all this energy. And when you’re stressed out, it increases its energy intake by about 12%. So it basically can bypass the rest of your body, which is signaling, I’m not hungry. I’m at a comfortable energy level. 

And your brain says, no, I need energy right now. And so your body’s reaction to that is like, what’s the quickest form of energy I can have. It’s carbohydrates. And sugary carbohydrates are even better than starchy ones for getting you that quick energy boost. 

IRA FLATOW: So it goes right to junk food. 

SOPHIE BUSHWICK: Yeah, yeah, like if you always crave chocolate when you’ve got a paper due or something. 

IRA FLATOW: Wait, let’s not put chocolate in the junk food. 

SOPHIE BUSHWICK: Allow me to be clear. Chocolate is a magical, wonderful thing, but it’s maybe not the most healthy choice? 

IRA FLATOW: OK, well, I’ll agree with that. Thank you, Sophie Bushwick, technology editor for Scientific American.

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