06/23/2017

Climate Change Could Lead To Coffee Crisis

4:46 minutes

Coffea arabica. Credit: Malcolm Manners/flickr/CC BY 2.0

When it comes to coffee, Ethiopia is sacred ground.

It’s the home of Coffea arabica — one of the most popular species of coffee bean. And in Ethiopia, coffee is a major part of the economy: It makes up about a quarter of the country’s export earnings, and around 15 million farmers make a living farming the crop.

But as the climate changes, scientists predict Ethiopia’s coffee spigot will slow to a drip in some areas. According to a new study published in “Nature Plants,” 39 to 59 percent of the land currently used to grow coffee could eventually become unsuitable for growing the crop.

“That is a really significant reduction, and that’s from now until the end of the century,” says Aaron Davis, a biologist at the Royal Botanic Gardens, Kew, in London, and a co-author on the study. The culprits? Rising temperatures and decreasing rainfall, he explains.

[Climate change is threatening your breakfast.]

“What we’ve seen from climate station data is that there has been a steady … decade-by-decade increase, in the average temperature in Ethiopia,” he says, “and in some cases, even from the 1950s onwards, a decrease in rainfall in some of the coffee growing areas.”

In the future, Ethiopian farmers could turn to more drought-resistant species of coffee. “[But] the real issue for Ethiopia is that its specialty is Arabica coffee,” Davis says, “and that’s the coffee that gives a wonderful flavor profile, so that’s the coffee we love.”

Davis and his team based their projections on data from climate models and high-resolution satellite images — supported, as they write in the study, by “rigorous ground-truthing.” But the researchers’ stark predictions are seeded with a bit of hope: As the climate changes, other land in Ethiopia might actually become more suitable for growing coffee.


Find out what’s happening on Science Friday…on Thursday. Subscribe to our preview newsletter.


“The coffee-growing landscape of the world, and Ethiopia, is very flexible — it changes over time,” Davis says. “What we see, even under the threat of climate change, [is] if you move coffee to the right places you could actually increase productivity at the end of the century up to 400 percent — a massive increase.”

But some Ethiopian coffee farmers are already seeing the negative effects of climate change, according to a Kew press release. What’s more, many won’t have the means to follow coffee to where it grows next. “Considerable numbers of farmers would need to diversify away from coffee,” the press release states, “whilst others would need to take up coffee growing for the first time.”

“There are other scenarios, there are other things that can be done,” Davis says. “But it basically means … moving coffee plantations to higher ground where the conditions are cooler.”

—Julia Franz (originally published on PRI.org)

Segment Guests

Aaron Davis

Aaron Davis is Senior Research Leader for Plant Resources at the Royal Botanic Gardens, Kew, in Richmond, England.

Segment Transcript

IRA FLATOW: And now it’s time to play Good Thing Bad Thing.

[MUSIC PLAYING]

Because every story has a flip side. Now it’s time for some Coffee Talk. We’re going to talk amongst ourselves. You coffee aficionados know that Ethiopia is the birthplace of the bean, the cradle of coffee. And about 15 million farmers in that country depend on the crop for their livelihood.

It appears that, like many things, climate change will likely have a big influence on the future of the coffee crop. Botanists have looked at the effects of climate change on Ethiopian coffee, and the outlook is not good.

But there may be ways to save the crop. The results were published this week in the journal Nature Plants. My next guest is an author on that study. He’s here to help us break it down. Aaron Davis, senior research leader of plant resources at the Kew Royal Botanic Gardens in Richmond, England.

Welcome to Science Friday.

AARON DAVIS: Thank you. Hello.

IRA FLATOW: Do you call yourself a coffee biologist?

AARON DAVIS: Well, I do. Yes, yes.

IRA FLATOW: All right, let’s talk coffee. Let’s start with the not so good news from your study. How much will climate change affect Ethiopian coffee?

AARON DAVIS: Well we provided quite a range of projections and scenarios. The worst case scenario is a 60% reduction in the land that’s suitable for growing coffee.

IRA FLATOW: 60%.

AARON DAVIS: That is a really significant reduction. And that’s from now until the end of the century.

IRA FLATOW: Wow. I’m just shocked at hearing 6-0, 60%.

AARON DAVIS: Yeah, that’s the worst case.

IRA FLATOW: That’s the worst case.

AARON DAVIS: That’s really the worst case scenario.

IRA FLATOW: Well what keeps– well how will the coffee be affected? What happens to the climate that changes that?

AARON DAVIS: Well it depends on where you are across the world. But for Ethiopia, the real issue is rising temperatures and decreasing rainfall. What we’ve seen from climate station data is that there has been a steady year on year increase, or decade by decade increase, in the average temperature in Ethiopia. And in some cases, even from the 1950s onwards, a decrease in rainfall in some of the coffee growing areas. So the decrease in rainfall and the increase in temperatures make conditions for growing coffee unsuitable in some areas.

IRA FLATOW: Now you said in some areas, because I understand there is some good news about how the coffee can be grown in a changed climate.

AARON DAVIS: That’s right. You know, one of the surprises for us was that actually it’s not all bad news. The coffee growing landscape of the world, and Ethiopia, is very flexible. It changes over time. But what we see, even under the threat of climate change, if you move coffee to the right places you could actually increase productivity at the end of the century up to 400%, a massive increase.

IRA FLATOW: Now what kind of shifting does that require?

AARON DAVIS: So there are other scenarios, there are other things that can be done. But it basically means moving– in the main, moving coffee plantations to higher ground where the conditions are cooler.

IRA FLATOW: What about growing more drought-resistant versions of the coffee? Is that possible?

AARON DAVIS: That’s also feasible. The real issue for Ethiopia is that its speciality is Arabica coffee, and that’s the coffee that gives a wonderful flavor profile. So that’s the coffee we love. You can replace it with other species. The trouble is they just don’t taste the same.

IRA FLATOW: I didn’t know that Ethiopia was the coffee cradle of the world.

AARON DAVIS: Indeed it is, yeah. Southern Ethiopia and South Sudan, that’s the natural home of Arabica coffee.

IRA FLATOW: Wow, fascinating. Thank you very much, Dr. Davis, for taking time to talk with us today.

AARON DAVIS: You’re very welcome.

IRA FLATOW: Aaron Davis, senior research leader of plant resources at the Kew Royal Botanic Gardens in Richmond, England.

We’re going to take a break, and when we come back: Cephalopod Week. Yes, it’s here. And if you’re a sucker for cool technology– get it– you’ll be amazed at what engineers have learned by studying squid. All the things you can make if you learn how a squid does it then maybe you can imitate it. So coming up after the break: Cephalopod Week.

We’d love to hear from you. Stay with us, 844-724-8255. We’ll be right back after this break.

Copyright © 2017 Science Friday Initiative. All rights reserved. Science Friday transcripts are produced on a tight deadline by 3Play Media. Fidelity to the original aired/published audio or video file might vary, and text might be updated or amended in the future. For the authoritative record of ScienceFriday’s programming, please visit the original aired/published recording. For terms of use and more information, visit our policies pages at http://www.sciencefriday.com/about/policies/

Meet the Producer

About Alexa Lim

Alexa Lim is a producer for Science Friday. Her favorite stories involve space, sound, and strange animal discoveries.

Explore More