This Scientist Aims High To Save The World's Coral Reefs Ken Caldeira is trying to come up with a big solution to the problem of increasingly acid oceans: antacids for coral reefs. That might keep the reefs from being destroyed by humans' use of fossil fuels. And that's not his only big idea. But even Caldeira admits that his audacious plan could fail.
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This Scientist Aims High To Save The World's Coral Reefs

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This Scientist Aims High To Save The World's Coral Reefs

This Scientist Aims High To Save The World's Coral Reefs

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This is ALL THINGS CONSIDERED from NPR News. I'm Robert Siegel.


And I'm Audie Cornish.

More than 12,000 research papers in the scientific literature make reference to the work of one man: Ken Caldeira. That makes him one of the most influential scientists in the world of climate change. He's especially worried about the fate of coral reefs, which could suffer as the carbon dioxide we put into the air gets soaked up by the world's oceans.

NPR sent science correspondent Richard Harris to Australia's Great Barrier Reef to spend some time with Caldeira, a scientist who thinks big.


RICHARD HARRIS, BYLINE: For a guy who has spent most of his career behind a computer screen, Ken Caldeira looks pretty nimble as he picks his way across a beach of coarse coral. He's wearing tattered nylon shorts and a floppy sun hat over his short curly hair. And he's helping a band of young scientists and volunteers load boats to take their gear out to an experiment on the One Tree Island lagoon.

KEN CALDEIRA: OK, we'll be right behind you.

HARRIS: On this expedition, he's hoping to find out whether he can reverse the damage that carbon dioxide is doing to the world's magnificent coral reefs. We pour billions of tons of carbon dioxide into the air and a lot of it soaks into the ocean, making the water more acidic. That stunts the growth of coral. His team is pouring antacid into one small stretch of reef to see if they can reverse that process.

CALDEIRA: So what are these other snorkly, masky things?

HARRIS: This is not where Caldeiria thought he'd be after he graduated from Rutgers with a BA in philosophy back in 1978. He started out writing software for Wall Street. But after a few years, he volunteered on a scientific expedition to study crocodiles in Latin America, and that sparked his interest in field work.

CALDEIRA: And at the same time, I saw a newspaper article in The New York Times where there was discussion of the ice sheets might melt due to CO2 and global warming. And so I thought, well, this is an important issue and so I went to New York University and started studying climate change.

HARRIS: As it turns out, most of his research involves asking big questions, running some computer simulations and getting approximate answers. Caldeira likes to ask these overarching questions and his answers can make headlines.

CALDEIRA: My work tends to be broad-brush and high-level analyses. I always tell my post-docs and graduate students that we always try to say the first word on a subject, not the last word on a subject.

HARRIS: Science wouldn't really work if everyone tried to go after the flashy findings and not fret about chasing down all the details. But big-picture thinkers like Caldeira also help drive the field. Over the years, he's calculated what it would take to cool the planet by spraying reflective particles into the atmosphere. He's calculated just how much clean energy production you'd need to replace all the fossil fuels we're using.

But for all that, he loves being out on a reef doing first-hand research. And he has license to do this because he works at an unusual place. The Carnegie Institution for Science was endowed by industrialist Andrew Carnegie more than a century ago, so Caldeira worries less about money than other scientists do.

CALDEIRA: My job offer letter said make important scientific discoveries. And they basically give me some resources and leave me alone to make important scientific discoveries.

HARRIS: His lab is on the Stanford campus. And his boss gives Caldeira free range to take on risky projects like this. Here, he's trying to measure a tiny improvement in this reef and he may simply not be able to detect it.

CALDEIRA: This is how the science gets pushed forward by people taking risks. And maybe it will work and we'll be lucky and maybe it won't.

HARRIS: In the world where science is often driven by a researcher's ability to get government grants, taking a risk like this is a luxury, but when Caldeira steps back to look at the big picture, that leaves room for some startling insights. For example, it might seem that our vast skies have an endless ability to hold the billions of tons of carbon dioxide we put into it every year. But here's how Ken Caldeira visualizes it.

CALDEIRA: If you were to compress the entire atmosphere down so it was the density of water, it would only be 30 feet deep. And so it's like all the stuff we're throwing into the atmosphere we're throwing into an ocean that's only 30 feet deep.

HARRIS: In fact, when you look at the chemistry of the actual oceans, the carbon dioxide is already making a measurable change. It reacts with seawater and turns into carbonic acid, and that has made the oceans 30 percent more acidic than they were before the Industrial Revolution.

CALDEIRA: And this is a scale of change that hasn't happened for, you know, since the dinosaurs became extinct. And so, we're making radical transformations to ocean chemistry that go far beyond what most organisms have experienced in their evolutionary history.

HARRIS: Coral reefs were wiped out the last time this happened. Caldeira's Ph.D. work back in the 1980s showed that it took hundreds of thousands of years for the reefs to recover.

Out here on One Tree Island, on Australia's Great Barrier Reef, Caldeira and his crew gather every morning in the communal kitchen. They guzzle coffee, crunch cereal, fight off the sugar ants and plan their day. Many of the floors in this rustic outpost are simply gravel-sized coral. Noddy terns, which roost everywhere, add their own special flavor to the drinking water, which is collected from the roof when it rains and stored in cisterns.

The place feels magical but the reef's peril is palpable. Caldeira thinks about this and he ponders what to do about it. It might be possible to save tiny patches of coral reefs by pumping acid-neutralizing chemicals on them. But it's simply not practical to scale that up, even for a single reef. Instead, Caldeira keeps coming back to another big-picture solution and that is to stop burning fossil fuels. Yes, energy will cost more and as a result, there's huge resistance to this idea.

But Caldeira is hoping people will change their views if they simply frame the issue a different way.

CALDEIRA: Decades ago, everybody was smoking cigarettes and it was acceptable to smoke cigarettes indoors. And there was a phase change in social acceptability, where now it is no longer acceptable to dump your cigarette smoke in air that somebody else is going to breathe. And I think we can achieve the same thing with carbon dioxide emissions, where it just becomes socially unacceptable to dump your industrial waste in the atmosphere.

HARRIS: Caldeira is not optimistic that politicians will make this change. And he's not planning to take to the streets. He tried that back in 1982 when he helped organize a huge protest against the nuclear arms race. He's moved on from that strategy. Now, he says, it's time to pay less attention to the problem and more to the solutions.

CALDEIRA: For me, the problem is clear and the solution is in transforming our energy system. And for young people coming into science today, my recommendation would be to work on developing improved energy systems. And I wouldn't advise people to go into climate science. I think it's fundamentally a solved problem.

HARRIS: In fact, Caldeira makes this case to Microsoft founder Bill Gates, who sometimes calls on him for advice. If science and technology can make clean energy cheaper, he says, that would make it easier for people to look at the atmosphere differently, not as a waste dump but as a vital part of our planet.

Richard Harris, NPR News.


SIEGEL: This is NPR News.

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