Researching How To Fight Climate Change With Geoengineering

Dec 17, 2017
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What if we could fight climate change by manipulating our environment, like spraying sulfur into the stratosphere or brightening clouds? Those are two ways to reflect light back into space and reduce global warming. It's called geoengineering, and there's a new bill in Congress to research this and the potential risks. Congressman Jerry McNerney, Democrat of California, introduced the Geoengineering Research Evaluation Act, and he joins me now. He's a member of the House Committee on Science, Space and Technology. And by the way, he's also an engineer, and he has a Ph.D. in mathematics. Congressman, welcome to the program.

JERRY MCNERNEY: Well, thank you.

GARCIA-NAVARRO: So can you just run through what exactly we're talking about when we talk about geoengineering the planet?

MCNERNEY: Sure. There's two sorts of categories. The one category is removing carbon from the atmosphere. You can do that by planting a lot of trees. You can do that by trying to seed the ocean to grow more carbon-absorbing plants like seaweeds. And then, on the other hand, there's what they call albedo modification, which is reducing sunlight. One category that is cloud brightening - where you try to add more vapor to the atmosphere, so the clouds turn whiter and reflect more sunlight. And then the other one is actually putting sulfur particles into the atmosphere. The sulfur particles are very reflective in that they will reduce sunlight that gets through to the Earth. Those are the sort of broad categories.

GARCIA-NAVARRO: I'm sure a lot of listeners are also wondering about the unintended consequences of tampering too much with nature. You know, what could possibly go wrong? I've seen the movie.

MCNERNEY: (Laughter) Plenty could go wrong. But I think the biggest thing is that we might change the climate patterns enough to disrupt national production of wheat or food. It could cause severe flooding and severe droughts in certain parts of the world. So I think the risks are very, very high, and we need to have a clear understanding of what the science tells us about these projects.

GARCIA-NAVARRO: Why geoengineer at all? Isn't it better to simply try and cut carbon emissions and tackle global warming that way?

MCNERNEY: Oh, absolutely. We have to reduce carbon emissions first. That's our first priority. That's the thing we have to do with all vigor. But, you know, it takes years or decades for carbon buildup in the atmosphere to have a noticeable impact. And so we're just on the leading edge of climate change, and there's about 10 years of carbon emissions out there that haven't even impacted us fully yet. So we may be in for some truly catastrophic changes. We need to know what the alternatives are.

GARCIA-NAVARRO: Do you think we're really at a place where some of these big science ideas that seem something out of science fiction are really now the only way forward, maybe, to help the planet?

MCNERNEY: We might be, Lulu. We might be. If we start seeing sea levels rise rapidly, then we might be forced into action like this. I hate to say that, but it's true. Isn't there an old saying that if you're in a hole, stop digging? Well, we're clearly in a hole now. Climate change is becoming more obvious, and if we don't stop emissions or reduce emissions, then it's just going to accelerate. So we have to know what our options are.

GARCIA-NAVARRO: Congressman Jerry McNerney of California, thank you for joining us.

MCNERNEY: Thank you, Lulu. Appreciate it. Transcript provided by NPR, Copyright NPR.