ARI SHAPIRO, HOST:
This week, NPR's looking at how the food we eat every day affects climate change. We're focusing on solutions that cover everything from how we grow food to how we eat it. So let's talk about beef. U.S. beef production is responsible for about 4% of the nation's planet-warming pollution. Some researchers say eating less beef could lower emissions. For Americans reluctant to give up their steak dinners, Harvest Public Media's Elizabeth Rembert investigated whether there's a way to order a burger while keeping your climate conscience clean.
ELIZABETH REMBERT, BYLINE: From her home in eastern Nebraska, Angie O'Brien (ph) does what she can to help the environment. She reduces, reuses and recycles and tries to be more aware of where her food comes from, like beef, which she often buys from nearby ranchers.
ANGIE O'BRIEN: I've just figured if it's a local cow, I always feel like that's a little bit better.
REMBERT: Beef in particular can drive up a person's contributions to climate change. One study from the American Journal of Clinical Nutrition found that swapping out beef can slash your diet's emissions footprint by about half for that day. But O'Brien's not looking to cut the red meat out completely.
O'BRIEN: No. Girl, we're in the beef state (laughter).
REMBERT: For people like O'Brien, who care about their action's impacts on the earth and also think a hamburger sounds really good, is there a way to eat beef sustainably?
DIEGO ROSE: I don't know if I would use sustainable eating of beef in the same sentence.
REMBERT: That's Diego Rose. He leads the nutrition program at Tulane University in New Orleans. His research tallied the environmental impact of nearly 17,000 people's diets for one day. Running down the list, most foods clocked in around the same.
ROSE: And then all of a sudden, we'd hit one that was like 10 times more or a hundred times more than anything else, and invariably, that was beef.
REMBERT: Cow burps are a lot of what's packing the environmental punch. That's according to Aaron Smith. He's an agricultural economist at the University of California Berkeley. You may have heard of cow farts as the culprits.
AARON SMITH: So people like to say farts because it's more fun or funny to talk about, but it really is more burps.
REMBERT: The burps release methane, which is a powerful planet-warming pollution that contributes to climate change. Some ranchers are thinking about how their cattle impacts the environment. About 20 years ago, Jim Knopik switched how he raised cattle on his central Nebraska ranch. He wanted to take better care of his soil and water.
JIM KNOPIK: What I really want is clean water for the next generation and a good environment and good, clean food.
(SOUNDBITE OF FOUR-WHEELER ENGINE RUMBLING)
REMBERT: Knopik is headed out on a four-wheeler to check on his cows. Now, instead of keeping cattle in the same field for months, he rotates them frequently to smaller bits of pasture. It's called mob grazing. And the idea is the cows help the soil by stamping organic material into the ground, and it gives grasses time to recover between grazing. Knopik ushers about 500 cows into a fresh section of pasture by winding up a twine fence. The herd ambles in and gets to work on the tall grasses.
KNOPIK: See how they quieted down? Now they're just busy.
(SOUNDBITE OF COW MOOING)
REMBERT: Knopik says now his soils are healthier, even during past times of drought in Nebraska. These cattle Knopik raises will eventually end up at a feed lot eating grain. Other ranchers and researchers say letting cows eat grass their whole lives may reduce the overall impact cattle have on the environment by improving the soil and using less water. But raising cows a hundred percent on grass could end up having a bigger impact on climate change. For one thing, it takes longer for cows to gain weight when they only eat grass, so they live longer and emit more methane. That's according to Al Rotz, a researcher with the U.S. Department of Agriculture.
AL ROTZ: Strictly from a greenhouse gas standpoint, it's hard to say that grass finishing cattle is good for the environment.
REMBERT: He points out things like improving soil quality and water use also matter to the environment. But ultimately, Rotz says substantially lowering the emissions footprint of U.S. beef is a long shot. He doubts it can ever become carbon neutral, which means emissions are balanced by an equal amount being removed.
ROTZ: Five, 10%, maybe even 15% reduction? Yeah. Fifty percent reduction, carbon neutral? No.
REMBERT: That's why Diego Rose with Tulane University says\ the answer is simple.
ROSE: Yeah, eat less. I mean, if you're trying to reduce your carbon footprint, eat less beef.
REMBERT: That's more doable for Angie O'Brien. She says she might cut back a little bit.
O'BRIEN: Yeah, I can go a few days, but then I'm like, oh, a hamburger really sounds good.
REMBERT: For O'Brien and other beef eaters, eating less can be a part of the solution to lowering their emissions on the dinner plate. For NPR News, I'm Elizabeth Rembert in Nebraska.
SHAPIRO: And you can find our stories all week at npr.org/climateweek, in our podcasts and on the air on your local NPR station. Transcript provided by NPR, Copyright NPR.
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