Why agriculture is a tough climate problem to solve

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As a climate reporter, I'm all too aware of the greenhouse-gas emissions that come from food production. And yet, I'm not a vegan, and I do enjoy a good cheeseburger (at least on occasion).

It's a real problem, from a climate perspective at least, that burgers taste good, and so do chicken sandwiches and cheese and just about anything that has butter in it. It can be hard to persuade people to change their eating habits, especially since food is tied up in our social lives and our cultures.

We could all stand to make some choices that could reduce the emissions associated with the food on our plates. But the longer I write about agriculture and climate, the more I think we're also going to need to innovate around people's love for burgers-and fix our food system not just in the kitchen, but on the farm.

If we lump in everything it takes to get food grown, processed, and transported to us, agriculture accounts for between 20% and 35% of annual global greenhouse-gas emissions. (The range is huge because estimates can vary in what they include and how they account for things like land use, the impact of which is tricky to measure.)

So when it came time to put together our list of 15 Climate Tech Companies to Watch, which we released earlier this month, we knew we wanted to represent the massive challenge that is our food system.

We ended up choosing two companies in agriculture for this year's list, Pivot Bio and Rumin8. My colleague James Temple and I spoke with leaders from both these businesses at our recent Roundtables online event, and it was fascinating to hear from them about the problems they're trying to solve and how they're doing it.

Pivot Bio is using microbes to help disrupt the fertilizer industry. Today, applying nitrogen-based fertilizers to fields is basically like putting gas into a leaky gas tank, as Pivot cofounder Karsten Temme put it at the event.

Plants rely on nitrogen to grow, but they fail to take up a lot of the nitrogen in fertilizers applied in the field. Since fertilizer requires a ton of energy to produce and can wind up emitting powerful greenhouse gases if plants don't use it, that's a real problem.

Pivot Bio uses microbes to help get nitrogen from the air into plants, and the company's current generation of products can help farmers cut fertilizer use by 25%.

Rumin8 has its sights set on cattle, making supplements that help them emit less methane, a powerful greenhouse gas. Cows have a complicated digestive system that involves multiple stomachs and a whole lot of microbes that help them digest food. Those microbes produce methane that the cows then burp up. It's really rude of them," quipped Matt Callahan, Rumin8's cofounder and counsel, at the event.

In part because of the powerful warming effects of methane, beef is among the worst foods for the climate. Beef can account for up to 10 times more greenhouse-gas emissions than poultry, for example.

Rumin8 makes an additive that can go into the food or water supply of dairy and beef cattle that can help reduce the methane they burp up. The chemical basically helps the cows use that gas as energy instead, so it can boost their growth-a big benefit to farmers. The company has seen methane reductions as high as 90%, depending on how the cow is getting the supplement (effects aren't as strong for beef cattle, which often don't have as close contact with farmers and may not get as strong a dose of the supplement over time as dairy cattle do).

My big takeaway from our discussion, and from researching and picking the companies on our list this year, is that there's a huge range of work being done to cut emissions from agriculture on the product side. That's crucial, because I'm personally skeptical that a significant chunk of the world is going to quickly and voluntarily give up all the tasty but emissions-intensive foods that they're used to.

That's not to say individual choices can't make a difference. I love beans and lentils as much as the next girl, and we could all stand to make choices that cut down our individual climate impact. And it doesn't have to be all or nothing. Anyone can choose to eat a little bit less beef specifically, and fewer meat and animal products in general (which tend to be more emissions-intensive than plant-based options). Another great strategy is to focus on cutting down your food waste, which not only reduces emissions but also saves you money.

But with appetites and budgets for beef and other emissions-intensive foods continuing to grow worldwide, I think we're also going to need to see a whole lot of innovation that helps lower the emissions of existing food products that we all know and love, including beef.

There's no one magic solution that's going to solve our climate problem in agriculture. The key is going to be both shifting diets through individual and community action and adopting new, lower-emissions options that companies bring to the table.

Now read the rest of The SparkRelated reading

If you missed our Rountables event Producing Climate-Friendly Food," you can check out the recording here. And for more details on the businesses we mentioned, read our profiles on Pivot Bio and Rumin8 from our 2024 list of 15 Climate Tech Companies to Watch.

There are also some fascinating climate stories from the new, food-focused issue of our print magazine:

• Some companies want to make food out of thin air, with the help of microbes.
• Food demand in Africa is on the rise-indigenous crops could help feed people while also being more climate resilient.
• The world is seeing record-breaking temperatures, and farmworkers are especially vulnerable to the worsening conditions. Researchers are developing a sensor to help protect them.

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Aspen Aerogels is making super-light materials that can help suppress battery fires, and the company just got a huge boost from the US Department of Energy. Read more about the $670.6 million loan and the details of the technology in my latest story.

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