The foods that do the most damage to our climate

The foods we eat and the ways we produce them damage our planet’s climate.

Emissions from food systems around the world are stopping us from hitting key climate change targets of lower temperatures, according to a recent report in Science. A conservative estimate by the Food and Agriculture Organization of the United Nations puts agriculture’s contribution to total greenhouse gas emissions at 14.5 percent. 

Some experts warn those numbers are too low. They estimate that agriculture contributes to upwards of 37 percent of greenhouse gas emissions, intermingling with the largest sectors that contribute to emissions: energy, industry, and transportation.

It’s easy to point a finger at the massive scale of livestock or rice production, two enterprises that pump large amounts of methane into the atmosphere as a byproduct. Methane traps heat about 80 percent more effectively than carbon dioxide.

The problem could also be pinned on the vast, homogenous swaths of corn, soy, or other row crops that soak up nutrients from the Earth without replenishing them on their own, contributing to declining soil health around the globe and limiting the amount of carbon that can be absorbed in the ground.

It’s not the foods themselves that are damaging the environment. It’s the farming practices.

Or the blame could be placed on foods like almonds and avocados whose trees require large amounts of water to thrive, often more than the climate naturally provides for commercial cultivation. Increased avocado production to match rising popularity in recent years is having some particularly harsh results, leading to water shortages and desertification in Chile.

But it’s important to note that it’s not the foods themselves that are damaging the environment and climate. It’s the farming practices.

A global variety of agricultural implementations from the ways we handle fertilizers to a lack of biodiversity negatively impact the climate, and many of these individual practices interconnect.

“Everything is related to everything,” Sonja Brodt said.

Brodt is the academic coordinator of University of California’s Sustainable Agriculture Research and Education Program. One of the program’s focuses is on climate resilience and helping the people who produce our food improve their environmental impact.

Broadly, there are two different sides to agriculture’s impact on climate change, Brodt said.

“There is the emissions side that comes partly from fossil fuel use and partly from things like nitrous oxide and methane emissions,” she said. “The other side is looking at the soil globally as a key resource. Right now, a lot of agricultural soil is a net emitter of carbon dioxide. How can we move it closer to being a sink just like the forests are for carbon?”

In looking at these two sides and considering the intersectionality of so many methods, a significant amount of the damage inflicted on the planet through farming is rooted in our seemingly insatiable appetite for meat, namely beef.

Overfarming cattle

Livestock and their manure account for around 63% of agricultural greenhouse gas emissions, the UN estimates. The bulk of this percentage stems from gas produced by cows during digestion. Basically, they’re burping out methane. The rest of the issue boils down to manure and how it’s managed.

“But it doesn’t mean every dairy farm is terrible,” Brodt said. “The devil is in the details.”

The world produces roughly 71.6 million tons of beef and buffalo every year.

An individual farm, if it handles its manure in the most sustainable way by feeding it back into the Earth in small amounts and storing/distributing the excess properly, can drastically reduce the amount of nitrogen that seeps into the atmosphere. Excess nitrogen that isn’t used by plants is released into the atmosphere in the form of nitrous oxide, a gas 300 times more potent than carbon dioxide.

But at larger scales, sustainable manure management is untenable. Massive factory farms focused on beef production can have hundreds or even thousands of heads of cattle. They produce an unreasonable amount of manure, not to mention the methane they’re blasting into the air.

To make room for all that pasture, forests are being cut down at alarming rates. Those ecosystems which help absorb carbon from the atmosphere are being cleared by 50,000 acres a day, mostly for livestock.

Ricardo Salvador, director and senior scientist in the Union of Concerned Scientists‘ Food and Environment Program, said that reducing meat consumption and meat production could help stem the negative impact farming has on the climate.

“If we could get away from this vector where we think everybody’s entitled to eat as many hamburgers as they want as so therefore we’re all out in terms of beef production, that would help a great deal,” he said.

The world produces roughly 71.6 million tons of beef and buffalo every year, with the three biggest producers being the United States, Brazil, and China. Globally, production has more than doubled since the 1960s, Our World In Data shows.

The animals themselves are not directly damaging the planet. They weren’t much of a problem until we started breeding them in such huge numbers for beef. If people are willing to accept the trade-off of eating less meat for the sake of the environment, we could farm cattle more methodically and in smaller numbers to reduce the industry’s carbon footprint to zero.

“There are sustainable ways of producing beef under fairly intensive management of paddocks where you’re growing vegetation that’s concentrated and helps the animals increase weight,” Salvador said. “As you rotate them through these intensively managed paddocks, what you do is contribute to a system where you have perennial grazing and you’re sustainably returning nutrients to the soil.”

One system is called adaptive multi-paddock grazing, in which livestock are brought to graze in one section of land — a paddock — and then aren’t returned to that patch for weeks, months, or a whole year, allowing the soil and plants to process their waste and rest.

Iowa farmer Zack Smith, who Salvador spoke with earlier this year, has been testing a sustainable system in which he raises livestock right alongside corn, combining two facets of farming that are typically completely separated. Not only does that reduce his risk as an operator by diversifying his enterprises, it allows him to reduce inputs like fertilizers by using a more natural process.

This broader dual-pronged approach of reducing livestock production and changing the method by which they’re farmed would also cut a massive wedge out of a sector of agriculture that mostly serves to feed the world’s livestock.

Monocropping corn, soybeans, and wheat

Over one-third of cropland around the world is used exclusively to produce crops for livestock and biofuels, and much of it grown using monocropping. Row crops like corn, soybeans, and wheat are frequently monocropped, meaning they are the only crop grown on that land year after year. Monocropping can damage what used to be healthy soil by sucking up nutrients and cutting down on biodiverse organic material available to organisms in the ground.

Soil that isn’t properly fed with a variety of organic material will lose the fungi, microbes, and bacteria that process it and feed it back into vegetation. As the ecosystem degrades, it loses its ability to retain life and hold water. Underfed and overused soil erodes. In droughts, it turns to dust. In heavy rains or floods, it gets swept away, cutting gullies through farmland.

These cropland gashes are the signs of lost soil. In Iowa, a state smack dab in the middle of the Corn Belt, corn farmers are losing millions of tons of topsoil every year due to these practices, Tom Philpott describes in an excerpt of his book Perlious Bounty, published through Modern Farmer.

Monocropping and the goal of stretching out enterprises like corn as far as the eye can see has been pushed by corporations and policy makers as a means to increase production and reduce labor through the industry, a topic farmer and activist Wendell Berry covers extensively in his book The Unsettling of America. He describes an industrialized system propped up since the mid-19th century by people more interested in profit margins than preserving the land or jobs across the U.S.

“We’ve invested a great deal in learning about the technologies that have given us the industrial system,” Salvador said. “They were focused on treating the outdoors as if it was a factory rather than a set of ecological cycles.”

That factory analogy can be seen further in how many monocrop farmers feed nutrients back into the soil: synthetic fertilizer. Spreading synthetic fertilizer is quick and easy, but the production of it burns a lot of fossil fuel.

The corn, soy, and wheats of the world wouldn’t be a problem if they were grown responsibly.

“Synthetic nitrogen fertilizer has such a high carbon footprint in the manufacturing of it,” Bordt said, “and then when you put it on the soil, it can release nitrous oxide emissions.”

It’s a double whammy of greenhouse gas emissions, but unfortunately, nitrogen is a vital part of farming.

“The reason people use it is because you do need to add nitrogen to soil to keep using a field over time,” Brodt said. “You can’t just not do anything. It’s an essential nutrient.”

The corn, soy, and wheats of the world wouldn’t be a problem if they were grown responsibly. Brodt mentioned organic inputs like manure and compost can feed nutrients like nitrogen back into the soil when applied correctly. Cover crops, plants that are grown when a field would otherwise be bare, can feed nutrients back into the soil too and retain the life and structure of the soil in off-seasons.

Not only that, introducing a little biodiversity into a field can allow it to sequester more carbon, turning agricultural systems into carbon sinks rather than emitters.

Deforestation

Many forests are effective in sequestering carbon, meaning they pull carbon dioxide out of the air and process it for plant growth while sending excess carbon down into the soil. The Amazon rainforest alone absorbs more than 2 billion tons of carbon every year.

To make way for crops, natural landscapes including forests are frequently cleared by humans. Deforestation has reduced the Amazon rainforest’s size by 20%. It’s something we’ve been doing since the dawn of agriculture more than 10,000 years ago. If we’re not going to eat anything off of a particular bush or tree, why keep it around?

Those plants, even if we don’t use them for food, help create a healthy ecosystem. By looking at biodiverse forests as a sort of holistic, natural guide for farming, we can push agriculture into a more sustainable or even regenerative direction. The idea of intentionally adding trees and shrubs into an agricultural operation is called agroforestry.

Instead of working against the land, farmers could work with it.

“For a lot of us, our main calories are from annual crops but you can still bring trees into those systems on the edges or through different agroforestry systems that integrate different crops,” Brodt said. “It’s that long-term woody component basically that’s going to store carbon more.”

There are natural ecological cycles that exist whether or not humans ever existed, Salvador explained. 

“The hydrological cycle, the carbon cycle, the oxygen cycle, the sulfur cycle. Instead of interrupting that so that it becomes discontinuous and therefore you need to purchase the resources that you’re using to enable agricultural productivity, you can essentially manage the ecology,” he said.

Instead of working against the land to increase short-term yields at the long-term detriment of the land, farmers could work with it.

“If I understand and I actually work with the bacterial and microbial populations in the soil, I can keep the integrity of the system alive and reduce the cost of producing because I don’t have to purchase all these external inputs,” Salvador said. “I can recycle nitrogen. I can recycle the sulfur. I can recycle basically all of the carbon that right now is creating all the greenhouse gas issues.”

Even though agroforestry is not the most popular form of agriculture in places like the U.S., it’s actually quite doable. These kinds of systems feed 70% of the world’s population, according to ETC Group, which means less reliance on deforestation and synthetic fertilizers, and better soil health in these areas.

By trying to restore these more natural cycles, it could help disrupt other damaging agricultural systems because everything is connected. By doing one thing better, it can have a ripple effect across the agricultural web and reduce its negative climate impact while increasing its positive impacts.

There are ways farming practices can be changed for the better on both micro and macro levels. We can reduce demand for meat, erase vast methane emissions from flooded rice paddies by using alternative growing methods, bring more biodiversity into farmland, ease reliance on synthetic fertilizers, or even just allow some trees to grow throughout our fields.

What we can do to eat more sustainably?

There is a lot that farmers can do to improve agriculture’s impact on the climate, but what about people who aren’t farmers? 

1. Change your diet

This can be a tough change for some people, but it’s the biggest tool we have at making a significant impact on agricultural systems. By doing things like reducing meat consumption, we reduce demand for beef, pork, and chicken, and thus reduce the number of livestock produced. That will cause a ripple effect. Less feed needs to be produced and we can slow or stop deforestation for livestock, making a dent in agriculture’s contributions to climate change.

2. Support local small farms

There are small farms all over the place that produce at a scale that is sustainable and using methods that are better for our soils, our air, our food, and our water. Of course, no farms are perfect, but choosing to buy produce from smaller, more local producers cuts down on things like transportation and packaging that utilize fossil fuels.

If you can find organic farms nearby, choosing them over farms that rely on synthetic fertilizers will directly impact the corporations that produce synthetic fertilizers. If farmers see a demand for organic food, they’ll be encouraged to use methods that don’t utilize synthetic fertilizers, which takes money out of the pockets of those corporations and reduces the power and capital they use to lobby governments and keep their productions going at ever increasing rates, Salvador explained.

3. Vote responsibly

Instead of voting for politicians that promise to cut regulations for agriculture, environment conservation, and the climate, support candidates who understand the issues we’re facing and want to support producers who grow food sustainably. The U.S. Department of Agriculture does actually care about these things and has initiatives that address many problems that agricultural systems cause, but these agencies need funding and support from politicians.

4. Do it yourself

It’s much easier to grow food organically and sustainably yourself than make other people change the way they operate. Participate in or support community gardens, grow some herbs on your windowsill, or start planting vegetables in your yard, if you have one. By becoming part of the system that produces food, you can control how it’s produced, even if it’s just a little bit. Hell, quit your job, buy, rent, or borrow some land, and support your community in a meaningful way.

All of it helps, and as we understand more about how our planet, its plants, and its soil thrive, we can treat it in a way that’s sustainable.