Planet Earth is basically a farm. Livestock cows, pigs, and sheep account for 96% of all the land mammals on Earth (excluding humans), and over half of all habitable land is used for agriculture. Little surprise then that food production accounts for nearly a third of the planet’s greenhouse gasses, and a similar percentage of the average American household’s carbon footprint.
As we stampede into a warmer future, what and how we eat will play a big role in whether we can remain within the planet’s carbon budget. But changing people’s behavior and diets is difficult, and likely to be slow compared to the progression of climate change. That begs the question, is there any path to global decarbonization that can accommodate bacon cheeseburgers and milkshakes, or is it tofu all the way down?
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Yes. Your Diet Isn’t The Most
Pressing Problem
1. We’ve been told that we should change our diet. But the math can tell another story. An international team of researchers set out to quantify the climate benefits of three distinct approaches: using technology to reduce and sequester carbon on farms; changing diets to low-carbon foodstuffs; and reducing food waste. In a recent PLOS Climate paper, they calculated that reimagining agriculture to prioritize carbon capture could sequester tens of billions of tons each year through agroforestry (planting trees on farms), farming seaweed, and enhanced rock weathering, without harming yields. Together with efforts to reduce carbon emissions, such as more sustainable fertilizers and feed additives to reduce methane, agriculture could have an enormous impact on emissions without anyone having to change their diet. In fact, the researchers estimate that if just half the farms in the world adopt all the technologies they identify by 2050, agriculture will be net-negative, offsetting 13 gigatons of CO2.
Source: Almaraz M et al. Model-based scenarios for achieving net negative emissions in the food. PLoS Climate 2023.
2. We’ve been told to waste less of our food. If food waste was a country, its carbon footprint would be larger than all but the US and China. But it’s far more about farms, trucks and warehouses than those moldy oranges in your fruit bowl. A recent meta-analysis by the University of Oxford found that supply chains waste and spoil about 15% of all the calories produced on the world’s farms, and poorer countries waste a lot more food than richer ones due to a lack of refrigeration. This fascinating article by Nicola Twilley in the New Yorker shows how simply upgrading the “cool chain” in Africa could be a big win for the climate.
3. We’ve been told to eat local. Before you beat yourself up reaching for a tropical banana rather than a local apple, you should know that food miles really don’t matter. Food transport is only a small contributor to emissions, accounting for less than 10% of the carbon footprint for most products and an even smaller proportion for the largest emitters, according to Our World in Data. The one exception is air-freighted food—such as some off-season asparagus, berries, and green beans.
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No. What You Eat Really Counts
1. Expecting the entire agriculture system to focus on carbon instead of profit is unrealistic. Some high-tech sequestration technologies will certainly roll out in the years ahead but it’s going to be a long, tough process. The problem is that the biggest gains for the climate, such as seaweed farming, will require lots of study, huge political will, and immense capital to deploy globally. Carbon reduction efforts are far more realistic—and often even pay for themselves. Absent ambitious planetary-scale efforts to sequester carbon, the same PLOS Climate paper noted that consumers changing to a plant-based diet could deliver a gigaton more of savings than all the farm carbon reductions added together.
Source: Almaraz M et al. Model-based scenarios for achieving net negative emissions in the food. PLoS Climate 2023.
2. Anything but cows. Chocolate and coffee are far from climate heroes, but the scale of the cattle industry, and the impact of all those bovine burps so bad, that swapping meat for vegetarian alternatives over the next fifteen years would get us halfway to meeting the Paris Climate Agreement. It would even stabilize greenhouse gas emissions by 2030—no new technologies or drastic lifestyle changes required.
3. Don’t be fooled by greenwashing. Earlier this year, the USDA allowed Tyson Foods to label some of its ground beef “climate friendly,” due to it having a carbon footprint supposedly 10% smaller than conventional beef. That got Brian Kateman, president of the Reducetarian Foundation, all riled up. He blasted the designation in Time Magazine, noting that not only is it self-certified, even beef with higher than average emissions could qualify for it. “The program isn’t just useless; it could even harm the environment further,” wrote Kateman. “The low bar to certification could de-incentivize producers from making bigger changes and lead consumers to complacency.”
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What To Keep An Eye On
1. “Peak meat” vs “peak veganism.” The Dutch government is embarking on a $25 billion program to buy out animal farms near nature reserves, as part of an effort to reduce nitrogen and carbon pollution. But at the same time a slump in the sales and share prices of fake meat start-ups, some of whom tout a 90% smaller carbon footprint than beef, has sparked cries of “peak veganism.” Wired magazine concluded that the truth, as so often, is complicated.
2. Anti-waste tech. Edipeel is an edible, plant-based barrier applied as a very thin layer to fresh fruits and vegetables to slow down the decay process, the company claims, by a factor of two. Other researchers are developing coatings made from microbes, or even making tomato- or chocolate-flavored edible packets and food bags.
3. Government carrots. In America, the USDA just announced that its Conservation Reserve Program has distributed more than $1.75 billion to support sustainable farming, including carbon sequestration on farms. Europe is also considering whether to introduce a cap-and-trade system for carbon among its food producers, reports Politico, although some experts are skeptical whether the carbon price will be set high enough to spur real change.
