Imagine a vast American cornfield. You might imagine it all ends up as cobs piled high at farmers markets or stacks of tin cans at the grocery store, but the truth is far less quaint. Just under 10% of the crop is eaten by humans — and half of that is as high-fructose corn syrup, which isn’t exactly nutritious. A whopping 39% is used to feed livestock and 37% to produce ethanol for fuel. The remaining 14% is exported — some of that might get eaten, but a large chunk will be used for more animal feed or ethanol. Before we even get to pesticide use, water demand and the monocultures also associated with modern agriculture, we can see how much healthy produce is diverted from people’s plates.
This isn’t working for us. More than 820 million people lack sufficient food. Yet at the same time, obesity rates are rising, and many have nutrition-deficient diets. As a 2020 report from the EAT-Lancet Commission points out: Unhealthy diets now pose a greater risk of morbidity and mortality than unsafe sex, alcohol, drug and tobacco use combined.It’s also not working for the planet. Food production contributes about a third of global greenhouse gas emissions. Excessive use of pesticides, fertilizer runoff and land-use changes have helped facilitate catastrophic declines in biodiversity. Farming uses 70% of fresh water worldwide. As the global population continues to grow, output will have to expand just as extreme weather puts more pressure on agriculture. We’ve already seen how drought conditions have pushed the price of olive oil to record highs and exacerbated food shortages in the UK. Current projections suggest that, in a business-as-usual scenario, emissions from the global food system could rise between 50% to 80% by 2050 as it accommodates more hungry mouths.
Plenty of studies have explored how to reduce these emissions, but what if we were able to go a step further and create a food system that acts as a carbon sink rather than a source? A study, published in scientific journal PLOS Climate, suggests that it’s possible. As one of the only sectors with the potential to reach net negative emissions, we ought not squander the chance.
The research explores how several elements might combine to reduce emissions and sequester carbon from the atmosphere:
- The adoption of a healthy, flexitarian diet, defined as the EAT-Lancet diet, consisting mostly of plant-based foods with small amounts of animal protein. It equates to a portion of dairy a day, two portions of fish a week and either the equivalent of a hamburger’s-worth of red meat once a week or a chunky steak once a month — if you want it.
- The reduction of food waste by half. We currently lose or throw away a third of all food produced.
- Improving production efficiency to limit the amount of land needed. There’s a gap between the amount of produce agricultural areas can deliver and what’s produced. The study based its calculations on closing this gap by 2050.
- The implementation of novel technologies. These include things such as methane inhibitors to cut down on the amount of gas belched up by cows and enhanced rock weathering, in which pulverized rocks are spread over farmland to absorb atmospheric CO2, and agroforestry in which woodland is grown on land no longer needed for crops.
Diet shifts and waste reduction alone have been a big focus, and for good reason: They’re two of the most effective methods to lower your carbon footprint. If everyone were to adopt a predominantly plant-based diet and food loss were cut by 50%, food emissions would roughly halve. But these actions alone can’t completely decarbonize the industry. “That’s not really surprising,” explains Michael Clark, director of the Smith School’s sustainable food solutions program at the University of Oxford and co-author of the study. “If you’re producing something, that’s going to have emissions. The only way of having a fully net-zero food system is to not have a food system at all.” Hence, the importance of novel technologies.
Researchers explored many scenarios, from what would happen with 100% tech adoption and no other changes to the consequences of purely non-tech interventions. The results are hopeful: If 50% of humanity adopted a flexitarian diet, food loss was halved and the novel tech had a 50% adoption rate, then the food industry would remove 6.7 billion metric tons of CO2 equivalent (CO2e) a year. If everyone adopted a flexitarian diet, then that would nearly double to 12.4 billion metric tons of sequestered CO2e. That’s huge. In 2019, global aviation was approximately 920 million metric tons of CO2.
t’s important to note that this isn’t a sure thing. There are still large knowledge gaps to close and big challenges to overcome. Some of the technologies have only been tested in small-scale trials, leaving questions over their performance at the huge scales required. The study also didn’t factor in the economics and practicalities of adopting novel tech, which are likely to be high barriers. Any potential effects on water and biodiversity should also be researched.
We’ve already seen governments struggle to manage agricultural decarbonization. In the Netherlands, a new political party sprung up after farmers were outraged by government plans to pay them to close their farms in order to reduce nitrogen pollution. In Ireland, farmers have been pressured to cull cows. No doubt, herds will have to diminish — but fixing the problem must consider heritage and cultural concerns and offer farmers more than a payout.
Persuading people to shift their dining habits is also hitting a similar wall. The flexitarian diet is much healthier, and the authors of the EAT-Lancet report found that eating this way has the potential to reduce food-related mortality by about 11 million deaths a year. But while that might convince some, there’ll be entrenched habits and views to overcome as well. Clark explains: “You can wash your laundry with a different washing machine, or with solar energy as opposed to coal energy, but you’re still washing your laundry. Food isn’t viewed in the same way.” A vegetarian meal might give you the same macronutrients and calories than a meaty one, but they will be received differently based on people’s preferences.
Even cutting waste is a challenge. It’s easy to throw food in the bin. Any eco-friendly alternative must be just as cheap and easy or offer value beyond that. Divert Inc., a startup focused on converting squandered produce into energy, for example, has positioned itself as a full-on data product, designed to show stores the benefits of waste reduction methods such as price markdowns and help optimize supply chains to extend shelf life. It then aims to only convert food that can’t be donated into energy.
The report highlights something that’s emblematic of the wider climate fight: If we’re going to limit warming to below 2C above pre-industrial temperatures, preferably as close to 1.5C as possible, then it will take more than simply utilizing new technology, improving existing processes and adapting our behaviors: We need to take every angle of attack.