Chapter 6 Agriculture

See index to all the chapters for Putting Out the Planetary Fire

Regenerative agriculture
– Project Drawdown on Agriculture
– Biochar
– Agriculture is Driving Deforestation
– Food Sovereignty

Chapter 6 Agriculture

Agriculture is often overlooked as a significant source of greenhouse gas emissions. Globally agriculture accounts for almost a third of emissions. That number is considerably less within the U.S., but we also export our emissions by importing a significant amount of our food, particularly livestock.

Our food system is also under threat from climate change and extreme weather, at both the level of production and distribution. The lack of access to healthy, affordable food for many is already a major domestic and global problem.

Only recently has the Intergovernmental Panel on Climate Change (IPCC) begun to highlight the role of agriculture in the climate crisis, including the recommendation to move to a more plant-based diet. This has become a focal point of attacks by opponents of climate action, who warn Americans that climate activists want to prohibit the sale of hamburgers at McDonalds, instead forcing people to eat insects[1] (yes, insects are already a food source in much of the rest of the world, especially Asia).[2]

There are far more fundamental reforms needed in our agriculture and food system than are addressed in this chapter. Americans may love family farms, but they have been replaced by giant corporate agribusiness dominated by factory farms, a heavy use of fossil fuels (pesticides, fertilizers), monocrops, assembly line production of animals, and genetic engineering.

One of my contributing editors, Liz Henderson, a policy coordinator for Northeast Organic Farm Association (NOFA-NY), observed that “no farm business comes anywhere near the size and power of the agribusinesses that are calling the shots. US agriculture is colonized by these concentrated megacorporations that supply chemicals, fertilizers, data control and buy, process, ship and sell what farms produce. It is time to regulate the biggest farm businesses (CAFOs) and stop pouring money into liquid manure management, synthetic nitrogen fertilizers and herbicides. Even more urgent is to dismantle corporate control with its cheap food policies and return to price supports, price limits, and supply management with mandatory conservation so that buyers pay farms the cost of production and the tax payers do not get stuck with the bill.”

One key movement is food sovereignty, “the right of peoples to healthy and culturally appropriate food produced through ecologically sound and sustainable methods, and their right to define their own food and agriculture systems.” La Via Campesina[3] is central to this effort. This “global peasant movement” unites people to fight injustice in the food system, including organizing for women’s rights and against land grabs and the spread of genetically modified organisms.


One of the greatest threats posed by climate change is its negative impact on our food system. Agriculture is also a major source of greenhouse gas emissions.

Rising temperatures, migrating pests, and changing rainfall patterns threaten our ability to raise and distribute enough food to feed the world’s current population. More than 10% of the world’s population remains undernourished, and food shortages could lead to an increase in cross-border migration, as the U.S. has seen following the prolonged drought in Central America. A particular danger is that food crises could develop on several continents at once. Food shortages are likely to affect poorer parts of the world far more than richer ones.[4]

It is estimated that global food production must increase by 60 to 100% to meet the expected rise in the world’s population by 2050. Global yields of maize and wheat, the world’s two most consumed crops, will decline significantly due to global warming in the coming decades.[5]

Climate change will disrupt food availability, reduce access to food, and affect food quality. Increases in temperatures, changes in precipitation patterns, increased extreme weather events, and reductions in water availability all threaten agricultural productivity. Climate change can also impact food distribution. For instance, in the U.S., the severe water shortages in 2012 impacted the Mississippi River, negatively including the distribution of grain and other food products in the mid-west. This also impacts the global food supply chain, reducing access and raising prices.[6]

Farmers are threatened both by flooding and drought. Flooding washes away fertile topsoil that farmers depend on and contaminates standing crops while droughts dry it out, making it more easily blown or washed away. Higher temperatures increase the water needs of crops. Some weeds, insects, and other pests benefit from higher temperatures and elevated CO2, increasing their ability to hurt crop production. Shifting climates enable some agricultural pests to migrate to new areas where farmers had not previously dealt with them and where they have no natural predators.[7]

The Environmental Protection Agency estimates that agriculture accounted for 11.2 percent of U.S. greenhouse gas emissions in 2020. Agricultural emissions include nitrogen (N2O) from cropped and grazed soils, the production of synthetic fertilizer from natural gas, methane (CH4) from enteric fermentation and rice cultivation, N2O and CH4 from managed livestock manure, and CO2 from on-farm energy use.[8] The impact of the U.S. food system overall, including food processing and disposal, as well as the global deforestation driven by American’s eating habits, is much greater. Transporting food across and between countries generates almost one-fifth of greenhouse gas emissions from the food sector – and affluent countries starting with the U.S. make a disproportionately large contribution.[9]

Large-scale and industrial agricultural operations generate high levels of greenhouse gas emissions – 29% of the world’s total. A UN report found that humans have degraded 40% of the Earth’s land surface, altering 70% of it. Four of the nine “planetary boundaries” – limits on how humans can safely use the planet’s resources – have been exceeded. Food systems are the largest culprit, accounting for 80% of deforestation, 29% of greenhouse gas emissions and the leading share of biodiversity loss. 70% of the world’s agricultural land is controlled by just 1% of farms, primarily large agribusinesses.[10]

The IPPC Special Report on Climate Change and Land noted that food supply per capita has increased more than 30% since 1961, accompanied by greater use of nitrogen fertilizers (an increase of about 800%) and water resources for irrigation (an increase of more than 100%). The food system is also under pressure from non-climate factors such as population and income growth and the demand for animal-sourced products. Fruit and vegetable production, a key part of healthy diets, will be negatively impacted by climate change. The IPCC has made recommendations to increase the productivity of land, waste less food, and persuade more people to shift their diets away from cattle and other types of meat to plants. Examples of healthy and sustainable diets are high in coarse grains, pulses (edible seeds from leguminous plants), fruits and vegetables, and nuts and seeds; and, low in energy-intensive animal-sourced and discretionary foods (such as sugary beverages). Supply-side options include increased soil organic matter and erosion control, improved cropland, livestock, grazing land management, and genetic improvements for tolerance to heat and drought. Diversification in the food system is a key way to reduce risks.[11]

As the Union of Concerned Scientists and others have pointed out, the dominance of corporate agriculture in the U.S. is part of the problem. Industrial agriculture treats the farm as a crop factory based on monocrops and assembly-line livestock operations rather than a diverse sustainable ecosystem. This lack of diversity creates risks for farmers while increasing climate impacts such as changes in crop viability and encroaching pests. The heavy use of toxic chemicals as pesticides and herbicides increases the pollution in downstream communities as flooding increases. Many farms will seek to increase irrigation in response to rising temperatures and drought, further depleting water supplies. Rising temperatures will expose farm workers to unsafe working conditions. One positive aspect of the recent federal climate budget bill (the Inflation Reduction Act) was that it increased funding for conservation programs to assist farmers in adopting sustainable practices to make farms more climate resilient.[12]

A December 2022 report, From Lab to Farm, highlighted the low priority of the federal government in reducing the climate impact of agriculture. It noted climate mitigation and adaptation is not a statutory priority of the U.S. Department of Agriculture (USDA). Federal agencies “spent an estimated $241 million per year on agricultural climate mitigation from 2017 to 2021. This amount is roughly 35-fold less than that spent on U.S. clean energy innovation.” The majority of funding went to soil carbon sequestration.[13]

Republicans, climate deniers and the fossil fuel industry have used the call to move to more plant-based diets as an attack point in the campaign to continue the burning of fossil fuels. Donald Trump and Texas Governor Greg Abbot falsely contended that President Biden’s climate plan would prohibit Americans from buying a McDonald’s hamburger. The issue of meat versus vegetarian diet dovetails with the ongoing culture war in America.[14]

Livestock production however, is the largest impact from agriculture, accounting for 14.5 percent of global GHG emissions from human activities. Meat from ruminant animals (have a digestive system utilizing four stomachs), such as cattle and goats, are particularly emissions intensive.[15] Livestock are also fed with corn and soy grown as monocrops produced with GMO seed, synthetic fertilizers and herbicides.

Regenerative Agriculture

Regenerative Agriculture uses farming and grazing practices to reverse climate change by rebuilding soil organic matter and restoring degraded soil biodiversity – resulting in both carbon drawdown and improving the water cycle. It seeks to rehabilitate the entire ecosystem placing a heavy premium on soil health with attention to water management, fertilizer use, and more. Such practices include compost application, cover crops, crop rotation, green manures, reduced tillage, organic production, diversified crops, and using beneficial plants to attract beneficial insects and pollinators. Rebuilding soil health is the keystone of enhancing agricultural climate resilience and combating climate change.[16]

The Climate Reality Project describes regenerative agriculture practices as follows:

Conservation tillage: Plowing and tillage dramatically erode soil and releases large amounts of carbon dioxide into the atmosphere. By adopting low- or no-till practices, farmers minimize physical disturbance of the soil, and over time increase levels of soil organic matter, creating healthier, more resilient environments for plants to thrive, as well as keeping carbon in the ground.

Diversity: Different plants release different carbohydrates (sugars) through their roots, and various microbes feed on these carbohydrates and return a variety of nutrients back to the plant and soil.

Rotation and cover crops: Left exposed to the elements, soil will erode and the nutrients necessary for successful plant growth will either dry out or wash away. Planting the same plants in the same location can lead to a buildup of some nutrients and a lack of others. By rotating crops and deploying cover crops strategically, farms and gardens can infuse soils with increased (and more diverse) soil organic matter, often while avoiding disease and pest problems naturally.

Mess with it less: In addition to minimizing plowing, regenerative agriculture practitioners are cautious about chemical or biological activities that can damage long-term soil health. Misapplication of fertilizers and other soil additives disrupt the natural relationship between microorganisms and plant roots. [17]

The federal government provides some support to regenerative agriculture and conservation methods, but the demand for funding exceeds the supply. Federal policy, however, also supports inherently unsustainable practices, such as concentrated feeding operations, which produce large amounts of waste that cause significant greenhouse gas emissions and can runoff into water resources.

Indigenous People in the Americas practiced regenerative agriculture long before Europeans came. For many hundreds of years, they practiced intercropping, based on  how the physical aspects of each plant complement one another and improve each other’s health and growth. For instance, the Haudenosaunee (Iroquois) in the Northeast used the Three Sisters. The corn stalks provide a natural trellis for the beans to grow on and beans help the corn grow by adding nitrogen to the soil. The squash vines acted as a “living mulch” that maintains soil moisture and prevents weeds from growing. Indigenous Americans practiced agroforestry, the management of trees, crops, and animals together in a way that benefits each.[18]

Project Drawdown on Agriculture[19]

Project Drawdown is a nonprofit organization started in 2014 that promotes creative solutions to help reduce and then draw down the levels of greenhouse gases in the atmosphere. Their ideas, drawn from leading scientists, often think outside of the box in developing solutions, such as the role of educating girls. Below are some of their approaches to agriculture.

Shift Agriculture Practices. Better agriculture practices can lower emissions from cropland and pastures, including methane generated by growing rice and raising ruminants, nitrous oxide emitted from manure and overusing fertilizers, and carbon dioxide released by disturbing soils.

Climate and meat. Shifting to a plant-based diet not only reduces emissions but growing animals for food is also inefficient. It takes about five to seven kilograms of grain to produce one kilogram of beef. Each of those takes energy and water to produce, process, and transport.

The problems with chemical agriculture. Synthetic pesticides and fertilizers are usually made from fossil fuels. Chemical farming uses more energy per unit of production than organic farms. Synthetic nitrogen fertilizers in soils produce nitrous oxide, a greenhouse gas about 300 times more powerful than carbon dioxide as a greenhouse gas. Organic farms rely on natural manure and compost for fertilizer. They store much more carbon in the soil.[20]

Food closer to home. The estimates of how far the average meal travels from the farm to plate range from 750 to 1500 miles. Food grown closer to home produces fewer transportation emissions, is fresher and supports local farmers. As the distance food travels decreases, so does the need for processing and refrigeration to reduce spoilage.[21] (However, some note that in terms of climate impact, what we eat and how it is grown can be more impactful than just being grown locally.)[22]

Silvopasture and Livestock. Silvopasture is an ancient practice that integrates trees and pasture into a single system for raising livestock. Silvopasture is significantly better than any grassland technique for reducing the methane emissions of livestock and sequestering carbon. Pastures strewn with trees sequester five to ten times as much carbon as those that are treeless. Project Drawdown notes that “The advantages of silvopasture are considerable, with financial benefits for farmers and ranchers. Livestock, trees, and any additional forestry products, such as nuts, fruit, and mushrooms, generate income on different time horizons. The health and productivity of both animals and the land improve. Because silvopasture systems are diversely productive and more resilient, farmers are better insulated from risk.” Silvopasture however often runs counter to farming norms and can be costly and slow to implement.[23]


Biochar is an issue where there is not yet consensus as to its overall benefits, though there are many who promote it as a climate solution.

Biochar, a charcoal-like substance made from burning organic materials in a low or zero-oxygen environment, can improve the quality of soil and trap carbon dioxide in the earth for potentially hundreds, or even thousands, of years. A recent study suggests that it could reduce irrigation costs for farmers, thanks to its highly porous and water-absorbent properties. However, it is costly and works better in some regions that others. Biofuels Watch, which has been critical in the past of biochar, states that “we are still very far from having a reliable understanding of biochar’s impacts – both the impacts on soils and plant growth resulting from application of biochar, and impacts from land use change to supply biomass for the production of biochar.”[24]

“Biochar benefits include decreasing soil acidity, retaining water and nutrients, removing unwanted contaminants, and providing a home for beneficial soil biology to thrive. Biochar is also known to persist in soil for millennia. Thousands of years ago, Amazons mixed biochar with their poor-quality soil to create terra preta (“black earth” in Portuguese), a soil product that is highly fertile to this day. Biochar has also been found in extremely fertile grassland soils called ‘Mollisols.”[25]

Agriculture is Driving Deforestation

Forests take up carbon dioxide from the atmosphere and release oxygen during photosynthesis. When forests are growing, photosynthesis exceeds respiration, and the surplus carbon is stored in tree trunks and roots and in the soil in what is known as sequestration. When forests are cut down, much of that stored carbon is released into the atmosphere again as CO2 as well as reducing the forest’s ability to sequester carbon. It is estimated that CO2 from tropical deforestation makes up around 10% of global warming pollution.[26]

A 2022 study found that logged tropical forests are a net source of carbon emissions for at least a decade afterwards. A prior study found that tropical forests are no longer carbon sinks as a result of deforestation and land degradation.[27]

Every year the world loses around 50,000 square kilometers of forest, 95% in the tropics. Agriculture is responsible for at least three-quarters of this – clearing forests to grow crops, raise livestock and produce products such as paper. The expansion of pastureland to raise cattle is responsible for 41% of tropical deforestation, with soy and palm oil accounting for another 20%.[28]

The planet’s largest areas of tropical forest are the Amazon basin in South America, the Congo Basin in Central Africa, and Southeast Asia. Amazonia has both the largest area of tropical forest and the highest rate of deforestation. Palm and other vegetable oils are the main drivers of deforestation in Southeast Asia; there are also large amounts of peaty soil, which releases CO2 when cleared. There have been some positive results for efforts to reduce the clearings – such as by recognizing indigenous groups’ sovereignty over their lands to civil society pressure on corporate deforesters to paying tropical countries that reduce their deforestation emissions, though unfortunately the Bolsonaro government in Brazil reversed much of the progress.[29]

In Amazonia, deforestation is killing Indigenous people who live in the forests for their survival. Forced from their forest homes, they are reduced from self-sufficiency to living on the sides of roads and/or depending on government handouts. The rates of disease, alcoholism, malnutrition, and suicide skyrocket. Similar problems are occurring in Indonesia due to palm oil. The forests there are home to about 50 to 70 million Indigenous people, about a quarter of the country’s population.[30]

Planting seedlings after clearing forests is not a climate solution for various reasons,[31] including that it takes decades before trees to grow enough to be major carbon sequesters.[32] Reforestation (the process of replanting an area with trees) and afforestation (the process of creating a forest on land not previously forested) are notorious for displacing communities, aggravating land conflicts, disrupting food systems, and diminishing biodiversity. Land belonging to local communities is appropriated, privatized, and organized by companies in the Global North, often disregarding local community ownership of such lands.[33]

Deforestation destroys ecosystems that are vital to wildlife, a factor in why the planet is amid the sixth great extinction of species.[34] When humans destroy their forest habitats, animals and insects seek shelter in nearby human communities. This unprecedented level of contact between humans and wildlife is dangerous because animals can spread pathogens to humans, which can lead to pandemics such as COVID (though that exact link has not been established).[35]

Food Sovereignty

Food sovereignty is the right of peoples to healthy and culturally appropriate food produced through ecologically sound and sustainable methods, and their right to define their own food and agriculture systems. People need to be able to decide what food they want to grow, not to have that decision dictated by corporate interests. Advancing food sovereignty would require major food system changes to create environmental stewardship, land ownership, and labor practices that build power and rights among farmers, food chain workers, and consumers.[36]

The Global Campaign for Climate Justice makes food sovereignty a key demand. A food sovereignty approach increases resilience to crises, helps mitigate the impacts of climate change, and ensures that people live in dignity and harmony with the environment. Their demands include: sustainable climate change resilient agriculture and agro-ecology; democratic access to land and land-based resources; the rights of small food producers; the recognition of women’s roles and rights in agriculture, aquaculture, fishing, and pastoral systems; farmers’ control of seed diversity; and the global re-organization of food production and trade towards prioritizing consumption of locally produced food.[37]