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We must listen to science — and act,” reads President Joe Biden’s January 27 Executive Order on climate change. For the farming sector, the latest greenhouse gas (GHG) inventory data from the Environmental Protection Agency (EPA) indicates that the U.S. needs to transition away from factory farm systems of meat and dairy production to reduce rising agriculture emissions.

The EPA’s inventory tracks GHGs from all sectors in the U.S. from 1990 to 2019, and conforms to reporting guidelines set by the United Framework Convention on Climate Change (UNFCCC). Setting emissions reduction goals and reporting progress is part of the Biden administration’s action to reenter the global Paris climate agreement.

Previously under the Paris Agreement, President Obama had pledged the U.S. would reduce emissions by 26-28% by 2025 from 2005 levels. The EPA inventory found that overall U.S. emissions are falling short of that pledge, declining only 12.9% from 2005 levels. The declines that have been achieved reflect “a continued shift from coal to less carbon intensive natural gas and renewables.”

While overall emissions are declining, agriculture-related emissions that take up nearly 10% of total U.S. emissions continue to rise. Most of agriculture’s emissions are linked to the potent GHGs methane and nitrous oxide. The EPA found that since 1990, agriculture-related methane emissions rose 17.5%, nitrous oxide emissions rose by 10.4% and carbon dioxide emissions rose 9.9%. Most of that increase can be attributed to the rapid growth over the last three decades of factory farms, particularly those raising cattle and hogs, and the immense amounts of concentrated manure they produce with associated methane and nitrous oxide emissions. These factory farms confine thousands of animals in tight quarters and produce massive manure lagoons. Ruminant animals like cattle are already a major source of agricultural methane emissions because of their unique digestive systems.

The EPA inventory likely undercounts the agriculture sector’s emissions. For example, the sector’s emissions linked to fuel for tractors or trucks, on-farm energy, some fertilizer production and farmland loss are all categorized within other chapters of the inventory. While the inventory does differentiate between feedlot and grazing and account for feed and geographic region, it doesn’t directly account for sustainably-managed grazing systems or organic systems that we know produce fewer emissions and can sequester carbon.

The EPA inventory indicates that the shift toward mega-dairies in the U.S. over the last several decades, with concentrated manure storage often linked to water and air pollution, may actually be increasing emissions per dairy cow. The EPA reports, “While emissions generally follow trends in cattle populations, over the long term there are exceptions. For example, while dairy cattle emissions increased 9.8 percent over the entire time series (since 1990), the population has declined by 3.1 percent.”

One explanation for an increase in emissions per dairy cow could be the loss of thousands of small and mid-sized dairies over the last decade due to consistent low prices. Whereas smaller and mid-sized dairies can more appropriately distribute manure on farmland, large-scale factory farms produce much more than can be applied on that farm or even in the surrounding area. Additionally, these mega-dairies, along with hog factory farms, are liquifying their manure, which the EPA associates with higher emissions.

The EPA found that methane emissions from manure management has risen 68% since 1990. The agency reports, “The majority of this increase is due to swine and dairy cow manure, where emissions increased 49 and 119 percent, respectively.” The EPA goes on to explain, “The shift toward larger dairy cattle and swine facilities since 1990 has translated into an increasing use of liquid manure management systems, which have higher potential CH4 (methane) emissions than dry systems.”

The factory farm system of handling manure also results in nitrous oxide (N20) emissions, both through the storage of manure in giant lagoons and through the application of that manure as it runs off fields into waterways. The EPA found that nitrous oxide emissions from manure management have increased 40% since 1990.

Agriculture-related emissions linked to synthetic fertilizer production and application are also rising — with much of the fertilizer applied to the corn, soybeans and other feed crops for animals within the factory farm system of production. The EPA reported N20 emissions related to agriculture soils, such as fertilizer use, had risen more than 9% since 1990. Many of the direct N20 emissions from cropland came from the Midwest corn belt, “where a large portion of the land is used for growing highly fertilized corn and N-fixing soybean crop,” wrote the EPA.

Emissions related to ammonia production and urea fertilization both have risen since 2005. The EPA reported that, “Carbon dioxide emissions (related to urea) have increased by 121 percent between 1990 and 2019 due to an increasing amount of urea that is applied to soils.”

GHG emissions and other air pollutants linked to factory farms have thus far largely avoided regulatory oversight. And GHG accounting aside, there is rising pressure to hold the industry to account. Water pollution linked to hog and dairy factory farms has been an ongoing challenge for rural communities across the U.S. from North Carolina to Wisconsin to Iowa. The factory farm system tied to agribusiness giants like Smithfield, JBS, Tyson and Cargill has flooded the market, driving out independent pork producers and small and mid-sized dairies.

Many of these highly polluting factory farms are often located in low income and communities of color. Rural residents in largely African American counties with clusters of hog operations owned or contracted to Smithfield in North Carolina have brought a series successful lawsuits charging the company with damaging their quality of life. Mega-dairies in California are located in the largely Latino communities facing air and water pollution in the San Joaquin Valley.

Rural advocates in Iowa and Oregon are pushing for a moratorium on new or expanding factory farms. Nationally, Senator Cory Booker introduced the Farm Systems Reform Act that would place a moratorium on new large-scale concentrated animal feeding operations (CAFOs), while funding a transition for farmers toward more regenerative systems of animal and dairy production. The Midwest-based Campaign for Family Farms and the Environment (which includes IATP) has called for a stop to subsidizing new and expanding factory farms through the Environmental Quality Incentives Program and government-backed farm loans.

In April, the Biden administration is expected to announce new emission reduction goals as part of reentering the Paris climate agreement. Biden’s Executive Order directs the USDA to solicit public input on how existing programs can support voluntary efforts in agriculture to protect the climate. But to reverse agriculture’s rising emissions documented in the EPA’s latest data, we will need to go beyond pledges and voluntary programs. We will have to appropriately regulate a factory farm industry that has thus far successfully externalized the costs of its water and air pollution to the rest of us.


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