A comprehensive new study has quantified the greenhouse gas emissions from meat consumed in thousands of U.S. cities, revealing a “carbon hoofprint” equivalent to 329 million tons of carbon emissions annually. This figure is comparable to the yearly domestic emissions from fossil fuel combustion and exceeds the entire national carbon footprints of countries like Italy or the United Kingdom. The research, published in Nature Climate Change, analyzed data from 3,531 cities and found that the origin of the meat and the efficiency of its supply chain have a greater impact on emissions than the sheer volume consumed in a city.
The joint project between the University of Michigan and the University of Minnesota provides a first-of-its-kind systematic analysis of the sprawling supply chains for beef, pork, and chicken. Researchers discovered that factors in the production phase—such as the type of animal feed, the efficiency of farming practices, and manure management—are the dominant sources of emissions. Counterintuitively, a city’s per capita meat consumption was not a strong predictor of its per capita carbon hoofprint, shifting the focus from consumer demand alone to the intricate web of agricultural production that supports urban centers.
Deconstructing the Urban Hoofprint
The study introduces the term “carbon hoofprint” to represent the greenhouse gas emissions specifically associated with the production and transportation of meat destined for city dwellers. Annually, residents in the analyzed cities consume approximately 11 million tons of meat, a diet that comprises 4.6 million tons of chicken, 3.7 million tons of beef, and 2.7 million tons of pork. The emissions generated to produce this meat are substantial, highlighting the significant, and often overlooked, role of food systems in urban environmental impact assessments.
Traditionally, carbon accounting for cities has struggled to trace the impacts of consumption beyond municipal borders, often relying on broad national averages that obscure critical regional differences. This research created a high-resolution model to overcome that challenge, linking urban meat consumption directly to the rural counties that produce the animal feed, raise the livestock, and process the final meat products. According to Benjamin Goldstein, a lead author and assistant professor at the University of Michigan, this detailed mapping has “huge implications for how we gauge the environmental impact of cities” and develop more effective policies to reduce it.
Complex Supply Chains Drive Emissions
A central finding of the research is that the structure of the supply chain, not just transportation distances, dictates the size of a city’s hoofprint. The emissions embedded in meat are largely determined by how and where the animals are raised. Factors like the composition of fertilizer for feed crops, farm-level energy use, and methane released from livestock vary significantly across different agricultural regions of the country.
To illustrate this complexity, the study details the beef supply chain for Los Angeles. The city sources its processed beef from facilities located in 10 different counties. However, those processors get their livestock from animals raised across 469 counties, which in turn are nourished by feed crops grown in 828 distinct counties. This vast network demonstrates what the researchers call “urban-land teleconnections,” emphasizing that a city’s environmental impact extends far beyond its physical boundaries. While transportation is a piece of the puzzle, the researchers found its contribution to the overall hoofprint was not as significant as the emissions from the agricultural production stages.
Geographic Hotspots of Production and Consumption
The analysis revealed stark geographical differences in both meat consumption and its associated emissions. While major metropolitan areas like New York City, Los Angeles, and Chicago are the largest total consumers of meat, they do not have the highest per-person carbon hoofprints. In fact, the five cities with the highest per capita hoofprints were McAllen (Texas), Laredo (Texas), Corpus Christi (Texas), Oklahoma City (Oklahoma), and Fort Collins (Colorado). This disparity underscores that the emissions intensity of the meat supply chain is the critical variable.
The data also identified cities that defy simple assumptions. For example, 868 cities, including Milwaukee, Wisconsin, and Houghton, Michigan, recorded above-average per capita meat consumption while maintaining a below-average per capita carbon hoofprint. This occurs when a city sources its meat from relatively low-emission supply chains, where farming and processing are more carbon-efficient. These findings provide city-specific information that can empower local governments to understand their unique environmental connections and identify opportunities for change.
Pathways to Reducing Climate Impact
The study concludes that significant emissions reductions are achievable through targeted interventions. Researchers estimate that cities could lower their collective carbon hoofprint by 14% to 51% by implementing a combination of two key strategies: reducing food waste and shifting dietary patterns. Wasted food carries the full carbon cost of its production without providing any nutritional value, making its reduction a critical goal.
Furthermore, promoting dietary shifts away from meats with the largest environmental impact, particularly beef, offers a powerful tool for mitigation. The research suggests that replacing beef with chicken, which has a much lower carbon footprint, can lead to greenhouse gas savings comparable to major household investments like installing solar panels or performing energy-efficiency retrofits. These findings position dietary choice as a potent and accessible form of climate action for individuals and a viable policy lever for urban planners aiming to enhance sustainability.
Rethinking Urban Environmental Policy
This detailed mapping of the carbon hoofprint challenges cities to adopt a more holistic view of their environmental responsibilities. The data makes it clear that urban centers are deeply interconnected with rural agricultural systems, and effective climate policy must reflect this reality. The study provides the analytical foundation for cities to move beyond their borders and engage with the supply chains they depend on.
By quantifying the specific impacts of meat consumption for thousands of individual cities, the research provides an invaluable tool for creating targeted and effective environmental policies. It allows municipalities to understand their unique vulnerabilities and opportunities related to food systems. As cities nationwide grapple with ambitious climate goals, this work highlights that the dinner plate is a vital, yet often underappreciated, component in the broader strategy for achieving urban sustainability and reducing the nation’s overall greenhouse gas emissions.
