Sonoma State University
hands holding a small earth globe

Sustainability at Sonoma State

Pledge Category 1: Diet

Reducing Reliance on Animal Agriculture

Approximately one third of the land’s surface is used for either direct livestock production or feed for livestock [1]. Without significant shifts, dietary greenhouse gasses alone in 2070 could exceed the total greenhouse gas budget imposed by the 2°C climate warming target. [2, 3].

Shifting diets to deal with climate change, human health, biodiversity, species extinction, ocean pollution, and water use is a simple step that requires no government intervention. Reducing reliance on animal agriculture could change what is now a major source of greenhouse gas emissions (the animal agriculture sector) to a major sink of greenhouse gas emissions. There is no other sector of the economy for which this is true.

Take the Pledge!

More Diet Information

There are efforts, many local, to reduce the effects of animal agriculture (e.g., The Marin Carbon Project). They have made some advances in reducing the impact of animals on the environment. However, the impact of animals on the ecosystems of both the land and the oceans is still considerable. In addition, this pledge is designed with students in mind - students that will graduate, leave the university, and migrate to areas without such projects available.

One argument that proponents of local animal farming often make is that local animal agriculture only contributes a few percent to the total local greenhouse gas emissions. For example, the 2018 Sonoma County Greenhouse Gas Assessment concludes that livestock emissions and fertilizer use contribute 11% to the greenhouse gas emissions of Sonoma County [4]. However, such assessments generally ignore the reality that almost all of the meat consumed is imported from outside of the county, with a correspondingly high climate footprint that is not accounted for.

The ecological impact of animal farming includes both meat and dairy farming. Both rely on extensive resource use, contribute to greenhouse gas production (including methane), and impact nearby communities. In terms of dairy production, the State of California and local Sonoma County dairies have promoted the development of methane digesters. These digesters help reduce the amount of methane released into the atmosphere by livestock. They are also actively conducting research to reduce the amount of methane released by cows through diet modifications. However, these efforts at sustainability, even if ultimately somewhat successful, do not in themselves address some of the larger land use and resource use issues associated with industrialized animal agriculture.

The oceans are directly affected by these land based animal operations through their effects on climate. In addition, the (sometimes) inadvertent release of manure and fertilizer from feed crops helps to create oceanic “dead zones” - large regions without oxygen and therefore without life [5]. In addition, the oceans are overfished, with 90% of fish stocks at or above sustainable capacity, with this trend toward unsustainability increasing [e.g., 6]. The amount of bycatch is incredible, with estimates generally ranging from 10-20%, although this estimate varies widely by species and fishery [e.g., 7]. Some bycatch estimates for some fisheries indicate that bycatch can be five pounds per single pound of caught fish. The simplest way to save imperiled species that are caught as “bycatch”, such as sharks, is to stop eating fish.

We have deliberately not emphasized “food miles” and the “buy local” movement in the pledge. Although buying locally does help to build stronger communities, and provide for a more robust economy, the actual contribution of “food miles” toward the total climate impact of a given food item is very low. For example, the food miles contribute just a couple of percent, on average, to the greenhouse gas footprint of beef. Even with transportation factored in, beef is associated with a greenhouse gas climate cost of 50-200 times that of fruits and vegetables [8,9].

Finally, if you are not at the point in your life where you can commit to being fully vegetarian or vegan, we do encourage you to think about purchasing your meat and/or dairy from local, sustainably sourced providers that are trying to make a difference. This can begin to help address some sustainability issues, and it does help support local members of the community.

Take the Pledge!

Brief Diet / Agriculture Notes

“A [“plant based”] diet is probably the single biggest way to reduce your impact on planet Earth, not just greenhouse gasses, but global acidification, eutrophication, land use and water use.” (Joseph Poore, University of Oxford) [10]

Meat, dairy, and fish farming currently use 83% of farmland worldwide. This environmental footprint could be reduced by 75% if the population of the world stopped eating meat. [e.g., 11]. This reduction would obviously help with greenhouse gas reduction, species extinction, erosion control, reduction in antibiotic use, reduction in water use, and habitat restoration.

Worldwide, shifting to a plant based diet by 2050 (rewilding 75% of the land allocated to meat production) would lead to massive sequestration of CO2. This shift alone would provide half of the greenhouse gas reduction necessary to limit warming to 2°C [12].

In the United States, simply shifting from beef to beans could help the United States achieve between 46 and 74% of the GHG (Greenhouse Gas) Reductions Necessary To Meet the 2020 Climate Accords.[13]

Factory farms (Concentrated Animal Feeding Operations, CAFOs) often try to contain animal waste in large lagoons. In addition to being impacted by the effects of pollution when the lagoon leaks, communities living near these operations often suffer from the lagoons releasing airborne particulates, leading to inflammatory, immune, irritation, and neurochemical issues. [14]

In the United States, CAFOs supply approximately 99% of the animals that people consume [15].

Roughly 5% of water use in the United States is for household use. Approximately 55% is allocated to livestock. [16]. While these figures can vary depending on the year and the method used to determine the percentages, in a very real sense, water crises can often be thought of as livestock crises.

Detailed modeling efforts suggest if people worldwide adopted a vegetarian diet, premature deaths could decrease by 7.3 million deaths annually. Adopting a plant based diet could lead to a reduction of 8.1 million premature deaths annually. The associated health care savings are significant and vary by region. [17]

Detailed estimates suggest that only one in ten large predator fish (tuna, sharks) remains since the start of large factory fishing. [18]

Dairy ranching at Point Reyes remains controversial, with environmental advocates insisting that fecal contamination is not being monitored correctly, with associated environmental impacts. [19,20]

Take the Pledge!

Diet Resources

Diet Further Reading / Watching

  • General Information About Animal Farming: Book: Eating Animals, by Jonathan Safran Foer, 2009. A personal journey into the subject, providing a good overview of ethical and environmental considerations. ISBN-10 0316069906
  • General Information About the Global Meat Industry: Annual Report: Meat Atlas: General Facts and Figures About the Animals We Eat, Heinrich Boll Stiftung.
  • General Information about Livestock Issues: Food and Agriculture Organization of the United Nations (2006), Livestock’s Long Shadow: Environmental Issues and Options, ISBN 978-92-5-1055-71-7.
  • A Summary of the Largest Diet Study to Date: Book: The China Study: The Most Comprehensive Study of Nutrition Ever Conducted and the Startling Implications for Diet, Weight Loss, and Long-Term Health, by T. Colin Campbell and T. M. Campbell II, 2004. ISBN-10 1932100660
  • General Information about Health in Athletes: Film: The Game Changers.
  • General Information about Health in People: Film: Forks Over Knives.
  • General Information About Livestock Production: Film: Cowspiracy. Note: The industry has some issues with potential exaggerations in this film. However, the film also contains a good deal of information.
  • General Information About the Health of the Oceans: Film: Mission Blue (featuring Dr. Sylvia Earle).
  • General Information About Viewing Sea Creature as Individuals: (This category was included based on a comment made by Dr. Earle in an interview, as she was hoping that people could learn about sea creatures as individuals rather than viewing them simply as livestock to be harvested): Film: My Octopus Teacher.
  • Good Climate Reporting: The Guardian

Take the Pledge!

Diet Footnotes

[1] Food and Agriculture Organization of the United Nations (2006), Livestock’s Long Shadow: Environmental Issues and Options, ISBN 978-92-5-1055-71-7.

[2] Harwatt, H., J. Sabate’, G. Eshel, S. Soret, W. Ripple (2017), Substituting beans for beef as a contribution toward US climate change targets, Climatic Change 143:261–270, doi: 10.1007/s10584-017-1969-1.

[3] Hedenus, F., S. Wirsenius, and D.J.A. Johannson (2014), The importance of reduced meat and dairy consumption for meeting stringent climate change targets, Climatic Change (124): 79-91,

[4] Regional Climate Protection Authority (2020), Sonoma County Greenhouse Gas Inventory: 2018 Update.

[5] Food and Agriculture Organization of the United Nations (2006), Livestock’s Long Shadow: Environmental Issues and Options, ISBN 978-92-5-1055-71-7.

[6] Food and Agriculture Organization of the United Nations (2020), The State of World Fisheries and Aquaculture 2020.

[7] Food and Agriculture Organization of the United Nations (2015), A Third Assessment of Global Fisheries Discards.

[8] Poore, J., and T. Nemecek (2018), Reducing food’s environmental impacts through producers and consumers, Science, 01 Jun 2018:, DOI: 10.1126/science.aaq0216.

[9] Our World In Data, (accessed April 2010), based on Poore and Nemecek (2018).

[10] Carrington, D. (May 2018), Avoiding meat and dairy is ‘single biggest way’ to reduce your impact on Earth, Guardian, U.S. Edition.

[11] Ritchie, Hana (2021), If The World Adopted a Plant Based Diet, We Would Reduce Global Agricultural Land Use from 4 to 1 Billion Hectares, Our World In Data.

[12] Eisen, M.B. and Brown, P.O. (2022) Rapid global phaseout of animal agriculture has the potential to stabilize greenhouse gas levels for 30 years and offset 68 percent of the CO2 emissions this century, PLOS Clim 1(2): e 0000010.

[13] Harwatt, H., J. Sabate’, G. Eshel, S. Soret, W. Ripple (2017), Substituting beans for beef as a contribution toward US climate change targets, Climatic Change 143:261–270, doi: 10.1007/s10584-017-1969-1.

[14] California Senate (2004), Confined Animal Facilities in California.

[15] Foer, J.S., (2009), Eating Animals, page 12.

[16] Jacobson, Michael F., (2006), Six Arguments For a Greener Diet: How a More Plant-based Diet Could Save Your Health and the Environment. Chapter 4: More and Cleaner Water, . Washington, DC: Center for Science in the Public Interest.

[17] Springmann M, Godfray HCJ, Rayner M, Scarborough P (2016). Analysis and valuation of the health and climate change cobenefits of dietary change. Proc Natl Acad Sci.

[18] Myers, R.A., and B. Worm (2005). Extinction, survival or recovery of large predatory fishes, Phil. Trans. R. Soc. B36013-20.

[19] Center for Biological Diversity (2017), Cattle Waste Puts California's Point Reyes on 'Crappiest Places in America' List.

[20] Bohemian (2021), Marin County Posts, Then Removes, Fecal Bacteria Warning Signs at Point Reyes Beaches.

Take the Pledge!