The link between livestock and climate change has never been clearer. Raising animals for food uses extraordinary amounts of water, causes deforestation and is a major contributor to greenhouse gas emissions, making the practice of raising animals seriously detrimental to the climate and to the overall health of the planet. Research suggests that a number of changes, including dietary changecan help reduce food-related climate emissions.
How does livestock farming affect climate change?
Raising animals on farms for food production has a huge impact on the health of the environment. Animal agriculture is a donor greenhouse gas emissions, including nitrous oxide and methane, water pollution, and the destruction of forests and other wilderness areas that help regulate the planet’s atmosphere.
How does livestock contribute to greenhouse gas emissions?
The two main greenhouse gases produced by the practice of farming animals are methane and nitrous oxide. Overall, raising animals for food contributes at least 16.5% greenhouse gas pollution.
Nitrous oxide is almost 300 times more powerful than carbon dioxide when measured on a 100-year global warming potential scale. A number of agricultural practices contribute to nitrous oxide pollution, including soil management practices such as applying synthetic and organic fertilizers to grow food for people and animals, handling manure from raising animals for food and burning crop residues. According to EPA figures, these practices account for 74% of all nitrous oxide emissions in the United States.
accounting for approximately 11 percent of all anthropogenic greenhouse gas emissions in the United States, methane has an impact 25 times greater than carbon dioxide. The agricultural sector is the largest source of methane emissions in the United States, according to EPA estimates.
Livestock Methane Emissions
Ruminants commonly raised for food, including cattle, goats and sheep, emit methane when they digest their food through a process known as enteric fermentation. During this process, microbes in the digestive tract of animals break down and ferment plant parts such as cellulose, starches, sugars and fibers. This process is incredibly efficient – ruminants like cows can eat plants and crop waste that humans cannot thanks to their larger stomach chamber called “rumen– but a by-product of this process is the toxic pollutant methane, released into the atmosphere mainly by animal burps.
Farmed methane manure is another source of emissions, particularly significant from concentrated animal feed, or CAFO, operations of hogs and dairy cattle that store manure in liquid form.
How does deforestation affect climate change?
Forests and other wild areas like savannas play an important role in store carbon that would otherwise be released into the atmosphere. Unfortunately, forests and other natural ecosystems around the world are being destroyed to make way for urban expansion, logging, mining and agriculture.
The largest forest in the world is the Amazon rainforest, which covers 2.72 million square miles and spans nine different countries. Considered one of the most important on Earth terrestrial carbon storesthe Amazon stores about 123 billion tons of carbon.
In addition to the role these ecosystems play in storing carbon, forests also stabilize floor with their roots, preventing erosion. When forests are destroyed, the soil itself is also able to hold less water, increasing the likelihood of flooding of nearby communities. Deforestation in some areas can also lead to an increased likelihood of drought as the water cycle is disrupted.
The biggest driver of deforestation in the Brazilian Amazon rainforest is animal agriculture, which has been linked to 75 percent loss of coverage. Loggers and farmers in the Amazon cut down trees to create ranches where cattle and other farm animals can live and graze, as well as to create fields of corn and soybeans to feed farm animals .
When forests are destroyed, whether by fire or converted to grow animal feed, carbon dioxide, once stored, is released into the atmosphere. Worse perhaps, these actions also rob the earth of its ability to store carbon, described by researchers as a ‘loss’opportunity cost” of climate action that can only be recouped if the land is reforested or reseeded.
How does meat consumption affect climate change?
Food-related greenhouse gas emissions of a variety of sources throughout the livestock supply chain. Sources include burps and manure from the animals themselves, storage of their manure, use of fertilizer on the fields used to raise them, fuel for transport, land used to feed and raise them, and heating and the machinery necessary for the production of animal agriculture.
Water use and pollution
Feed and raise animals as livestock use much more water than growing crops like soybeans or lentils. Beef production requires 15,415 liters per kilogram of meat, 112 liters per gram of protein and 153 liters per gram of fat. A third of all water used by the livestock sector is for beef production. Another 19 percent goes to dairy cattle for the production of milk and other dairy products.
Animal husbandry also pollutes waterways, disproportionate impacting Black and Indigenous communities, as well as other communities of color. This pollution comes mainly from manure pits or lagoons created to retain the droppings of the thousands of animals housed in factory farms. When pits leak or overflow, the nitrogen and other contaminants in the manure pollute local water sources, causing or exacerbating many health problems in surrounding communities. To avoid spillage, farmers often spread too much manure on fields, which also leads to polluting runoff.
How does climate change affect livestock?
The production of meat and other animal products is a major contributor to climate change, which in turn worsens the lives of millions of animals living in factory farms.
A central feature of industrialized agriculture is its efficiency, achieved by herding thousands of animals into a relatively small area to feed them for slaughter. The cramped quarters in which these animals live, associated with rising temperaturescauses metabolic disturbances, damage to cells in the body, and immune suppression, which in turn make disease, infection, and death more likely.
Why do some people say that beef production is only a small contributor to emissions?
Some proponents defend beef by pointing to the growing ability of the cattle industry to produce more meat from each cow slaughtered. Since the 1970s, the number of cattle needed to meet the demand for beef in the United States fell about 50 million.
The industry made this shift through intensive breeding that resulted in cows that grew faster and bigger than their parents and grandparents. The 90 million cattle that are raised to meet the demand for beef today, for example, provide more meat per animal than 140 million cattle in the 1970s.
Less livestock means less greenhouse gas emissions, but industry efficiency alone is not enough to meet the climate targets set in the Paris Climate Agreement to limit global warming. Climate research indicates the deployment of a number of strategies to reduce food-related emissions, including dietary changes in countries that currently consume the most beef. In the United States, for example, Americans eat four times more than the world average.
Another common argument made by camp members downplaying beef emissions is that cattle raised for beef only directly contribute to 3 percent greenhouse gas emissions in the United States. This percentage excludes climate impacts from land use, such as deforestation for grazing and growing animal feed.
Will eating less meat help reduce climate change?
Eating less meat is one of the most effective ways to reduce our personal or family contribution to climate change. In fact, plant-based foods have a carbon footprint 10 to 50 times smaller than animal products on average. Choose to eat vegetarian too decreases water consumption a third to a half compared to a diet that contains meat. Waste less food is another powerful form of household climate action.
Future action: Food system transition
Industrial animal farming is detrimental to ecosystems and communities, as well as to the health of the planet on which we all depend.
Food system change is a powerful and empowering form of climate action. To begin to move food systems away from their current central focus on animal protein, several advocacy groups are working with farmers to transition outside the livestock industry. An example is Transformation, an organization that works with poultry and pork producers to grow crops like mushrooms and hemp rather than raising animals for food. These efforts are only a small part of the much-needed collective transition to a more plant-rich food system.