Global meat consumption has increased significantly in recent decades, with per capita consumption almost doubling since the early 1960s, according to the Food and Agriculture Organization of the United Nations (FAO). Whereas an average of 23.1 kilograms (50.8 pounds) of meat per person were consumed annually in the '60s, the figure had risen to 43.2 kilograms in 2019. Studies show that wealthier countries tend to consume more meat. Projections show that global per capita meat consumption will climb to 69.5 kilograms in 2022 — but the figure will be 27.6 kilograms in the developing world.

Greenhouse gases, livestock

According to FAO data, 14.5 percent of all human-caused greenhouse gas emissions are attributable to livestock farming, an industry that emits not only carbon dioxide (CO2), but also methane (CH4) and nitrous oxide (N2O) — two gases considered to play a similar role to CO2 in driving global warming. Though methane and nitrous oxide do not remain in the atmosphere as long as CO2, their respective climate warming potential is about 25 times and 300 times higher than that of carbon dioxide. To compare the impact of different greenhouse gases, a carbon dioxide equivalent (CO2eq) is typically calculated.

Most emissions in livestock farming result from feed production (58 percent) and are released during animals' digestive processes (31 percent); ruminants such as cattle, sheep and goats produce large quantities of methane. Processing and transport account for sizable share of greenhouse gas emissions (7 percent), as well, as does the storage of manure (4 percent). About 87 percent of methane and nitrous oxide emissions in livestock farming are attributable to cattle farming because of the sheer number of animals.

These figures pertain to overall livestock farming, meaning that they also encompass areas such as dairy farming, cheese, gelatin and wool production. A large percentage of methane emissions, for example, is linked to dairy cows.

It can be concluded that about 15 percent of global greenhouse emissions result from livestock farming — almost on par with those produced by the transport sector.

Avoiding meat to slow global warming?

Examining greenhouse gas emissions tied to livestock farming does not tell us everything about the impact of meat consumption on the climate. As such, comparing greenhouse gas emission from plant-based and animal-based foods is more insightful. A 2021 study published in Nature Food did just this.

It found that that plant-based foods account for just 29 percent of greenhouse gasses emitted by the global food industry. In contrast, 57 percent of greenhouse gas emission in the industry are linked to breeding and rearing cows, pigs and other livestock, as well as producing feed. A quarter of global greenhouse gas emissions in the food industry are said to result from beef production alone. This is followed by rice cultivation, which generates more greenhouse gases than pork, poultry, lamb, mutton and dairy production.

The study analyzes total global greenhouse gas emissions for each food product. A more nuanced pictures emerges when one studies the environmental impact in producing just 1 kilogram of the different foods. With 99.48 kilograms of carbon dioxide equivalents per kilogram, beef production remains the biggest source of greenhouse gases. This is almost double the carbon dioxide equivalents per kilogram linked to lamb and mutton production (39.72 kilograms).

Pork and poultry production show lower carbon dioxide equivalents, at 12.31 kilograms and 9.87 per kilogram of meat, respectively. Both also emit fewer emissions than cheese production (23.88 kilograms) and fish farming (13.63 kilograms). This means that greenhouse gas emissions vary considerably depending on the kind of meat produced and consumed. Switching from eating beef to consuming poultry, for example, already result in fewer greenhouse gas emissions. Today, an average 9 kilograms of beef are consumed every day, resulting in 0.8 tons of carbon dioxide equivalents. If Europeans and North Americans were to forgo eating beef, they would cut 1.2 tons and 3.3 tons of carbon dioxide equivalents, respectively.

Most greenhouse gas emissions from plant-based foods are lower than those linked to animal-based foods. Take the example of rice. Producing one kilogram of the food staple results in 4.45 kilograms of carbon dioxide equivalents — less than half the emissions released when producing one kilogram of poultry. Forgoing meat entirely, therefore, can help reduce your carbon footprint considerably. Meat consumption is linked to an annual carbon dioxide equivalent of 1.1 tons on global average. In Europe, meat accounts for an average 1.8 tons carbon dioxide equivalents, and a staggering 4.1 carbon dioxide equivalents in North America — that's statistically the amount of greenhouse gas emission a person living in India produces over the course of two years and four months.

For context: To become carbon neutral by 2050, every person on the planet would need to cut their emissions to an annual 2 tons of carbon dioxide equivalents, or less — roughly the amount attributable to European meat eaters.

Choosing not to consume beef, lamb and mutton could have additional benefits. These industries, after all, require 116 times the land needed to cultivate rice. According to a recent United Nations Environment Programme (UNEP) study, animal farming accounts for 78 percent of agricultural land worldwide. Yet expanding agricultural and pastureland leads to habitat destruction. The use of pesticides further exacerbates biodiversity loss.

Verdict

The meat industry is responsible for a large share of global greenhouse gas emissions. It contributes not only to global warming but also causes direct environmental pollution. People who eat a lot of meat can help fight the climate crisis by reducing or quitting meat consumption altogether. Even substituting other meat for beef would considerably reduce greenhouse gas emission.

What can you do?

Typical Europeans and North Americans could cut back one-quarter of their annual average greenhouse gas emissions if they switch to plant-based foods. That said, other areas of life are a bigger source of greenhouse gases — for instance the transport and aviation sector. Driving 10,000 kilometers (6,000 miles) a year causes over 2 tons in CO2 equivalents, as does a round-trip flight from Europe to New York. That figure doubles when you fly from Europe to Asia or South America.