Reduce the Carbon Footprint
of the Livestock Industry
The livestock sector of agriculture plays a significant role in global warming. To elucidate this, the UN Food & Agriculture Organization (FAO) studied the whole meat production chain. They found that livestock are responsible for 18% of GHG emissions; a larger share than transport . Expanding pasture and feed crops accounts for 9% of carbon dioxide emissions. Over a third of methane emissions come from digestive fermentation by ruminant livestock. Animal manure contributes 65% of nitrous oxide. Livestock now make up a fifth of all terrestrial animal biomass. So the sheer quantity of animals raised for human consumption has come to threaten biodiversity. The Worldwide Fund for Nature states that a third of the Earth’s ecological regions are endangered by livestock production.
To mitigate global warming, the FAO  makes two recommendations. Firstly, livestock and feed crop production should be spatially intensified, to reduce deforestation. Secondly, animal nutrition and manure management should be improved to reduce methane and nitrous oxide emissions. The FAO says that consumers can exert the most effective political pressure on the industry.
Wordwide, 627 million tons of grain are devoted to livestock feed. Americans eat 25 times more meat per capita than Indians, thereby increasing their risk of cardiovascular disease and common cancers. Thus the 2nd expert report of the World Cancer Research Fund, Food, Nutrition, Physical Activity and the Prevention of Cancer: a Global Perspective  suggests limiting red meat consumption to no more than 18 ounces per week . By reducing meat consumption, we can protect biodiversity, mitigate global warming and gain the personal health benefits of a largely plant-based diet - all at the same time.
Well-known expert physician of integrative medicine Dr Andrew Weil has discussed the 'moral ferocity' and impacts on human health of eating meat from animals raised in contemporary factory farms . If we understood the nightmarish brutality of what goes on inside the windowless animal gaols and abbatoirs that produce 99% of U.S. meat, he states, we simply would not eat it. Corporations that run these operations take pains to conceal, behind a marketing imagery of chickens in nests and cattle in grassy pastures, extraordinary levels of cruelty, environmental destruction and dehumanization of workers.
Lord Nicholas Stern, former chief economist at the World Bank, is the foremost climate economist in the world. In an interview with The Times newspaper, he recently stated:"Meat is a wasteful use of water and creates a lot of greenhouse gases. It puts enormous pressure on the world's resources. A vegetarian diet is better." Direct emissions from cows and pigs produce methane, a greenhouse gas 23 times more powerful than carbon dioxide. A successful climate treaty, he states, would lead to soaring costs for meat and other foods that generate large quantities of greenhouse gas. And people's attitudes will evolve until meat-eating becomes unacceptable: "History shows that people change their notion of what is responsible...They will increasingly ask about the carbon content of their food." 
World Watch Magazine points out that livestock & their by-products account for 51% of annual worldwide greenhouse gas emissions - far above data reported by the FAO.
1. FAO  Livestock’s Long Shadow
2. WCRF  2nd Expert Report
3. Weil A.  The Moral Ferocity of Eating Animals
4. Stern N  in: Climate Chief Stern:Give Up Meat to Save the Planet