The United Nations Food & Agriculture Organization has issued a stunning report on global warming. Livestock production is responsible for more climate change gasses than all the motor vehicles in the world. In total, it is responsible for 18 percent of human induced greenhouse gas emissions. It is also a major source of land and water degradation.

Incredibly, 18 percent of global greenhouse gas emissions (as measured in carbon dioxide equivalent) are due to the growing numbers of livestock around the world. It's not just methane and manure -- land-use changes, especially deforestation to expand pastures and to create arable land for feed crops, is a big part. Emissions also arise from the energy used to produce fertilizers and pesticides for feed crops, run slaughterhouses, and pump water.

Livestock now use 30 percent of the earth’s entire land surface. In Latin America, 70 percent of former forests in the Amazon have been turned over to grazing. Animal waste accounts for 64 percent of ammonia, which contributes significantly to acid rain.

Livestock production is at the heart of almost every environmental catastrophe confronting the planet – rain forest destruction, spreading deserts, loss of fresh water, air and water pollution, acid rain and soil erosion.

Related: See our reports on climate change and meat production.