- About 10 billion land animals in the United States are raised for dairy, meat and eggs each year.
- Factory farming accounts for 37 percent of methane (CH4) emissions. Methane has more than 20 times the global warming potential of CO2.
- The U.S. Environmental Protection Agency (EPA) estimates that confined animals generate three times more raw waste than humans in the United States.
- The animal waste is often over-applied causing dangerous levels of phosphorus and nitrogen in the water supply. In such excessive amounts, nitrogen robs water of oxygen and destroys aquatic life.
- The use of fossil fuels on farms to grow feed and to intensively raise land animals for food emits 90 million tons of CO2 worldwide every year.
- Globally, deforestation for animal grazing and feed crops is estimated to emit 2.4 billion tons of CO2 every year.
- Growing corn requires more nitrogen fertilizer than any other crop, and more than half the corn in the world is fed to animals.
- Manure in waste lagoons also contains salt and heavy metals which end up in bodies of water, in sediment, and move up the food chain.
- Factory farms contribute to air pollution by releasing compounds such as hydrogen sulfide, ammonia, and methane.
- According to a study done by the Environmental Integrity Project, some factory farm test sites in the U.S. registered pollution emission levels well above Clean Air Act health-based limits.
- The waste lagoons on Concentrated Animal Feeding Operations (CAFOs) not only pollute our groundwater, but deplete it as well. Many of the farms use the groundwater for cleaning, cooling, and drinking.
Switch to organic foods to save yourself and the environment. GO 
Sources: The Impact of Animal Agriculture on Global Warming and Climate Change , Climate Change and Animal Agriculture , Greenhouse Gas Emissions From Animal Agriculture , Environmental Integrity Project , NRDC