Global warming has been called humankind’s “greatest challenge” and the world’s most grave environmental threat. The scientific community says that there is no doubt that global warming is real and that humans are largely to blame. Human activities are emitting vast amounts of “greenhouse gases” that prevent heat from escaping from the Earth’s atmosphere. Scientists report that this phenomenon will increasingly lead to catastrophic natural disasters, such as more frequent and intense droughts, floods, and hurricanes; rising sea levels; and more disease outbreaks. Scientists also warn that global warming threatens the lives of millions of humans and countless other animals. Many conscientious people are trying to help reduce global warming by driving more fuel-efficient cars and using energy-saving light bulbs. Although this helps, science shows that going vegetarian is perhaps the most effective way to fight global warming.
In a groundbreaking 2006 report, the United Nations (U.N.) said that raising animals for food generates more greenhouse gases than all the cars and trucks in the world combined. Senior U.N. Food and Agriculture Organization official Henning Steinfeld reported that the meat industry is “one of the most significant contributors to today’s most serious environmental problems.”
Carbon dioxide, methane, and nitrous oxide together cause the vast majority of global warming. Raising animals for food is one of the largest sources of carbon dioxide and the single largest source of both methane and nitrous oxide emissions.
Carbon Dioxide: The burning of fossil fuels (such as oil and gasoline) releases carbon dioxide, the primary gas responsible for global warming. Producing one calorie of animal protein requires more than 10 times as much fossil fuel input—releasing more than 10 times as much carbon dioxide—than does a calorie of plant protein.3 Feeding massive amounts of grain and water to farmed animals and then killing them and processing, transporting, and storing their flesh is extremely energy-intensive. In addition, enormous amounts of carbon dioxide stored in trees are released during the destruction of vast acres of forest to provide pastureland and to grow crops for farmed animals. On top of this, animal manure also releases large quantities of carbon dioxide.
You could exchange your “regular” car for a hybrid Toyota Prius and, by doing so, prevent about 1 ton of carbon dioxide from entering the atmosphere each year, but according to the University of Chicago, being vegan is more effective in the fight against global warming; a vegan prevents approximately 1.5 fewer tons of carbon dioxide from entering the atmosphere each year than a meat-eater does. The math is simple: You could spend more than $20,000 on a Prius and still emit 50 percent more carbon dioxide than you would if you just gave up eating meat and other animal products.
Methane: The billions of chickens, turkeys, pigs, and cows who are crammed into factory farms each year in the U.S. produce enormous amounts of methane, both during digestion and from the acres of cesspools filled with feces that they excrete. Scientists report that every pound of methane is more than 20 times as effective as carbon dioxide is at trapping heat in our atmosphere. The Environmental Protection Agency shows that animal agriculture is the single largest source of methane emissions in the U.S.
Nitrous Oxide: Nitrous oxide is about 300 times more potent as a global warming gas than carbon dioxide. According to the U.N., the meat, egg, and dairy industries account for a staggering 65 percent of worldwide nitrous oxide emissions.