Clearing the air on greenhouse gases

Editor's note: The following article was written by

Bovine Veterinarian

Editor John Maday and published in the

June issue of

PORK Network

A cloud of misinformation continues to fog public perceptions toward the role of livestock in greenhouse gas (GHG) emissions, but Frank Mitloehner, a University of California- Davis professor and air-quality specialist, is working to clarify the issue.

Mitloehner recently published a white paper titled, "Livestock's Contributions to Climate Change: Facts and Fiction," that shows food animals are minor contributors to U.S. and global GHG emissions.

Unfortunately, the fiction permeating this issue continues to influence the public, and public policy, around the world.

Recent news out of Denmark indicates the government there is considering a tax levy on red meat to change eating habits and help reduce GHG emissions.

In proposing the tax, the Danish Council of Ethics said cattle accounted for around 10% of the CO2 released into the atmosphere, while food production makes up around another 20%. Here in the U.S., special-interest groups repeatedly claim that livestock account for up to 51% of all GHG emissions—as much as or more than the transportation and energy sectors.

In the white paper, Mitloehner notes that the U.S. Environmental Protection Agency (EPA) and leading scientists have quantified livestock as the source of just 4.2% of all U.S. GHG emissions.

The transportation and energy sectors, meanwhile, contribute 27% and 31% of U.S. GHG emissions, respectively, and 58% combined. According to EPA data, beef cattle contribute 2.2%, dairy cattle 1.37%, swine 0.47%, poultry 0.08% and sheep, goats and other livestock contribute 0.08% of GHG emissions. Livestock GHG emissions have declined over time in the U.S., largely because of amazing improvements in production efficiency, and that trend continues.

Activists are happy to tell you that eating a hamburger is equivalent to driving a Hummer, and that observing "Meatless Mondays" can save the world. Mitloehner's figures show that if all Americans adopted Meatless Mondays, the reduction in U.S. GHG emissions would total 0.6%.

In contrast, if Americans replaced incandescent lightbulbs with Energy Star-rated bulbs, the reduction in GHG emissions would be 1.2%, twice that of abstaining from meat.

"One certainly cannot neglect emissions from the livestock sector," Mitloehner says, "but to compare them to the main emission sources would put us on a wrong path to solutions, namely to significantly reduce our anthropogenic carbon footprint to reduce climate change."