Reducing Gas Emissions from Livestock Key to Curbing Climate Change: Study

A study published recently in the journal Nature Climate Change highlights both the need for policy changes and greater emphasis on livestock management in order to curb climate change.

Although it's well known that significant quantities of methane are produced by the burps and excrement of the world's livestock, the study authors contend that inadequate attention is being paid to to the greenhouse gasses associated with ruminant animals such as cows, sheep, goats and buffalo.

"Because the Earth's climate may be near a tipping point to major climate change, multiple approaches are needed for mitigation," study leader William Ripple, a professor in the College of Forestry at Oregon State University. said in a statement. "We clearly need to reduce the burning of fossil fuels to cut CO2 emissions. But that addresses only part of the problem. We also need to reduce non-CO2 greenhouse gases to lessen the likelihood of us crossing this climatic threshold."

Ripple and his colleagues suggest that an effective way to mitigate the effects these greenhouse gasses have on the environment is to reduce global populations of ruminant livestock.

At approximately 3.6 billion heads, the world population of ruminant livestock is about half the global human population. Moreover, about 25 percent of the Earth's land area is dedicated to livestock grazing, and a third of all arable land is used to grow feed crops for livestock, the researchers write.

On the basis of pounds of food produced, cattle and sheep generate between 19 and 48 times more greenhouse gasses than protein-rich plant foods such as beans, grains, or soy products, the researchers found.

Based on their findings, Ripple and his colleagues suggest that a greater reduction in global warming could be achieved by eliminating methane produced by ruminants than by cutting CO2 emissions alone.

"Reducing demand for ruminant products could help to achieve substantial greenhouse gas reductions in the near-term," said study co-author Helmut Haberl of the Institute of Social Ecology in Austria, "but implementation of demand changes represent a considerable political challenge."

In the United States, beef consumption has dropped in recent years, but Americans, on average, still consume a tremendous amount of beef, an estimated 52 pounds per person in 2012, according to the Earth Policy Institute.

While beef consumption may continue to fall, it is unlikely that it will ever cease to exist as a custom, and there will continue to be a high demand for cattle, not only for beef but for dairy products as well.

But Ripple suggests that a series of policy changes that incentivize or otherwise dissuade people from eating beef could have some effect on the sum of emissions produced by livestock.

"On a large scale, motivating humans to change their diet to consume less meat would be challenging and unlikely to happen voluntarily without incentives," Ripple said in an email to Nature World News. "Employing a tax or emission trading scheme on livestock's greenhouse gas emissions would be one alternative that would modify consumer prices and affect consumption patterns."

Reducing the demand for, and thus the presence of ruminant livestock will be both a cultural and political hurdle, the researchers acknowledge. But they suggest that doing so will have benefits beyond curbing greenhouse gas emissions.

"Cutting the number of ruminant livestock could have additional benefits for food security, human health and environmental conservation involving water quality, wildlife habitat and biodiversity," said co-author Pete Smith of the University of Aberdeen in Scotland.

The researchers concluded that international climate negotiations such as the United Nations Framework Convention on Climate Change and the Kyoto Protocol do not pay enough attention to the gas emissions by ruminants, especially livestock in developing countries, which are among the fastest-growing ruminant producers.