By Casey Frye, CCNN Writer
Over the past few years, there have been several studies that point out how human activities like driving and creating electricity increase the rates of greenhouse gases – gases that trap and hold heat in the atmosphere. According to a new report published in the Nature Climate Change journal, however, not enough attention is paid to how much global warming is caused by livestock like cows and sheep.
According to the study, the number of livestock who spend time ruminating (chewing on grass) has increased about 50% over the last 50 years. A different report showed that methane is the second highest greenhouse gas after CO2, and livestock contribute quite a bit from their digestive processes. Almost 25% of the Earth’s land is used as a grazing place for the animals, and yet another 30% of fertile land is needed to grow their food.
These numbers really do add up, and according to study co-author William Ripple, a professor at Oregon State University, it’s about time we start paying attention.
“Because the Earth’s climate may be near a tipping point to major climate change, multiple approaches are needed [to minimize this],” said Ripple. “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.”
It’s not necessarily about reducing the quantity of livestock roaming our planet, explains co-author Helmut Haberl of the Institute of Social Ecology, as much as it is about cutting human demand for the animals. For example, sheep and cattle produce 19 to 48 times more greenhouse gases than protein-rich plants such as beans, soy, and grains. “Reducing demand for ruminant products could help to achieve substantial greenhouse gas reductions in the near-term,” explained Haberl, “but implementation of demand changes represent a considerable political challenge.”