Belching Cows and Endless Feedlots: Fixing Cattle’s Climate Issues

https://www.nytimes.com/2020/10/21/climate/beef-cattle-methane.html

Source: By Henry Fountain, The New York Times. 

Excerpt: HAPPY, Texas — Randy Shields looked out at a sea of cattle at the sprawling Wrangler Feedyard — 46,000 animals milling about in the dry Panhandle air.... ...at its most basic, the business simply takes something that people can’t eat, and converts it into something they can: beef. That’s possible because cattle have a multichambered stomach where microbes ferment grass and other tough fibrous vegetation, making it digestible. “The way I look at it, I’ve got 46,000 fermentation vats going out there,” Mr. Shields said. But this process, called enteric fermentation, also produces methane, a potent planet-warming gas that the cattle mostly belch into the air. ...Researchers within and outside the industry are working on ways to reduce emissions from fermentation, through feed supplements or dietary changes. ...In the United States, cattle are far from the largest source of greenhouse gases, which include carbon dioxide, methane and others. Their total contribution is dwarfed by the burning of fossil fuels for electricity, transportation and industry. But livestock are among the largest sources of methane, which can have 80 times the heat-trapping power of carbon dioxide although it persists for less time. ...cattle methane is part of a relatively short cycle. The methane results from eating vegetation that has grown by taking carbon dioxide from the atmosphere. After about a decade, the methane breaks down, forming carbon dioxide, which is used for more plant growth. In effect, the animals are recycling carbon over a short time frame, so if the cattle population remains roughly the same, the contribution to warming remains about the same. “It’s leaving the atmosphere as fast as it’s coming,” said Alan Rotz, a researcher with the U.S. Department of Agriculture who has studied emissions from beef production....