A billion head of cattle roam Earth – burping out methane

Cows, you see, have a serious emissions problem. To digest tough plant material, their cavernous stomachs act as fermentation vats. They’re teeming with methanogens, microbes that process cellulose to make volatile fatty acids, which the cows turn into meat and milk. But those methanogens also produce methane, a particularly nasty greenhouse gas that is 80 times more potent than carbon dioxide, thanks to the way its molecules vibrate to absorb infrared radiation. These gases capture heat, and that means more global warming…

Now multiply those burps by the world’s huge cattle population. To satisfy humanity’s bottomless appetite for beef and milk, a billion head of cattle now roam the planet. A paper published in September in the journal Nature Food by an international team of researchers found that the global food system generates a staggering 35 percent of total greenhouse gas emissions. Beef is responsible for a quarter of those food emissions, with another 8 percent coming from milk production…

If scientists can figure out how to get cows to stop belching so much, that would make a big dent in emissions, and we’d see the climate effects almost immediately. So Mitloehner and other researchers are experimenting with food additives like seaweed, garlic, and even essential oils derived from plants like coriander seed, which tweak the animals’ gut environment in different ways, for instance by disrupting the enzymes that produce methane.

RTFA. Lots about hows and whys of the difficulties coming up with a solution to the problem. Beaucoup detail about the inventive constructs researchers come up with to measure the methane output…and what they’ve tried, so far, in attempts to mitigate that production.

Research claims grazing doesn’t increase global warming

Argentine researchers are studying means of capturing cow methane

Grazing by cows or sheep can cut emissions of nitrous oxide — a powerful greenhouse gas — in grasslands from China to the United States, according to a study that overturns past belief that farm animals stoke releases.

Adding to understanding of links between agriculture and global warming, the report in…the journal Nature said livestock can help to limit microbes in the soil that generate the gas, also known as laughing gas.

“It’s been generally assumed that if you increase livestock numbers you get a rise in emissions of nitrous oxide. This is not the case,” said Klaus Butterbach-Bahl of the Karlsruhe Institute of Technology in Germany who was among the authors.

Laughing gas is one of several heat-trapping gases linked to farm animals and the scientists said there was a need for more study to see how far their findings would affect agriculture’s total impact on climate change.

Emissions of the gas account for 6-8 percent of global warming from human activities, making it the third most important greenhouse gas after carbon dioxide and methane, he said. Estimated nitrous oxide emissions from temperate grasslands account for 1-2 percent of the total…

Grasslands subject to winter frosts where such gas emissions may have been overestimated make up an area the size of India, or about a third of the world’s temperate grasslands that cover about 10 million square kms (3.9 million sq miles).

But the study did not look, for instance, at other damaging climate impacts of livestock. Goats, buffalo, cows and sheep also release heat-trapping methane as they digest food.

Ah-hah! They didn’t allow for methane which some researchers think could be collected for commercial use. No matter which end it comes from.