Getting energy out of grass is just not straightforward. That’s why cows and different ruminants, like goats and sheep, have a number of compartments of their stomachs to assist them digest their meals. A kind of stomachs is populated by microbes that assist break down plant matter right into a extra digestible kind. The method, known as enteric fermentation, additionally produces methane, a potent greenhouse fuel that’s 80 occasions extra environment friendly at heating the ambiance than carbon dioxide over the primary 20 years it’s within the ambiance, earlier than it breaks down into different compounds. A single cow releases round 250-500 liters of methane a day. There are roughly 1 billion cows used within the international meat and dairy industries, and, mixed with different animals raised for livestock, are answerable for releasing the methane equal of some 3.1 gigatons of carbon dioxide into the ambiance yearly. If cows had been a rustic, they might be the world’s third-largest greenhouse-gas emitter, behind China and the U.S., and forward of India.
On the COP26 local weather convention held in Glasgow final week, greater than 105 nations pledged to scale back methane emissions by 30% by 2030. Most international locations’ pledges targeted on tamping down on their oil, fuel and coal industries, that are answerable for a 3rd of human-caused methane emissions—only some plans targeted on tackling agricultural sources of methane, which contribute 42% of the worldwide whole of the greenhouse fuel.
Learn extra: A Methane Pledge Is the First Good Information Out of COP26. Nothing Else Will Be as Simple
The Intergovernmental Panel on Local weather Change, the United Nations’ premier local weather physique, recommends that people devour much less meat and dairy as a method to scale back international warming. However getting people to alter their consuming patterns is tough. Tackling the problem at its supply—on this case, the cows themselves, may very well be far simpler.
Scientists have developed a number of approaches for capturing bovine emissions, from masks fitted for cow noses that limit the quantity of methane the animals’ burps launch into the ambiance to ingenious, however misguided, plastic backpacks designed to lure cow farts. (For what it’s price, many of the methane produced by cows is launched by belching, solely 5% comes out of the opposite finish). Farmers are selectively breeding lower-emitting cows, and a few veterinary scientists are engaged on a vaccine that targets the methane-emitting micro organism in cow guts whereas leaving extra useful (and fewer polluting) microbes alone.
The perfect options, nevertheless, begin on the supply, with feed components. In September Brazil and Chile authorized the usage of Bovaer, an artificial feed complement developed by Dutch bioscience firm DSM that reduces methane emissions in dairy cows by 30%, and as much as 80% in beef cattle. However the complement is an added value for farmers, and except there may be an incentive—both by authorities rules, subsidies or market demand—its use is just not prone to be widespread.
Agriculture scientists are additionally searching for cheaper and simpler pure options. They could have found it in an ingredient hardly ever discovered close to cow pastures: seaweed.
In 2020 Australian researchers discovered that changing 3% of a cow’s eating regimen with a kind of seaweed native to Australia resulted in as much as an 80% lower in methane emissions. Now researchers in Eire and the UK are looking for out if their native variant does the identical. Scientists on the Institute for World Meals Safety at Queen’s College Belfast are launching a €2 million venture to observe the consequences of feeding native seaweed to dairy cows. Sharon Huws, a professor of animal science and microbiology, and lead scientist on the venture, says she expects to see not less than a 30% discount in methane emissions, and hopes to see extra.
“Utilizing seaweed is a pure, sustainable approach of lowering emissions and has nice potential to be scaled up,” say Huws. “There is no such thing as a cause why we are able to’t be farming seaweed.”
Learn extra: The Cow That Might Feed the Planet
Feeding cows seaweed might seem to be a drop within the bucket in comparison with the overwhelming influence of world greenhouse fuel emissions. Not so, says Sarah Ann Smith, director of the so-called “super-pollutants”(which means methane) program on the U.S.-based Clear Air Job Drive. Even chopping 30% of emissions from enteric fermentation would lead to an enormous discount in atmospheric methane, she says—about 11% of the full. That’s on par with the annual emissions produced by all international landfills—which make for a much more difficult supply to sort out. “The fact,” she says, “is that we’re at some extent on local weather change the place we now have to throw all this spaghetti on the wall and see what sticks.” Present projections present that meat consumption globally goes to rise, she factors out. “We don’t have the posh of choosing and selecting anymore, we’d like all of the options on the desk.”
Or, because the case could also be, within the feeding trough.