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Methane emissions

Methane emissions: cows are part of the climate solution

Cows and cattle farming are always under attack, especially regarding methane emissions. But they can be part of the solution to the climate crisis.

Everyone is against cattle farms. Everyone is worried about their methane emissions. But are cows the real culprits when it comes to climate change? The answer is no. Far from being the problem, cattle farms could be part of the solution to the climate crisis. Although cow methane has a greenhouse effect 28 times greater than CO2 emitted from burning oil and coal, it remains in the atmosphere for only ten years, whereas carbon dioxide lasts centuries. So, it makes no sense to measure the environmental impact of farms in terms of CO2 equivalent.

Almost no one seems to accept the fact that #livestock is not the problem, but on the contrary could and should be part of the #ClimateSolution. Click To Tweet

Methane is a powerful climate-altering gas, but in addition to cows, it is produced by rice fields, swamps, landfills, even by the oceans and by the extraction of fossil fuels, whose emissions are even higher than expected: new research reveals that the impact of the extraction of fossil fuels (gas, coal and oil) and fugitive emissions accounts for 34% of anthropogenic methane. In comparison, methane from livestock farming accounts for 27% and landfills for 23%. The remaining share of methane of anthropogenic origin (16%) comes from other agricultural activities.

In the livestock sector, many steps forward have been made to reduce methane production through feed additives or anaerobic digesters. For example, a probiotic consisting of three strains of bacteria has been developed, which, when added to feed, can reduce methane by 68%, while another consisting of a single strain of microbial bacteria can achieve a reduction of 78%. There is also a supplement based on a red alga that can reduce the methane produced in the rumen of cows fed with this supplement by up to 92% without affecting their health, the taste of meat or the production or quality of milk and cheese.

Thanks to #zootechnics, a drastic reduction in #GlobalWarming can be achieved. But it is important to start evaluating and measuring its sources correctly. Click To Tweet

Thanks to animal husbandry, you can drastically reduce global warming. “If your question is: can we reduce global warming? The answer is yes, but we have miscalculated the contribution of methane,” Frank Mitloehner, professor and air quality specialist at the UC Davis Department of Animal Science, in this interesting video: “If we want to know what the impact of reducing methane is on warming, the equivalence to the unit of CO2 is completely wrong.”

In addition to remaining in the atmosphere for only a few years compared to CO2, making it a short-lived greenhouse gas, methane produced by cows is part of the biogenic carbon cycle. In practice, plants capture carbon dioxide from the atmosphere through photosynthesis, absorbing carbon and releasing oxygen; this carbon is converted into carbohydrates in the plant, which are then consumed, digested and released as methane by cows. After ten years in the atmosphere, the methane is broken down and converted into carbon dioxide. These are the same carbon molecules in the plant eaten by the animal, so the carbon removed from the atmosphere by the plant is returned to the atmosphere in a closed cycle.

“In short, it is “recycled” carbon, also known as biogenic carbon, which goes through a cycle and is very different from fossil carbon, which instead follows a one-way path from bottom to top in the air,” Professor Mitloehner points out: “If we keep the number of animals reared constant, the amount of methane produced by the cows and the amount of methane destroyed are in equilibrium. This means no new carbon is added to the atmosphere, and we have no additional warming”.

The #CarbonDioxide emitted 20 years ago by #car or #plane is still in the #atmosphere and will remain there for centuries. The #methane emitted by the digestion of #cattle is not. Click To Tweet

The methane from the farms is, therefore, considered a flow gas because it is destroyed when emitted. On the other hand, the carbon dioxide produced by fossil fuels is a reserve gas that accumulates in the atmosphere. In practice, the carbon dioxide emitted today is added to the carbon dioxide emitted yesterday, which was added to the carbon dioxide emitted the day before, and so on. Even the carbon dioxide you may have emitted twenty years ago when you travelled by car or plane is still in the atmosphere and will remain there for centuries. Methane emitted from cow digestion is not.

In short, livestock farming could achieve global cooling in the short term, which is essential if we keep global warming below 1.5 degrees Celsius. “What excites me most is that by reducing methane from cows, we are actively removing carbon from the atmosphere, almost as if we were storing atmospheric CO2 in the ground,” Mitloehner explains: “If you reduce the methane produced by cows, you are removing carbon from the atmosphere, and this induces global cooling”.

If you reduce the #methane produced by #cattle, you remove #carbon from the atmosphere and this induces #GlobalCooling. Click To Tweet

But can it be done? “It can be done, and it has been done,” the UC Davis expert says: “Here in California, for example, we have reduced methane by 25% by improving manure management. When you reduce methane, you create a powerful cooling effect, which means that cows are an important part of the solution to reducing our overall climate impact”.

Agriculture and livestock are the only human activities where carbon emissions and sequestration occur simultaneously. In Italy, new studies with updated metrics, which for the first time take into account the differences between methane and CO2, confirm that in the last ten years, farms have not affected the climate but have helped to cool the atmosphere with negative emissions of -49 million tonnes of CO2 equivalent.

Rethinking methane allows us to focus on both short- and long-term climate solutions while continuing to work to feed a growing population, experts say. But it will require farmers, regulators and researchers to work together, perhaps without the ideological blinkers that do more damage to the climate than the much-criticised cattle.

Journalist specialized in sustainability, climate change and environmental issues, he writes for various newspapers, magazines and websites. He worked in 2007 at the Center on Sustainable Consumption and Production, born from the collaboration between UNEP and Wuppertal Institut. Graduated in sociology, for years he has been focusing his work on the impacts of food production, starting from those related to animal husbandry and animal production. At the end of 2018 he has published the book “In difesa della carne” (“In defense of meat"), published by Lindau.