The methane myth: Why cows aren’t responsible for climate change

Cows have become the bad boys of climate change — but their place in the global warming debate is unfair, says air quality expert Frank Mitloehner.

From burping cows to grazing sheep, when it comes to global warming the finger of blame is invariably pointed at the livestock industry these days.

Animal agriculture is causing greenhouse gas (GHG) emissions to rise, say critics, and if we’re serious about tackling climate change then we need to cut red meat from our diets and switch cow’s milk for nut juices in our tea.

It’s an argument that’s gained a significant amount of traction, with more and more people adopting vegan diets in response to repeated reports — including from the United Nations — that livestock are a major contributor to the world’s environmental problems.

But while animal agriculture is by no means blameless in the global warming debate, it seems the industry’s impact on the environment is not as significant as critics suggest.

Air quality expert Frank Mitloehner, professor of animal science at UC Davis in California, says the real problem the livestock sector faces is convincing consumers and policy makers that animals aren’t the bad guys of the global warming challenge.

Critically, he says there should be an urgent rethinking of methane to acknowledge the true impact of livestock production on the planet — before the sector’s reputation is destroyed for good.

Overstated impact

“For those who say cows contribute the most GHG emissions, that’s simply not true,” Prof Mitloehner says.

Livestock’s impact has been hugely overstated, while the major culprit — the use of fossil fuels, particularly for transportation — has largely been allowed to slip under the radar.

The impact of ruminant livestock on temperatures is regularly overstated, says Prof Mitloehner, while transport’s impact receives much less focus.

The issue is partly down to the methods used to calculate livestock’s impact: The UN’s most significant report, Livestock’s Long Shadow, claimed livestock are responsible for 18% of GHG emissions, but the figure calculated emissions along the entire supply chain, from land use to processing and refrigeration in supermarkets.