Scientists find that belching cows could solve a key mystery about climate change and rising methane emissions

When it comes to climate change, we know where the most important warming agent – carbon dioxide – is coming from. Most of it is coming from the burning of fossil fuels, with some additional contributions from deforestation and other causes.

Now, new research published on Thursday in the journal Carbon Balance and Management by three scientists with the Joint Global Change Research Institute, a centre of the University of Maryland and the Pacific northwest National Laboratory, point the finger at agriculture once again – and more specifically, at cattle and other livestock.

“Just from livestock methane emissions, our revisions resulted in 11 per cent more methane in a recent year than what we were previously estimating,” said Julie Wolf, lead author of the study who completed the work while a postdoc at the institute, and now works at the Department of Agriculture. “It’s not the biggest contributor to the annual methane budget in the atmosphere, but it may be the biggest contributor to increases in the atmospheric budget over recent years.”

Cows and other ruminant animals release methane into the atmosphere as a result of a process that is called “enteric fermentation” – a technical term which basically refers to the digestive chemistry in the animals’ stomachs. As the EPA explains, the methane produced in this process “is exhaled or belched by the animal and accounts for most emissions from ruminants.”