Ep. 345: Is all methane created equal?

Guest: Dr. Robert Howarth, Cornell University

The debate over agricultural methane is raging – cow burps and cow manure are in the eye of the storm.

Dr. Robert Howarth of Cornell University says, “Teasing the global warming potential of agricultural methane out of the global warming equation as less potent doesn’t matter because methane is methane.”

Haworth, however, acknowledges that “cow-produced methane is not the big culprit in global warming potential. It is by far and away the fossil fuel industry and in particular shale gas production that is of the greatest concern.” The reason Haworth says that shale gas-produced methane is a more potent greenhouse gas is because of the carbon isotope within it. Haworth says, “If you look at CO2 from fossil fuels and from most methane, the C-12 isotope is present, whereas in shale gas, the larger C-13 isotope is also present and it has different GHG impacts.” A claim Blair King says is difficult to support.

Haworth agrees with Dr. Myles Allen of Oxford University, who says, “The traditional way of accounting for methane emissions from cows overstates the impact of a steady herd by a factor of four. The errors distort cows' contributions – both good and bad – and, in doing so, give fossil fuel CO2 producers a free pass on their total GHG contribution."

Stuart McNish invited Dr. Robert Howarth of Cornell University to join him for a Conversation That Matters about digging deeper to understand the complex world of methane.