Climate action: Should methane be measured the same as carbon dioxide?

A different metric should be used to measure methane emissions for climate change policy, according to a recent paper published by the Oxford Martin School, in the University of Oxford.

The paper, published last year, highlights that the current ‘one size fits all’ climate change policy does not take into account that there are two types of emissions that contribute to climate change – long-lived and short-lived pollutants.

Explaining the difference, Dr. Michelle Cain from the Oxford Martin Programme on Climate Pollutants, said: “Long-lived pollutants, like carbon dioxide, persist in the atmosphere, building up over centuries.

The CO2 created by burning coal in the 18th century is still affecting the climate today. Short-lived pollutants, like methane, disappear within a few years.

“Their effect on the climate is important – but very different from that of CO2: Yet current policies treat them all as ‘equivalent’.”

Prof. Myles Allen, who led the study, said: “We don’t actually need to give up eating meat to stabilise global temperatures.

“We just need to stop increasing our collective meat consumption. But we do need to give up dumping CO2 into the atmosphere.

“Every tonne of CO2 emitted is equivalent to a permanent increase in the methane emission rate. Climate policies could be designed to reflect this.”

Prof. Dave Frame, head of the Climate Change Research Institute at Victoria University of Wellington, added: “Under current policies, industries that produce methane are managed as though that methane has a permanently worsening effect on the climate.

But this is not the case. Implementing a policy that better reflects the actual impact of different pollutants on global temperatures would give agriculture a fair and reasonable way to manage their emissions and reduce their impact on the environment.

“Implementing a policy like this would show New Zealand to be leaders and innovators in climate change policy,” says Professor Allen.

“Implemented successfully, it could also completely stop New Zealand’s contribution to global warming.”

The work, which is a collaboration between researchers at Victoria University of Wellington, the Universities of Oxford and Reading, and the Centre for International Climate Research in Norway (CICERO), “shows a better way to think about how methane might fit into carbon budgets”, according to the Oxford Martin School.