Cows, which belch and fart methane, are a major source of greenhouse gas emissions. Credit: Charlie Litchfield/Associated Press file

This story was originally published by The Huffington Post and is reproduced here as part of the Climate Desk collaboration.

Most discussions about climate change focus on the challenge of reducing carbon dioxide emissions. And rightly so: Such pollution accounts for over two-thirds of the world’s greenhouse gas emissions.

But new research suggests these discussions ignore a disturbing trend of surging methane emissions – and addressing this issue head-on could help dramatically slow the warming of the planet.

According to a pair of papers that appeared Monday in the academic journals Earth System Science Data and Environmental Research Letters, emissions of methane over the past decade are approaching a “worst-case scenario.”

In the last two years especially, methane emissions have been climbing while carbon dioxide emissions have flattened.

While the trend is alarming, it also represents an opportunity, because of the ways in which methane differs from carbon dioxide, explained Rob Jackson, chairman of Stanford University’s Earth System Science Department and a co-author of both of Monday’s papers.

“Carbon dioxide lasts longer in the atmosphere, but methane acts more quickly,” Jackson told The Huffington Post. “So reducing methane is the quickest thing we can do to slow climate change.”

Scientists have yet to fully understand what is causing the recent surge in methane, but they are confident that the increase has more to do with biological sources – namely agriculture – than fossil fuel sources, Jackson said.

Agricultural practices yield methane in a number of ways.

Livestock release large amounts of methane into the atmosphere through their digestive processes. These animals’ manure is also a contributing factor, as methane is produced when manure is stored in holding tanks or lagoons. According to the analysis, rice paddies also produce methane when they are flooded.

Reducing these emissions could prove trickier than reducing emissions from fossil fuels, Jackson said, because the sources of the emissions are more widely dispersed among many smaller individual farms throughout the world.

“This is a global issue,” Jackson said. “There’s not any one country globally dominating methane emissions the way the U.S. and China dominate global carbon emissions, for instance.”

Still, the opportunities to cut methane from the atmosphere are numerous.

Strategies outlined in the analysis include promoting diets that are less meat-centric, tweaking livestock feed to make animals’ intestinal processes less methane-intensive and cultivating rice through processes that involve less flooding. Increased use of bio-digesters, which convert methane gas into an alternative energy source, could also have a big impact.

But it’s unclear whether the U.S. will take advantage of these opportunities anytime soon, given President-elect Donald Trump’s selection of Scott Pruitt – like Trump, a climate change denier – as the Environmental Protection Agency administrator, despite the widespread scientific consensus on global warming.

Trump also has promised to “cancel” the nation’s participation in the Paris climate agreement, which aims to reduce greenhouse gas emissions worldwide.

Despite the ominous political signs, Jackson is optimistic in the fight against emissions, particularly because data on the trend are consistently improving, so scientists can understand the phenomenon more thoroughly.

That knowledge is crucial, given the widespread benefits of mitigation, he said.

“When we reduce greenhouse gas emissions,” Jackson said, “we can reduce water use, improve air quality and save lives all at the same time.”

Creative Commons License

Republish our articles for free, online or in print, under a Creative Commons license.